Bone Marrow-nonneoplastic
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Last revised 6 February 2007
Copyright © 2001-2007 PathologyOutlines.com, Inc.
See also Bone Marrow tumors (future topic), Leukemia/myelodysplasia,
Lymphoma-B cell, Lymphoma-non B cell, Bone, Hematology (future topic)
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Table of contents
Primary references, images needed, embryonic development
Normal: general, basophils, eosinophils, erythroid maturation, hematogones, lymphocyte maturation, mast cells, megakaryocyte maturation, monocyte maturation, neutrophil maturation, osteoblasts, osteoclasts, plasma cells, age related changes
Bone marrow biopsy and aspirate smear: technique, sample report, routine stains
Alterations in cellularity: cellularity-general, amegakaryocytic thrombocytopenia, aplastic anemia, Diamond-Blackfan anemia, dyskeratosis congenita, Fanconi’s anemia, hypercellular, Schwachman-Diamond syndrome, TAR syndrome, pure red cell aplasia, treatment related
Benign changes: gelatinous transformation, Howell-Jolly bodies, iron, lymphoid aggregates, necrosis, persistent polyclonal lymphocytosis, plasmacytosis, polymorphous reactive lymphoid hyperplasia, systemic polyclonal B-immunoblastic proliferation
Anemias: megaloblastic
Infectious/inflammatory: Candida, CMV, Cryptococcus, Denge fever, granulomatous inflammation, histoplasmosis, HIV/AIDS, human granulocytic anaplasmosis, Leishmania, malaria, mycobacteria, parvovirus B19, Penicilliosis marneffei, Q fever, sarcoidosis, Whipple’s disease
Systemic disorders: Chediak-Higashi syndrome, cystinosis, Fabry’s disease, Gaucher’s disease, mucopolysaccharidosis type VII, Niemann-Pick disease, Pearson's syndrome, sea-blue histiocytosis syndrome, sickle cell
Other toxicity / deposition disorders: alcohol abuse, calcium oxalate, copper, podophyllin
Bone marrow transplantation: general
American Journal of Clinical Pathology (AJCP), January 1975 to December 2006
American Journal of Surgical Pathology (AJSP), March 1977 to December 2006
Archives of Pathology and Laboratory Medicine (Archives), January 1976 to December 2006
Human Pathology (Hum Path), March 1970 to December 2006
Journal of Clinical Pathology, January 1966 to December 2006
Modern Pathology (Mod Path), January 1988 to January 2007
Biomed Center, to 19 December 2006
Mills: Sternberg's Diagnostic Surgical Pathology (4th ed), 2004
Rosai: Rosai and Ackerman's Surgical Pathology (9th ed), 2004
Tumors of the Bone Marrow (AFIP Atlas of Tumor Pathology, Series 3, Vol 9)
AFIP images (not copyrighted) courtesy of www.PathologyResources.com
Websites with images: American Society of Hematology, PathoPic, PEIR digital library
Journal search terms: marrow and each disease entity listed
Please refer to these primary references for more detailed discussions and photographs
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Embryologic development of bone marrow
In embryo, hematopoiesis (other than lymphoid) occurs in yolk sac with formation of mesenchymal derived primitive erythroblasts
Aorta also contributes lymphomyeloid stem cells, as do embryonic liver and bone marrow (Development 2002;129:4147, Ann N Y Acad Sci 2005;1044:41)
At weeks 10 to 24, liver is primary hematopoietic organ with production of granulocytes and megakaryocytes in sinusoids
At months 4-5, bone marrow hematopoiesis begins
By birth, liver and spleen have minimal role in myelopoiesis, and bone marrow is major site of hematopoiesis
References: Int J Dev Biol 2005;49:243, Wikipedia (stem cells)
Normal bone marrow
3-6% of total body weight
Major organ for hematopoiesis at birth; also primary and secondary lymphoid organ
Hematopoiesis sites change from axial and radial skeleton in newborns to flat bones of central skeleton by mid-teens
Pluripotent stem cells develop into myeloid blasts (myeloblasts, monoblasts, erythroblasts and megakaryoblasts) or lymphoblasts
Cells are in storage pools for 5-7 days, then to blood, then to tissues
Hematopoietic stem cells: defined as cells with multilineage hematopoietic differentiation potential and sustained self-renewal activity; detected by their ability to regenerate long-term multilineage hematopoiesis in myeloablated recipients
Vasculature: nutrient (medullary) artery ramifies through marrow space to supply medullary cavity; its arterioles branch into capillaries that are continuous with thin walled sinusoids; sinusoidal walls have inner endothelial cells and outer adventitial reticular cells; outer adventitial reticular cells are phagocytic and can become lipocytes; also synthesize collagen, laminin, fibronectin and proteoglycans
Micro: arterioles, venules, capillaries, sinusoids, adipose tissue, connective tissue and hematopoietic cells; mitotically active cells are usually paratrabecular and perivascular
0.5% of all white blood cells
Progresses from myeloid stem cell to basophilic promyelocyte, to basophilic myelocyte, to basophilic metamyelocyte, to basophil
Similar to mast cells, but apparently generated by different CD34+ precursor cells in bone marrow
Leaves bone marrow as terminally differentiated granulocyte
Named because it stains with basic dyes
Basophils and mast cells are effecter cells in allergen/IgE-mediated immune responses; they induce type 1 immediate immune response in airways and elsewhere, causing bronchial asthma and other allergic diseases (Allergol Int 2006;55:105)
Also play a critical role in host defense against infection with helminthes (Allergol Int 2006;55:99)
Basophil activation test, using CD203c or CD63 as an activation marker, has become a reliable test for in vitro investigations of immediate allergy, complementing other in vitro tests (Clin Mol Allergy 2005;3:9)
Micro:
basophilic myeloblast: difficult to distinguish types of granulocyte blasts; large round cell with basophilic cytoplasm without granules; N/C ratio is 80%; dispersed chromatin with nucleolus
basophilic promyelocyte: intermediate in development between basophilic myeloblast and myelocyte; large round cell with a few undifferentiated cytoplasmic granules; slight chromatin clumping, nucleolus present
basophilic myelocyte: round/oval cell; minimal cytoplasm with slight basophilia, moderate cytoplasmic purple-black granules of varying size and shape; granules are usually larger than neutrophilic granules; N/C ratio is 50%; chromatin moderately condensed, no distinct nucleolus
basophilic metamyelocyte: oval cell with abundant pale cytoplasm with large and fairly uniform specific granules; N/C ratio is 40%; nucleus is small and indented with condensed chromatin, no nucleolus
basophil: smaller than other WBCs (10-15 microns); cytoplasm is homogenous pale-blue but often obscured by purple-blue granules (containing heparin and histamine); N/C is 20%; nucleus is often unsegmented or bilobed, chromatin is coarse
Positive stains: commonly used - CD9, CD25, CD38; also CD11a, CD11b, CD11c, CD13, CD15u, CD17, CD18, CD26, CD31, CD32, CD33, CD35, CD38, CD43, CD44, CD45, CD46, CD47, CD49d, CD50, CD55, CD58, CD59, CD63, CD68, CD71 (dim by flow cytometry), CD85A, CD85H, CD87, CD88, CD99, CD102, CD116, CD121b, CD123, Cd125, CD126, CDw128a, CD203c, HLA-DR (immature basophils, Allergy 2006;61:1063), histidine decarboxylase, 2D7 (J Clin Pathol 2006;59:396), basogranulin (AJCP 2006;125:273)
Positive stains: allergic subjects - CD32, CD122, CD124, CD130, CD154 (J Allergy Clin Immunol 2000;106:1190)
Variable: CD14, CD15, myeloperoxidase
Negative stains: CD2, CD3, CD7, CDw12, CD16, CD19, CD20, CD21, CD22, CD23, CD56, CD57, CD114, CD122, CD124, tryptase
References: Wikipedia, Cytometry 1999;35:249-flow cytometry markers, Allergy 1994;49:861-markers, Blood 1987;70:1872-markers
1-4% of all white blood cells
Progresses from myeloid stem cell to eosinophilic promyelocyte, to eosinophilic myelocyte, to eosinophilic metamyelocyte, to eosinophil
Named because granules stain deeply with eosin
Have a role in response to parasitic infections and allergic conditions
Degranulation is strictly controlled, which allows it to differentially release its contents in an ordered manner, which prevents tissue injury during migration (Semin Respir Crit Care Med 2006;27:117)
Produces: IL-2, IL-3, IL4, IL-5, IL-7, IL-13, IL-16, tumor necrosis factor-alpha, transforming growth factor-beta, RANTES, eosinophil cationic protein, eosinophil peroxidase, eosinophil derived neurotoxin, major basic protein and Charcot-Leyden crystal lysophospholipase
Micro:
eosinophilic promyelocyte: intermediate in development between a myeloblast and myelocyte; 15 microns in diameter with large nucleus and nucleolus; contains a few undifferentiated (primary, coreless) cytoplasmic granules in intensely basophilic cytoplasm
eosinophilic myelocyte: round/oval large cells with moderate cytoplasm containing prominent primary purple granules and secondary red-orange, refractile granules of similar size; N/C ratio is 50% with moderately condensed chromatin and indistinct nucleolus
eosinophilic metamyelocyte: round/oval cells with abundant cytoplasm containing large blue-orange granules; N/C ratio is 40%; nucleus is indented with moderately condensed chromatin and no nucleolus
eosinophil: 9-15 microns with coarsely granular cytoplasm containing refractile orange granules grouped around a single, horseshoe shaped nucleus with 2-3 lobes
Positive stains: CD9; also CD15, CD16, CD23, CD32, CD35, CD47R (weak), CD49d, CD50, CD52, CD62L, CD69, CD85A, CD85D, CD88, CD89, CD116, CDw125, CD183, myeloperoxidase, Sudan Black, PNL2
Negative stains: CD114, tryptase
References: Wikipedia, eMedicine
Erythroid maturation in bone marrow
Erythroid maturation (erythropoiesis) is characterized by increasing hemoglobin synthesis, decreasing cell size, decreasing cytoplasmic basophilia and extrusion of nucleus outside cell at orthochromatic stage of development
Progresses from myeloid stem cell to pronormoblast, to basophilic normoblast, to polychromatophilic normoblast, to orthochromatic normoblast (then extrusion of nucleus), to reticulocyte (young erythrocyte), to erythrocyte (red blood cell)
Early erythroid precursors cluster in islands randomly distributed throughout marrow but related to vascular structures
Erythroblast islands may be specialized niches where intercellular interconnections and cytokines regulate erythropoiesis (Curr Opin Hematol 2006;13:137)
Note: normoblast is also called erythroblast
Micro:
pronormoblast: 13-18 microns, round/ovoid with thin rim of basophilic cytoplasm, large spherical nucleus with fine chromatin and 1-2 nucleoli; usually perinuclear halo; N/C ratio is 90%
basophilic normoblast: 12-17 microns; increase in deeply basophilic cytoplasm compared to pronormoblast and slightly smaller nucleus with slight chromatin condensation; often perinuclear halo; no granules, no nucleolus; N/C ratio is 75%-85%
polychromatophilic normoblast: 12-15 microns; round/ovoid with abundant, dull gray to gray-green, variegated cytoplasm due to polyribosomes (basophilic) and hemoglobin (eosinophilic); round, condensed and basophilic nucleus has coarse granules that give it a checkboard (cart-wheel) appearance; perinuclear halo present; no nucleolus; N/C ratio is 60-80%
orthochromatophilic normoblast: 8-12 microns; round/ovoid cells with pink-orange uniformly staining cytoplasm, dark and opaque nucleus that may be pyknotic or in the process of being extruded, no nucleolus
reticulocyte: 7-10 microns; cannot identify without supravital stain (new methylene blue) that colors RNA deep blue and granular; must have at least 2 granules to classify as reticulocyte; cytoplasm is red to pale blue due to RNA, no nucleus is present; larger than mature erythrocyte and lacks central pallor
erythrocyte: 7-8 microns; round/ovoid biconcave disc with orange-red cytoplasm, no RNA, no nucleus
Positive stains: red blood cells - GLUT1, CD35, CD36 (early precursors), CD38, CD41, CD43, CD44, CD47, CD49d (erythrocyte precursors only), CD58, CD71 (precursors through reticulocytes), CD75, CD105 (erythrocyte precursors only), CD108, CD111, CD139 (weak), CD147, CD233, CD235a, CD235b, CD235ab, CD236, CD236R, CD238, CD239, CD240 CE, CD240 D, CD240 DCE, CD241
Negative stains: red blood cells - CD9, CD10, CD15, CD24, CD37, CD42a, CD45, CD46, CD47R, CD49d, CD53, CD57, CD71, CD81, CD82, CD114, CD226
References: Wikipedia (reticulocyte)
Hematogones are lymphoid progenitor cells
Often found in young children as normal finding, and may be most common lymphoid population in neonates (Biol Neonate 2004;86:247)
Also associated with childhood cytopenias, neoplasms, ITP (Egypt J Immunol 2005;12:9), and regenerative marrow after chemotherapy or bone marrow transplantation
May distort analysis of acute lymphoblastic leukemia in flow cytometry since markers are similar
Have been separated into three types (Neoplasma 2005;52:502)
Case reports: excessive hematogones in CMV+ neonate with immune thrombocytopenia (Leuk Res 2003;27:193), CD5+ hematogones in 5 year old girl with Shwachman-Diamond syndrome (Pediatr Dev Pathol 2001;4:505), sisters with Schwachman-Diamond syndrome who died as neonates (Archives 2000;124:1379)
Micro:
lymphoblast: resembles lymphoblasts in ALL; 10-20 microns (small/medium size), round/oval with sparse deeply basophilic cytoplasm without granules but may have vacuoles; indented nucleus with homogeneous fine, lacy and smudged chromatin; variable nucleoli
prolymphocyte: same size as lymphoblasts (10-20 microns) but more cytoplasm than lymphoblasts or mature lymphocytes, usually homogeneously blue cytoplasm; central round nucleus with single prominent nucleolus; coarser chromatin than lymphoblasts; N/C ratio is 75-85%
lymphocytes: 7-15 microns, round/ovoid but may have notches or indentations; variable light blue cytoplasm (often sparse); dense chromatin, usually no nucleolus; N/C ratio is 35-85%
Positive stains: commonly CD10+, CD38 (bright), CD19+ by flow cytometry; heterogeneous expression of CD19, CD20, CD22, CD10, CD34, TdT; also CD38, CD43 (Br J Haematol 2005;128:820); more CD20+ cells than CD34/TdT+ cells (AJCP 2000;114:66)
Negative staining: surface immunoglobulin
DD: ALL (staining is homogeneous for various markers, not heterogeneous; deviates from normal B cell maturation spectrum with maturation arrest, aberrant expression of myeloid antigens and asynchronous expression of B cell precursors, Blood 2001;98:2498, Leuk Lymphoma 2004;45:277)
References: AJCP 1994;102:202 (adults)
Lymphocyte maturation in bone marrow
Lymphocyte precursors originate in bone marrow
B cells complete most of their development within the bone marrow, but T cells are generated in the thymus from precursor cells that migrate from the bone marrow
B cell development in marrow is dependent on CD10+ stromal cells (J Pathol 2005;205:311), which form specific adhesive contacts with developing B lineage cells, and also provide growth factors (stem cell factor, IL-7, stromal cell derived factor 1)
Earliest stem cells are in subendosteum, adjacent to inner bone surface; with maturation, B lineage cells move towards central axis of marrow; final stages of development of immature B cells occur in peripheral lymphoid organs (spleen, lymph nodes)
Micro: diffusely scattered throughout interstitium; 10% of marrow cells in adults; aggregates often present
References: Immunobiology online textbook
Part of immune system
Similar to basophils, but generated by different CD34+ precursor cells in bone marrow
Mast cells leave bone marrow and circulate in immature form, and only mature at tissue site
Play a central role in allergic reactions through IgE receptor mediated responses
Stem cell factor is crucial for their development, proliferation and maturation (Immunol Res 2006;34:97)
Micro: rare in normal marrow; larger (up to 100%) than basophils with irregular elongated spindle shapes and cytoplasmic extensions; cytoplasm is packed with basophilic granules that may obscure nuclear margin; nucleus is round and single
Positive stains: Giemsa stain, Leder stain (chloroacetate esterase), methylene blue (granules stain purple), microphthalmia transcription factor, CD13 (immature and neoplastic mast cells), CD29, CD33, CD34, CD41, CD43, CD45, CD50, CD52, CD61, CD63, CD68, CD88 (J Allergy Clin Immunol 2005;115:1162), CD117, CD172a, CD203c
Negative stains: CD1-CD8, CD10-CD17, CD19-CD24, CD25 (non-neoplastic mast cells), CD38
References: Wikipedia, Blood 1989;73:1778
Megakaryocyte maturation in bone marrow
Progresses from myeloid stem cell to megakaryoblast to promegakaryocyte to megakaryocyte to proplatelets (released into circulation) to platelets (J Thromb Haemost 2003;1:1580, Front Biosci 2007;12:2050)
Maturation is characterized by an increase in size and lobulation of nuclei, and is controlled by thrombopoietin (J Clin Invest 2005;115:3339)
Megakaryocytes form demarcation membrane within cytosol, which leads to production of platelets
Micro:
megakaryoblast: variable size (7-35 microns); may be designated micromegakaryoblasts if less than 15 microns; round/ovoid cells with scanty blue agranular cytoplasm that often forms a rim around nucleus and may have a few small budding protrusions at periphery; nuclei are round/oval with coarse granular chromatin, one or more nucleoli
megakaryocyte: randomly disbursed throughout bone marrow; 50-150 microns (largest normal nucleated cell in marrow); micromegakaryocytes measure 15-30 microns; abundant light blue to pink cytoplasm with numerous purple-red or pink granules; nucleus has 8, 16 or 32 overlapping lobes; no nucleolus; megakaryocytes producing platelets may have demarcated granular clumps of platelets streaming from the margins
Positive stains: CD41, CD61; also CD9, CD31, CD34, CD36, CD42a, CD42b, CD42c, CD42d, CD43, CD49b, CD49f, CD51, CD62P, CD110, CD111, CD112, CD141, CD151, CD226 (Eur J Haematol 2005;74:228)
Negative stains: CD45, CD68
References: J Clin Invest 2005;115:3348, J Clin Invest 2005;115:3332
Monocyte maturation in bone marrow
Progresses from myeloid stem cell to monoblast to promonocyte to monocyte (bone marrow) to monocyte (peripheral blood) to macrophage (in tissues)
Difficult to identify monoblasts and promonocytes in normal bone marrow
Contain granules similar to those in neutrophils, but fewer and smaller
Monocytes are also precursors of dendritic cells
Micro:
monoblast - 12-20 microns, moderate basophilic cytoplasm without granules, often intense staining on periphery and with perinuclear zone, round/oval nuclei with fine chromatin and 1-4 nucleoli; nucleus may show indentations or folding
promonocyte - features intermediate between monoblasts and monocytes
monocyte - largest of leukocytes (12-20 microns); round with smooth margins or pseudopod-like cytoplasmic extensions; abundant agranular light-blue cytoplasm with fine pink azurophilic granules; may have vacuoles or phagocytized material; large bilobed, kidney shaped or U shaped nucleus with moderately clumped chromatin; no nucleolus; N/C ratio is 65-80%;
Positive stains: mainly CD14; also CD7, CD11a, CD11b, CD11c, CD11d, CD12, CD13, CD15 (variable), CD15u, CD17, CD18, CD23 (activated), CD29, CD30, CD32, CD33, CD36, CD37, CD38, CD39, CD40, CD43, CD44R, CD45, CD45RB, CD45RC, CD45RO, CD48, CD49a, CD49b, CD49d, CD49e, CD49f, CD51, CD52, CD54, CD61, CD62L, CD64, CD65, CD65s, CD68, CD83 (transient), CD84, CD85A, CD85B, CD85D, CD85E, CD85F, CD85I, CD85J, CD85K, CD85M, CD86, CD87, CD88, CD89, CD91, CD92, CD93, CD97, CD101, CD102, CD105 (activated), CD111, CD112, CD114, CD116, CD122, CD123 (plasmacytoid), CD126, CD127, CD128, CD132, CD137, CD139, CD141, CD148, CD156, CD157, CD163, CD165, CD166 (activated), CD171, CD180, CD210, CD226, CD227
Negative stains: CD24, CD56, CD57, CD60 (usually), CD231
Neutrophil maturation in bone marrow
Progresses from myeloid stem cell to myeloblast type I to myeloblast type II to promyelocyte to neutrophilic myelocyte to neutrophilic metamyelocyte to neutrophilic band to segmented neutrophil (polymorphonuclear neutrophil-PMN)
Maturation is characterized by decreasing N/C ratio and increasing granule production and nuclear segmentation
Immature forms are usually paratrabecular or perivascular; exceptions are after bone marrow transplantation, cytokine administration or chemotherapy
Primary granules: large, round, red-pink, electron dense; contain myeloperoxidase, elastase, lysozyme, cathepsin G, acid hydrolases; also called azurophilic (stains sky blue with azure stains used in the past); these granules are formed in promyelocytes (Blood 1979;53:179 , free full text)
Secondary (specific) granules: smaller, electron lucent (clear), cause characteristic cytoplasmic color in Wright stained preparations; contain lactoferrin and lysozyme; these granules are formed in myelocytes
Micro:
myeloblast: 15-20 microns, round/oval; usually scanty basophil cytoplasm with no perinuclear halo; may contain Auer rods (due to fusion of azurophilic granules) or delicate azurophilic granules; round/oval nuclei with occasional indentations or clefts; one or more nucleoli; finely reticulated chromatin; N/C ratio is 80-85%
type I myeloblast: no granules in cytoplasm
type II myeloblast: up to 15-20 delicate granules in cytoplasm
type III myeloblast: more than 15-20 cytoplasmic granules, but otherwise has features of a blast cell
promyelocyte: 10-20 microns; increased basophilic cytoplasm (compared to blasts) with primary coarse red-purple, azurophilic granules; large, round/oval nucleus with red-blue and fine to slightly condensed chromatin; 1-2 nucleoli; N/C ratio is 75-85%
myelocyte: 10-18 microns; round/oval with abundant pink cytoplasm with prominent red-purple azurophilic (primary) granules and numerous fine, lilac, specific (neutrophilic) secondary granules; round/oval to slightly indented nucleus with red-blue and slightly condensed chromatin; usually no nucleolus; N/C ratio is 50-65%
metamyelocyte: 10-16 microns; moderate pink or colorless cytoplasm with occasional red-purple azurophilic (primary) granules and variable fine, lilac, specific (neutrophilic) secondary granules; indented nucleus with light blue-purple and granular chromatin; no nucleolus; N/C ratio is 40-50%
band: 10-15 microns; abundant pink cytoplasm with many fine, lilac, neutrophilic (secondary) granules and possibly a few red-purple azurophilic (primary) granules; nucleus is indented to more than half the distance from the farthest nuclear margin; elongated and horseshoe-shaped nucleus; if lobulated, the bridge or isthmus between the lobes must be wide enough to have two distinct parallel dark margins with light nuclear chromatin between; has blue-purple and clumped granular chromatin; no nucleolus; N/C ratio is 33-40%
neutrophil: 10-15 microns; abundant pink cytoplasm with many fine, lilac, neutrophilic (specific or secondary) granules; lobulated (segmented) nucleus with 2-5 lobes, connected by a thin filament of chromatin; the filament is so narrow that there is no visible chromatin between the two sides; filaments may be difficult to visualize due to folding or twisting of nucleus; in other areas, the chromatin is dense with no nucleolus; N/C ratio is 33%
classify cell with folded nucleus as neutrophil if: (1) margins of two adjacent lobes are completely separated; (2) width of either of the two adjacent lobes markedly narrows or converges towards the junction of the lobes (making it possible for there to be a hidden filament), or (3) the nucleus is so extensively folded that one cannot determine if a filament is present
classify cell with folded nucleus as band if: (1) elongated band form crosses over itself without any evidence of constriction to a filament; (2) only the distal tip of the nucleus is slightly bent upon itself, and (3) the hidden area in the fold between two adjacent lobes is so small and the lobe width is so thick that it is unlikely that a thin filament is present
Positive stains: neutrophils (may also stain other precursors) - CD10, CD11b, CD11c, CD12, CD13, CD14 (weak-30%), CD15, CD15s, CD15u, CD16a, CD16b, CD17, CD18, CD24, CD29 (low), CD30, CD31, CD32, CD33 (low), CD35, CD37 (low), CD43, CD45RO, CD47, CD47R (weak), CD48 (weak), CD49e, CD62L, CD63 (weak), CD64, CD65s, CD66a, CD66b, CD66c, CD66d, CD66e, CD68, CD69, CD83, CD84, CD85F, CD85M, CD87, CD88, CD89, CD92, CD93, CD97, CD101, CD107a, CD107b (weak), CD114, CD116, CD128a, CD128b, CD132, CD139, CD141, CD148, CD156a, CD157, CD170
Negative stains: neutrophils - CD7, CD49d, CD52 (or weak), CD56, CD60, CD81, CD102, CD226
References: CAP proficiency testing handbook, Blood Cells Mol Dis 2002;28:260 (antigenic changes during maturation)
Along endosteal surface of bony trabeculae or along margins in marrow smears
Common in children; in adults associated with various diseases and healing biopsy sites
Bone forming cell that arises from marrow mesenchymal cells
Synthesize angiopoietin and osteopontin, which inhibit hematopoietic stem cell proliferation (Br J Haematol 2006;134:467, J Clin Invest 2006;116:1195)
When active, are plump and present on bone surface; eventually are encased within the collagen they produce and get flattened (and become osteocytes)
Synthesize and transport collagenous matrix, initiate and regulate mineralization, control removal of bone via osteoclasts, express Vitamin D receptors; activity is promoted by physical activity (Wolf’s law); express parathormone receptors (mediates the activation of osteoclasts)
Control osteoclast activity via parathyroid hormone (parathormone), PHRP (Parathyroid hormone related protein), IL-1, TNF alpha; digestion of bone by osteoclasts releases cytokines and growth factors for osteoblasts
Micro: large (25-50 microns), often oval, with abundant blue-gray cytoplasm and perinuclear hof; nucleus is round/ovoid with one or more nucleoli
Positive stains: alkaline phosphatase, estrogen receptor, parathyroid hormone, RANKL; also CD10, CD44, CD53, CD56, IL-12, IL-18, IFNgamma (Biosci Rep 2006;26:39); cells in culture express CD11b, CD13, CD16, CD20, CD23, CD25, CD34, CD44, CD54, CD80, CD86, HLA-DR (Cell Physiol Biochem 2002;12:359)
Negative stains: cells in culture are negative for CD3, CD14, CD15, CD45, CD68
EM: resemble fibroblasts due to well developed rough endoplasmic reticulum and Golgi
Along endosteal surface of bony trabeculae or along margins in marrow smears
Common in children; in adults associated with various diseases
Involved in bone resorption due primarily to remodeling and not calcium homeostasis
Derived from monocyte fusion
Activated by parathyroid hormone and by cytokines RANKL and macrophage colony-stimulating factor (Arthritis Res Ther 2006;8:201)
Osteoclasts use their ruffled borders (with villous extensions) to bind to matrix adhesion proteins, produce resorption pits/bays (shallow concavities) called Howship’s lacunae; plasma membrane forms a seal with bone; osteoclast acidifies extracellular area, which solubilizes the mineral and releases enzymes which dissolve the matrix
Micro: very large (up to 100 microns), multinucleated (2-12 nuclei) giant cells associated with bone surface; have abundant, blue-purple-pale pink cytoplasm containing many fine, red-purple granules; have multiple, relatively uniform but widely separate nuclei, each with one nucleolus and dense chromatin
Positive stains: CD13, CD31, CD51 (Histochemistry 1991;96:169), CD53, CD54, CD61, CD63, CD68, CD115, acid phosphatase, microphthalmia transcription factor, TRAP
EM: numerous mitochondria, rare lysosomes; ruffled edge in area of cell membrane is associated with bone resorption
References: Keio J Med 2003;52:1 (differentiation), Wikipedia
Usually less than 1% of marrow cells
Often perivascular and in particle crush specimens
Produces and secretes antibodies
Plasmablast: precursor to plasma cell
Micro: ovoid cells with abundant deep blue cytoplasm and perinuclear hof, eccentric nucleus with coarse chromatin and clockface (cartwheel) pattern; may have occasional binucleated cells; no nucleoli
Positive staining: CD38, CD138, CD19; also CD9, CD27, CD28, CD30 (some), CD31, CD32 (some), CD43, CD45, CD79a, CD79b, hc2, MNDA, PCA-1
Negative staining: CD20, CD21, CD22, CD24, CD37, CD40, CD56 (positive in myeloma, Am J Path 2002;160:1293), CD72 (Am J Hematol 1992;41:151)
EM: prominent Golgi and rough endoplasmic reticulum
Age related changes in bone marrow
Cellularity averages 79% at ages 0-9 years vs. 50% at ages 30-69 vs. 29% at ages 70-79
With aging, hematopoietic tissue is replaced by fat
Deeper medullary areas are typically more cellular than subcortical areas
B cell production declines with age (Curr Opin Immunol 2005;17:463), although the relative abundance of pro-B, pre-B, immature, naive, and mature B cells usually does not change appreciably between ages 24 and 88 years; occasional patients have exceptionally low numbers of lymphocyte precursors (Blood 2003;101:576)
Hypocellularity in elderly marrow may be due to increased apoptosis (Mech Ageing Dev 2000;117:57)
Bone marrow biopsy and aspirate smear
Trephine: A surgical instrument having circular, sawlike edges, used to cut out disks of bone, usually from the skull
Trephine biopsy: biopsy of a portion of bone containing marrow
Jamshidi-type biopsy needle: recommended, usually 11 gauge
Other needles: single use needle (Biomed Instrum Technol 2005;39:391), for neonates (Br J Haematol 1999;107:458)
Recommended to use separate needles for trephine biopsy and aspiration (J Clin Pathol 2007;60:212); can use same skin incision but sites a few millimeters apart
Bilateral biopsies useful if disease is likely focal (lymphoma or metastatic tumors, Cancer 2002;94:1522)
Sites: posterior superior iliac spine
Uses: to evaluate leukemia, lymphoma and lymphoproliferative disorders, myeloproliferative or myelodysplastic disorders, metastatic disease, aplastic anemia and other hematologic conditions, infectious and metabolic disorders; also to evaluate post-chemotherapy cellularity and post bone marrow transplant engraftment
Should be accompanied by aspirated marrow smears and particle crush preparations, and by touch imprints from trephine biopsy
Complications: adverse events in 0.8% (J Clin Pathol 2005;58:406); major complication is hemorrhage / hematoma (apply pressure bandage to biopsy site to prevent; obtain coagulation consultation if patient has bleeding disorder or is on anticoagulants)
Risk factors for hemorrhage are myeloproliferative disorder, aspirin, other putative platelet dysfunction and thrombocytopenia
Processing of trephine biopsy: (1) make imprints from trephine biopsy by gently touching glass slide to specimen; (2) possibly freeze part of trephine biopsy for molecular studies (J Clin Pathol 2006;59:1111), (3) fix tissue in formalin, B5 or Zenker’s; (4) decalcify for 45-60 minutes; (5) embed in paraffin; (6) section at 3-4 micron intervals, saving tissue for possible special stains and molecular studies
Some laboratories prefer plastic embedding, which may provide superior cytologic detail
Processing of aspirate: place some aspirate in EDTA, make smears at bedside with remainder; make smears from buffy coat (nucleated cell layer) and particles
Techniques: ultrasound decalcification may allow more successful FISH, PCR and RT-PCR (AJSP 2006;30:892)
Note: FISH can be performed on tissue imprints, cytopreps, or bone marrow aspirate smears (J Clin Pathol 2005;58:629)
Note: trephine biopsy may also reveal bone disorders not the reason for the biopsy
Steps
2. prepare and sterilize the site with iodine solution
3. anesthetize skin and bone with lidocaine
4. nick the skin with a blade to facilitate needle insertion
5. insert bone marrow aspiration needle
6. aspiration needle in place with trochar (white) partially withdrawn
7. syringe for aspirating bone marrow is in place
8. part of aspirate is put into EDTA tube to prevent clotting
9. part of aspirate is put on slide to pick particles
10. aspirate smear is made using another slide
11. biopsy needle is inserted at same site
12. feel the give of the needle as it enters the cortex
13. withdraw the trochar from the needle
14. after another centimeter push, rotate the needle to cut the end of the specimen
15. withdraw the needle with the specimen inside the needle
16. push the biopsy specimen from the narrow end to the hub end with the trochar
17. place the biopsy specimen in fixative (such as Zenker’s) for decalcification and processing
Micro: bone marrow biopsies are helpful to determine cellularity and presence of fibrosis; purple granular deposits that impair evaluation of touch preparations are due to cartilage in biopsy, and are more common in children (J Clin Pathol 2003;56:883)
References: Medical College of Virginia illustrated guide, eMedicine, J Clin Pathol 2006;59:903 (Hammersmith protocol), J Clin Pathol 2005;58:897 (epoxy resin embedding) , Wikipedia
Clinical history: indicate hematologic and other diagnoses, and indication for bone marrow
Peripheral blood smear:
List laboratory data (WBC, Hemoglobin, Hematocrit, MCV, Platelet count, RDW, other)
Give microscopic description (number, size, shape, other abnormalities) of red blood cells, white blood cells and platelets
Peripheral smear interpretation
Bone marrow biopsy and aspirate:
Biopsy or aspiration site
Cellularity (% and whether hyper-, normo- or hypocellular for age)
Presence or not of trilinear maturation
Adequacy of specimen
Indicate myeloid:erythroid ratio (M:E ratio), and whether normal, increased or decreased
Myeloid cells - normal or abnormal maturation; indicate if excess blasts, abnormal localization of immature precursors
Erythroid cell - normal or abnormal maturation
Provide differential of myeloid and erythroid elements, based on counting 200-500 cells in aspirate smear
Megakaryocytes - normal or abnormal numbers and morphology
Lymphocytes - lymphoid aggregates, hematogones, other abnormalities
Plasma cells - normal or increased, list abnormalities
Histiocytes - normal or increased, list hemophagocytosis or other abnormalities
Iron stores - quantitate (none, 1+, 2+, 3+ or 4+; indicate if normal, increased or decreased); indicate if ringed sideroblasts are present and how many
Fibrosis - present or not; normal or abnormal
Bone - list any abnormalities present
Cytogenetic findings
Molecular findings
Immunohistochemistry findings
Other - presence of metastatic tumor or not, other findings
Bone marrow interpretation / diagnosis - correlate with clinical history, cytogenetics, molecular or immunohistochemistry findings, peripheral blood smear
Mandatory features to report for accreditation purposes by the American College of Surgeons Committee on Cancer
Specimen type
Adequacy (adequate, limited, unsatisfactory)
Results of special stains or other studies, if performed
Results of cytogenetics, if performed
Diagnosis (WHO classification)
References: College of American Pathologist protocols, Archives 2006;130:1825 (synoptic reporting), how to examine aspirate smears, J Clin Pathol 2001;54:737 (trephine biopsy-Dr. Bain’s protocol), J Clin Pathol 2001;54:657 (aspirate smear-Dr. Bain’s protocol), AFIP Third Series-Bone Marrow-Appendix (specimen processing)
Note: reactivity varies by type of fixation
CD45/LCA - lymphocytes
Kappa and lambda light chains - to determine clonality or not of lymphocytes and plasma cells
Myeloperoxidase and lysozyme (for AML subtyping)
B cell markers CD20, CD79a and possibly Pax5
T cell marker CD3
TdT (for ALL)
Iron stains (Prussian blue) on aspirate smears and trephine biopsies (J Clin Pathol 2005;58:269)
0=absent, 1=trace; 2=present (sparse), 3=present (moderate), 4=abundant (abnormal)
Possibly reticulin stain or Masson trichrome stain
Also CD34 (blasts and blood vessels), Factor VIII (blood vessels), CD61 (megakaryocytes), CD68 (macrophages), Hemoglobin A (for AML-M6) and glycophorin (for erythroid cells)
Note: to assess iron stores, should examine at least 7-9 particles (J Clin Pathol 2004;57:1038); absence of staining iron is not diagnostic of iron deficiency anemia (Ann Hematol 2001;80:166)
Alterations in cellularity of bone marrow
Bone marrow cellularity-general
Best evaluated on biopsy sections or imprints; particle sections are next best choice; aspirate smears may be difficult to evaluate
Theoretically could use automated hematology analyzer or flow cytometry (Ann Clin Lab Sci 2004;34:307)
Iliac crest may not be representative if radiotherapy or other local insults
Varies from 80% (children) to 55% (age 30) to <50% (age 60+)
References: biopsy sections, imprints and aspirate smears are equally reliable - Am J Hematol 1986;22:381, Indian J Pathol Microbiol 1989;32:186
Amegakaryocytic thrombocytopenia and bone marrow
top
Also called Amega or CAMT (congenital amegakaryocytic thrombocytopenia)
Rare; autosomal recessive; usually diagnosed in early childhood
Presents with isolated nonimmune thrombocytopenia with decreased marrow megakaryocytes and high serum thrombopoietin levels
May have physical anomalies (Br J Haematol 2005;131:636)
Often evolves to aplastic anemia, myelodysplastic syndrome or leukemia
Diagnosis: biallelic mutations in c-mpl (thrombopoietin receptor) at 1p34 (Blood 2001;97:139)
Prognosis: missense mutations are associated with milder or delayed course vs. loss of function mutations (Hum Mutat 2006;27:296)
Case reports: due to anti-c-mpl antibody in woman with systemic sclerosis (Arthritis Rheum 2003;48:1647)
Treatment: stem cell transplantation
References: OMIM 604498
Aplastic anemia in bone marrow
Also called hypoplastic marrow
Rare acquired or congenital state of bone marrow failure with cytopenias and bone marrow hypocellularity
May be due to immune mediated destruction of marrow hematopoietic progenitor/stem cells, mediated via Th1 T cells (BMC Genomics 2006;7:263)
Children may acquire monosomy 7 (AJCP 2006;126:925)
Presence of substance P in B cells may predict progression to acute leukemia (J Clin Pathol 2006;59:935)
Acquired causes: idiopathic or due to drugs (carbamazapine and valproic acid, Epilepsia 2006;47:1232), chemicals, viruses, ionizing radiation; may be associated with thymoma, lupus (J Clin Rheumatol 2001;7:377); in children, cases are considered acquired only after excluding other causes; in adults, aplastic anemia is assumed to be acquired
Congenital causes (see below): dyskeratosis congenital, Fanconi’s anemia, Schwachman-Diamond syndrome, TAR syndrome
Laboratory: variable pancytopenia
Treatment: immunosuppressive therapy, bone marrow transplantation
Case reports: progressing to AML-M0 (J Clin Pathol 2005;58:670), 17 year old man with severe marrow aplasia, associated with trisomy 1q (Cancer Genet Cytogenet 2006;169:73)
Micro:
most severe - marrow space filled with adipose tissue with occasional lymphocytes, plasma cells, mast cells and hemosiderin-laden macrophages (reflecting increased iron stores from repeat transfusions); prominent sinuses and capillaries; no/rare hematopoietic cells
less severe - marrow space has increased adipose tissue and scattered small clusters of erythroblasts, granulocytes and megakaryocytes
rarely has polymorphous, non-clonal lymphoid aggregates; may also be associated with malignant thymoma
DD: newly diagnosed acute leukemia or myelodysplasia (CD34+ blasts and immature myeloperoxidase positive granulocytes are present, AJCP 1997;107:268, Leukemia 2006;20:458)
References: Hematology Am Soc Hematol Educ Program 2004:318, Wikipedia, OMIM 609135
Diamond-Blackfan anemia and bone marrow
Rare; pure red blood cell aplasia
90% are diagnosed in first year of life
May have short stature, abnormal thumbs
May progress to pancytopenia
Laboratory: macrocytic anemia with elevated fetal hemoglobin and increased red blood cell adenosine deaminase
Treatment: 15-25% undergo remission; also corticosteroids; if don’t respond, use red blood cell transfusions and iron chelation; also metoclopramide (Blood 2002;100:2687), stem cell transplantation
Molecular: mutations in RPS19 and RPS24 genes for small ribosomal protein in 25% and 2% (Am J Hum Genet 2006;79:1110)
References: OMIM 105650, Wikipedia
Dyskeratosis congenita and bone marrow
Also called Zinsser-Engman-Cole syndrome
Rare; 90% males; most patients are diagnosed as adults
Autosomal dominant cases linked to mutations in telomerase RNA gene (TERC) that impair telomerase function, leading to critically short telomeres
X linked cases linked to mutations in DKC1 gene encoding dyskerin, a small nucleolar ribonucleoprotein particle, important in ribosomal RNA processing and part of the telomerase complex (Int J Hematol 2005;82:184)
Severe variant is Hoyeraal-Hreidarsson syndrome, a multisystemic disorder with aplastic anemia, immunodeficiency, microcephaly, cerebellar hypoplasia and growth retardation
Causes progressive and ultimately fatal loss of hematopoietic renewal; also leukoplakia of mucous membranes (may become malignant), nail dystrophy and skin pigmentation
Case reports: with usual interstitial pneumonia (Mayo Clin Proc 2005;80:817, free full text)
Treatment: androgens, G-CSF, erythropoietin; bone marrow transplant
References: eMedicine, OMIM 305000 (X-linked), OMIM 127550 (autosomal dominant), OMIM 224230 (autosomal recessive), OMIM 300240 (Hoyeraal-Hreidarsson)
Fanconi’s anemia and bone marrow
Autosomal recessive
Most common inherited bone marrow failure syndrome; incidence at birth of 1 per 100-350K live births
10% diagnosed at age 16 years or older; rarely diagnosed in 40’s or 50’s
Progressive lethal anemia associated with brown skin pigmentation, hypoplastic bone marrow, renal hypoplasia, absent or hypoplastic thumbs or radii, short stature and other anomalies; some patients have milder phenotype
Associated with myelodysplastic syndrome, AML, hepatocellular adenoma
Presence of significant birth defects correlates with early onset hematologic disease / anemia
Note: Fanconi syndrome is a generalized dysfunction of proximal renal tubule transport with no primary glomerular involvement
Treatment: 50% improve with androgens; also G-CSF; stem cell transplantation
Median survival is 7 years
Molecular: chromosomal instability due to increased number of chromosomal breaks, gaps, rearrangements and endoreduplication; 12 mutated genes identified to date; proteins are involved in repair of DNA damage
References: OMIM 227650, Hematology Am Soc Hematol Educ Program 2005;96, Wikipedia, eMedicine
A finding, not a diagnosis
Usually reactive (infection, blood loss), but also other benign or malignant causes
Benign causes: megaloblastic anemia, sideroblastic anemia, compensatory hyperplasia after cell destruction
Erythroid hyperplasia: often due to hemolytic anemia
Megakaryocyte hyperplasia: often due to immune thrombocytopenia; megakaryocytes may have striking nuclear changes
Other causes include myelodysplasia or other ineffective hematopoiesis, leukemia, lymphoma, myeloproliferative disorders, metastases
Micro: increased hematopoiesis, reduced adipose tissue
Pure red blood cell aplasia in bone marrow
See also Diamond-Blackfan anemia (above)
Near absence of red blood cell precursors in the bone marrow with associated anemia and reticulocytopenia; normal amounts of megakaryocytes and white blood cell precursors
Usually is acute self limited
Causes: often idiopathic, B cell neoplasms or myelodysplastic syndrome (J Clin Pathol 2005;58:320); occasionally T cell large granulocytic lymphocytic leukemia, thymoma, autoimmune diseases, parvovirus B19 infection, various drugs, anti-erythropoietin antibodies (Eur J Clin Invest 2005;35 Suppl 3:95)
Case reports: 43 year old man with shortness of breath (J Clin Pathol 2005;58:1118), due to sickle cell disease, due to parvovirus
Treatment: steroids and immunosuppressants, antilymphocyte globulin, plasmapheresis, IV immunoglobulins
References: eMedicine
Shwachman-Diamond syndrome and bone marrow
Rare autosomal recessive childhood stem cell disorder with peripheral cytopenia (particularly neutropenia), ineffective hematopoiesis, and variable marrow cellularity; also pancreatic insufficiency with pancreatic fatty infiltration
Frequency develop aplastic anemia, myelodysplastic syndrome or acute myeloid leukemia
May be a myelodysplastic disorder from inception (Archives 2002;126:1157)
Laboratory: low serum isoamylase
Case reports: with successful bone marrow transplant (Eur J Pediatr 1999;158:995)
Micro-bone marrow: hypocellular; scattered mild dysplastic changes in all cell lines; may have prominent hematogones (Archives 2000;124:1379)
Positive stains: p53
Molecular: mutations in Shwachman Bodian Diamond syndrome gene in 90% (Blood 2004;104:3588)
References: Blood 1999;94:3048, Archives 2002;126:452, OMIM 260400, eMedicine, Wikipedia
Thombocytopenia absent radii (TAR) syndrome and bone marrow
Also called selective aplasia, hypoplasia of megakaryocytes with missing radii
Rare autosomal dominant disorder with bilateral absence of radii and thrombocytopenia
Lower limbs, GI, cardiovascular, and other systems may be involved
May have increased risk of acute leukemia (Eur J Haematol 2003;70:246)
Cause is unknown
Treatment: platelet transfusions as needed; rarely stem cell transplantation may be required
References: OMIM 27400, eMedicine
Treatment related changes in bone marrow
See also specific disorders
Vacuolated erythroblasts due to chloramphenicol, linezolid (Ann Pharmacother 2003;37:517)
Acute leukemia: initially hypocellular post-treatment with necrosis and proteinaceous debris, dilated sinuses, increased reticulin; then regeneration of marrow begins after 1-2 weeks
Benign changes of bone marrow
Gelatinous transformation of bone marrow
Also called serous transformation
Degenerative change of marrow, almost always in adults, 2/3 males
Associated with severe malnutrition (anorexia, alcoholism, AIDS), acute febrile illness, lymphoma, carcinoma, congestive heart failure, severe hypothyroidism (Archives 1987;111:375)
Bone marrow findings in anorexia correlate with amount of weight loss (AJCP 2002;118:582)
In HIV patients, gelatinous material is composed of glycosaminoglycans, which are detrimental to erythropoiesis (Archives 1992;116:504)
Associated with anemia (Indian J Pathol Microbiol 2005;48:1)
Micro: atrophy of fat cells and hematopoietic cells with accumulation of lightly staining eosinophilic serous fluid (mucopolysaccharides rich in hyaluronic acid) in interstitium
Positive stains: gelatinous material stains with Alcian Blue at pH 2.5 and 1.0
DD: biopsy site changes (granulation tissue and new bone formation with no adipose tissue and no hematopoietic cells; osteoblasts present along endosteal surfaces)
References: AJSP 2000;24:56, Hum Path 1978;9:685
Howell-Jolly bodies in bone marrow
Also called micronucleated reticulocytes
Red blood cell inclusions that are removed by a functional spleen
Micro: 1-2 micron red blood cell DNA inclusions, usually in peripheral blood not marrow
Positive stains: CD71 detects by flow cytometry (Mutat Res 2003;542:77),
Iron in plasma cells is associated with iron overload, dysgammaglobulinemia, AML, ALL, alcoholic liver disease, myeloma, iron overload, megaloblastic anemia (Acta Haematol 1994;92:126)
Case reports: 56 year old woman with cirrhosis (Archives 2002;126:873)
Lymphoid aggregates (benign) in bone marrow
See also persistent polyclonal lymphocytosis, plasmacytosis, polymorphous reactive lymphoid hyperplasia and systemic polyclonal B-immunoblastic proliferation
Frequent; incidence at autopsy of 26% to 62%
Incidence increases with age (Ann Clin Lab Sci 1989;19:345)
In younger patients, large aggregates are associated with immune disorders (AIDS, rheumatoid arthritis, immunotherapy with IL2 or rituximab)
In geriatric patients, significance is unknown
Up to 1/3 (all ages) may develop lymphoproliferative disorder (J Clin Pathol 1988;41:768)
Unusual to have marrow involvement by lymphoma in patient with no other manifestations of lymphoma
Micro: randomly distributed and usually NOT paratrabecular; small, well circumscribed, loosely structured, usually few in number; aggregates contain histiocytes, plasma cells, mast cells; lymphocytes are small and mature with round nuclei, condensed chromatin, no/small nucleoli; frequent vascular structures; germinal centers usually signify benign lesions;
post-rituximab aggregates are usually T cells
Positive stains: mixture of B and T cells within aggregate (CD20, CD3)
Negative stains: CD10, CD23
DD: SLL or other lymphoma (paratrabecular, irregular shape, infiltrate into adjacent marrow, homogeneous, tumor cells present in smears or imprints, usually no prominent vascularity, no germinal centers; clonal by PCR, Archives 2000;124:511)
References: J Clin Pathol 1999;52:294
Rare (2% of bone marrow biopsies)
Associated with malignancy in 90% (commonly leukemia / lymphoma, chemotherapy, radiation therapy); also anorexia, caisson disease (nitrogen bubbles, “bends”), drugs (St. John’s wort-Acta Medica (Hradec Kralove) 2005;48:91, imatinib for CML- Haematologica 2004;89:ECR32), infection, megaloblastic anemia, septic shock (Ann Fr Anesth Reanim 2004;23:501), sickle cell anemia (Am J Med Sci 2000;320:342), systemic lupus erythematosus (SLE)
Differs from avascular necrosis of cortical bone, although causes are similar
Often accompanied by severe and generalized bone pain; also anemia, leukopenia, thrombocytopenia, high serum LDH and alkaline phosphatase levels
Repeat biopsy may be needed for diagnosis (another site or after waiting for regeneration)
Treatment: varies with cause of necrosis; corticosteroids for CREST syndrome (Eur J Haematol 2005;74:75), often short survival (Indian J Pathol Microbiol 2000;43:47)
Gross: gelatinous aspirated specimen
Micro: early - nuclear pyknosis and karyorrhexis; late - all cell outlines gone, serous transformation of marrow
References: Cancer 2000;88:1769, Indian J Pathol Microbiol 2004;47:351, Am J Hematol 2002;70:300
Persistent polyclonal lymphocytosis and bone marrow
See also lymphoid aggregates, plasmacytosis, polymorphous reactive lymphoid hyperplasia and systemic polyclonal B-immunoblastic proliferation
Rare
Associated with young female smokers, hyposplenism, rheumatoid arthritis, Gaucher’s disease
Splenomegaly is common
Benign clinical course (Mod Path 2004;17:1087)
Associated with HLA-DR7 (Br J Haematol 1994;88:275) and elevated serum IgM (polyclonal)
Case reports: patient with low serum IgM
Micro-bone marrow: intravascular and interstitial B cell infiltrate resembling splenic marginal zone lymphoma; lymphocytes have abundant cytoplasm but are binucleated and mature; no germinal center or marginal zone patterns
Peripheral blood: small lymphocytes with one or two round/ovoid nuclei
Positive stains: CD19, CD20, bcl2, surface IgM
Negative stains: no light chain restriction
Molecular: t(14;18) is common involving bcl2 and IgH (oligo- or polyclonal), trisomy 3 and del(6) cytogenetics abnormalities; chromosomal instability present in 65% (Leuk Lymphoma 2004;45:1401)
DD: malignant lymphoproliferative disorders (clonal)
References: OMIM 606445
Plasmacytosis (benign) in bone marrow
See also lymphoid aggregates, persistent polyclonal lymphocytosis, polymorphous reactive lymphoid hyperplasia and systemic polyclonal B-immunoblastic proliferation
Common
Associated with lymphoid follicles, lipid granulomas and plasmacytic satellitosis (AJCP 1976;65:921)
Common (86%) in HIV+ patients (Indian J Pathol Microbiol 2005;48:7, Clin Immunol 2001;100:250)
Associated with mastocytosis (Sem Hop 1983;59:2119)
Case reports: patient with primary Sjogren’s syndrome and plasmacytosis mimicking myeloma (J Korean Med Sci 2005;20:506), due to pheochromocytoma (Endocr J 2005;52:193), due to methimazole induced aplastic anemia (Thyroid 2004;14:231)
Negative stains: CD56 (Am J Path 2002;160:1293, Histopathology 2004;44:375)
DD: myeloma / plasmacytoma (CD56+, clonal, immature and pleomorphic plasma cells), Castleman’s disease (Ann Pathol 1996;16:133), plasmacytic SLL/CLL
Polymorphous reactive lymphoid hyperplasia in bone marrow
See also lymphoid aggregates, persistent polyclonal lymphocytosis, plasmacytosis and systemic polyclonal B-immunoblastic proliferation
Associated with immune cytopenias, collagen vascular disease, AIDS (historically, Arch Anat Cytol Pathol 1991;39:137)
Micro: focal, poorly circumscribed, randomly distributed lymphoid aggregates; lymphocytes may be irregular and accompanied by plasma cells, immunoblasts, eosinophils, endothelial cells, mast cells, histiocytes and epithelioid histiocytes
DD: peripheral T cell lymphoma (clonal; rare in AIDS patients)
Systemic polyclonal B-immunoblastic proliferation and bone marrow
See also lymphoid aggregates, persistent polyclonal lymphocytosis, plasmacytosis and polymorphous reactive lymphoid hyperplasia
Reactive condition in patients with various immune disorders that simulates malignancy
Florid polyclonal proliferation of B-immunoblasts with polyclonal hypergammaglobulinemia
Involves blood, bone marrow, lymph nodes
May be related to EBV in middle-aged / elderly patients (Pathol Res Pract 2006;202:609) or Pseudomonas infections (AJCP 1992;98:222)
Micro: marrow shows infiltration by immunoblasts, plasma cells and intermediate forms
peripheral blood: leukocytosis with B cell immunoblasts (abundant, markedly basophilic cytoplasm, coarse chromatin and prominent nucleoli)
Positive stains: B cell markers
Negative stains: no light chain restriction
Anemias (more discussion in future Hematology chapter)
Megaloblastic anemia in bone marrow
Causes: Vitamin B12 or folate deficiency, bone marrow disorders (myeloma, myelodysplastic syndrome, aplastic anemia, acute leukemia), drug induced disorders of DNA synthesis (anticonvulsants, oral contraceptives, methotrexate and other chemotherapeutic drugs, sulfa drugs, AZT; table of drugs), hypothyroidism, liver disease
In West, 90% due to alcohol induced Vitamin B12 or folate deficiency
In Tunisia, due to Vitamin B12 deficiency caused by pernicious anemia (Haematologica 2006;91:990)
Vitamin B12 and folate are required coenzymes for thymidine synthesis; deficiency causes defective nuclear maturation
May be responsive only to thiamine (OMIM #249270)
Megaloblasts due to deranged cellular DNA synthesis, perhaps involving histones (Med Princ Pract 2005;14 Suppl 1:2)
Case reports: due to homocystinuria (Indian Pediatr 2004;41:941), due to intestinal parasites (Ann Hematol 2004;83:487)
Micro: enlarged erythroid precursors with finely stippled lacy chromatin
Positive stains-megaloblastic erythrocytes: non-specific esterase, Glycophorin A
References: Clin Med Res 2006;4:236, Hematology Am Soc Hematol Educ Program 2003:62 (cobalamin, folate, and homocysteine), eMedicine #1, #2 (pernicious anemia)
Inflammatory / infectious disorders of bone marrow
Candida infection may promote granulopoiesis (Stem Cells Dev 2004;13:39)
Case reports: isolated bone marrow infection in patient with fever, weight loss and fatigue (J Clin Pathol 2004;57:107)
Treatment: fluconazole, although resistance is emerging (J Antimicrob Chemother 2006;57:384)
Suppresses hematopoiesis (Blood 1990;75:1965)
Monocyte and granulocyte precursors are major site for latent CMV (Intervirology 1999;42:308)
Case reports: 57 year old woman with acute CMV infection causing transient clonal T cells in marrow (Am J Hematol 2001;66:64)
Micro: infected cells have intranuclear inclusions; occasional hemophagocytosis (Hum Pathol 1998;29:1074), granulomas (Postgrad Med J 1987;63:277), lymphoid aggregates (Rev Soc Bras Med Trop 2001;34: n4) or hematogones (Leuk Res 2003;27:193)
DD: pre-B ALL, T cell lymphoma
Usually associated with immunosuppression including HIV (Pathol Res Pract 2004;200:591)
Case reports: patient with nephrotic syndrome (Indian J Med Microbiol 2006;24:141), diagnosis based on bone marrow aspiration (J Pediatr Hematol Oncol 2004;26:526), auxotrophic pigmented variant (Med Mycol 2002;40:1)
Micro: thick capsule (Zhonghua Nei Ke Za Zhi 2005;44:902); granulomas are common (J Infect 2000;41:92, Malays J Pathol 2003;25:69); may have hemophagocytosis (J Infect 1998;36:118)
Transmitted by Aedes aegypti mosquito
Causes bone marrow suppression, DIC and thrombopathy (Baillieres Best Pract Res Clin Haematol 2000;13:261)
Case reports: causing AML in Chinese patient with HbH disease (Haematologica 2001;86:E17)
Micro: occasional extreme plasmacytosis (Archives 2003;127:1026), hemophagocytosis and dysplastic changes (Kaohsiung J Med Sci 2005;21:34)
References: Postgrad Med J 2004;80:588, MMWR 55(25);700
Granulomatous inflammation of bone marrow
Usually idiopathic, but may be due to amiodarone therapy (Am J Hematol 2004;75:110), tocainide therapy (South Med J 1994;87:839), hypersensitivity, sarcoidosis (10%, Haematologia (Budap) 2002;32:419), infections including fungi, infectious mononucleosis, Mycobacterium avium, Mycoplasma pneumoniae, Mycobacterium tuberculosis, Q fever (AJCP 1979;71:117), paracoccidioidomycosis (Histopathology 2006;48:377); also Hodgkin’s lymphoma and non-Hodgkin’s lymphoma with or without marrow involvement, which may coexist with other diseases (J Clin Pathol 2005;58:815)
Should perform stains for acid-fast bacilli and fungi in all cases; culture if AIDS or fever of unknown origin
Note: granulomas may be more difficult to identify on aspirate smears (Indian J Pathol Microbiol 2005;48:13), occasionally are sheets of histiocytes
Associated with fever and anemia
Case reports: granulomatous slack skin syndrome (Br J Haematol 2003;123:297), hemophagocytic lymphohistiocytosis (Pediatr Dermatol 2006;23:35), keratosis lichenoides chronica (J Dermatol 2007;34:41), Bartonella (J Med Microbiol 2007;56:133), M. tuberculosis (J Med Assoc Thai 2003;86:976), Toxoplasma (Rom J Intern Med 2003;41:323), typhoid fever (Intern Med 2004;43:436), Whipple’s disease (Hum Path 2004;35:522), after intravesicular BCG for bladder cancer (Eur J Intern Med 2005;16:301), with metastatic lobular breast carcinoma (J Clin Pathol 1997;50:166)
Micro: usually small, focal and non-necrotic; epithelioid histiocytes are often surrounded by well differentiated histiocytes; also lymphocytes and eosinophils; granulomas often paratrabecular
“doughnut” or ring granulomas - fibrin and inflammatory cells arranged around a central clear space; associated with Q fever (but not specific)
lipid granulomas - frequent; up to 1 micron, associated with sinusoids or lymphoid aggregates; macrophages contain fat vacuoles of varying size; also lymphocytes, plasma cells, eosinophils; giant cells in 5%
DD: malignant histiocytosis (AJCP 1980;74:180), Hodgkin’s lymphoma (Reed-Sternberg cells but usually few Langhan’s giant cells or epithelioid histiocytes)
Infection is common in US, particularly in Ohio and Mississippi River valleys; also Central and South America and Caribbean, but most infections are subclinical
Disseminated disease more common in immunosuppressed, including HIV; may be life threatening in these patients
Not always present in bone marrow, even with disseminated infections
Case reports: HIV+ woman with fever (Archives 2006;130:120), post bone marrow transplant (AJCP 1983;79:509)
Micro: numerous, small narrow base budding yeast cells (1-5 microns) within macrophages; capsule is oval with a colorless circle; may also be present within megakaryocytes (AJCP 1991;96:577); either discrete granulomas, lymphohistiocytic aggregates or diffuse macrophage infiltrates (AJCP 1990;93:367)
Positive stains: GMS, Giemsa, PAS; also Prussian-blue (J Clin Microbiol 1982;15:156)
References: eMedicine, Centers for Disease Control
Should have high index of suspicion of opportunistic infections (acid fast bacilli, Parvovirus B19, Pneumocystis, Histoplasma)
Some recommend GMS and AFB stains on all marrow specimens in AIDS patients; AFB particularly where TB is endemic (Indian J Pathol Microbiol 2005;48:7)
Increased incidence of lymphoma/other malignancies; also reduced iron stores (AJCP 2004;121:393)
Diagnostic yield for microorganisms is high for bone marrow biopsies (34%) and culture (27%), less (8%) for aspirate smears (J Infect 2006 Jul 25; [Epub ahead of print])
Case reports: 1996 case of HIV+ man who died with disseminated MAC infection, cutaneous Kaposi’s sarcoma and marrow bacillary angiomatosis (AIDS Patient Care STDS 2002;16:573)
Micro: usually hypercellular, but interstitium may be loosely structured and hypocellular; almost always increased plasma cells; often scattered macrophages, dysplastic hematopoietic cells (J Assoc Physicians India 2005;53:705) and marrow fibrosis (proportional to number of stained adventitial reticular cells, Archives 2005;129:1137); variable acid-fast bacilli without granulomas, polymorphous reactive lymphoid hyperplasia, proliferation of immunoblasts, naked megakaryocyte nuclei (nonspecific, Mod Path 1994;7:166), focal fibrinoid necrosis; rarely macrophages with PAS+ or GMS+ Pneumocystis carinii
Negative stains: no light chain restriction in lymphocytes/plasma cells (unless malignant)
DD: peripheral T cell lymphoma (rare, T cell receptor rearrangements), Hodgkin’s lymphoma
References: Arch Anat Cytol Pathol 1991;39:137
Human granulocytic anaplasmosis in bone marrow
Formally known as human granulocytic ehrlichiosis
Caused by Anaplasma phagocytophilum bacteria, which primarily infects mature granulocytes
Vector borne disease transmitted through bite of ixodes ticks
Bacteria is obligate intracellular pathogen that binds to P-selectin glycoprotein ligand-1 (PSGL-1/CD162); susceptibility also associated with expression of CD15s (J Clin Invest 1999;103:407)
First described in USA in 1994
Presents with fever, leukopenia, thrombocytopenia and elevated liver enzymes
Mortality up to 5%; particularly severe infections occur in elderly/immunocompromised
Case reports: patient with CML (J Clin Pathol 2004;57:499), pancreas transplant recipients (Transpl Infect Dis 2001;3:34)
Treatment: doxycycline
Micro: buffy coat examination may reveal intracytoplasmic inclusions (morulae) within neutrophils or monocytes
References: Centers for Disease Control, eMedicine
Visceral leishmaniasis is caused by the protozoan parasite Leishmania donovani and transmitted by the bite of infected sandfly Phlebotomus argentipes; is a parasitosis of mononuclear phagocytic system
Affects immunocompetent patients in endemic areas (South America, India, Northeast Africa, Mediterranean basin) and HIV+ or immunocompromised patients
Associated with fever, hepatosplenomegaly, hypergammaglobulinemia and pancytopenia
Diagnosis: Leishmania nested PCR (LnPCR) analysis of blood and bone marrow (J Clin Microbiol 2006;44:2343)
Case reports: with hemophagocytosis (Indian J Pediatr 2006;73:445), DNA present in donated blood (Am J Trop Med Hyg 2000;62:128)
Treatment: Amphotericin B
Micro: hypercellular with erythroid hyperplasia; often dysplastic changes in normoblasts; amastigotes in bone marrow smears and biopsies (Hum Path 2000;31:75); variable hemophagocytosis (Pediatrics 2000;106:E58)
EM: amastigotes within macrophages and occasionally neutrophils and granulocytes; also immature erythroblasts with giant lysosomes (J Clin Pathol 1987;40:267)
References: eMedicine, Wikipedia
Severe anemia may develop from Plasmodium falciparum malaria, even if no parasites are detected microscopically (Malar J 2005;4:56)
Pigmented erythroid and myeloid precursors (containing hemozoin pigment) are associated with the extent of abnormal erythroid development (Blood 2006;108:2569)
May cause hemophagocytic syndrome (Indian J Pathol Microbiol 2004;47:348)
Diagnosis: thick and thin films of peripheral blood; PCR on bone marrow (J Clin Microbiol 2006;44:2307)
Micro: often hypocellular marrows with erythroid hypoplasia and increased M/E ratio (Southeast Asian J Trop Med Public Health 2005;36:543); also hemozoin pigment in erythroid and myeloid precursors; abnormal erythroid precursors
References: eMedicine
Case reports: HIV+ with pseudo-Gaucher cells (J Clin Pathol 2005;58:1113), disseminated M. kansasii infection, HIV+ man with disseminated MAC, disseminated bCG infection leading to death (J Pediatr Hematol Oncol 2005;27:97)
Diagnosis: PCR on bone marrow for TB (Intern Med 2006;45:1297, Am J Trop Med Hyg 2006;75:960), culture
Micro: clusters of histiocytes with needle like inclusions; histiocytes resemble Gaucher’s cells; rarely hemophagocytosis in dialysis patients with TB (Int J Hematol 2004;79:334)
Positive stains: acid-fast
Parvovirus (Erythrovirus) B19 of bone marrow
Associated with HIV, but serology may be negative because patients cannot produce IgG antibodies (Hum Path 2000;31:161)
Affects bone marrow erythroid precursors, causing transient aplastic crisis in patients with hemolytic anemia or chronic anemia
Affects placenta and other tissues in fetuses, causing fetal hydrops or death
Also causes erythema infectiosum (Fifth’s disease), arthropathy (note: B19 DNA is common in rheumatic patients, but clinical significance is unclear, J Clin Virol 2005;33:71)
B19 DNA found in bone marrow of 2% of healthy individuals (J Clin Microbiol 2002;40:933)
Erythrovirus V9 causes similar pathology (J Clin Microbiol 1999;37:2483)
Chronic parvovirus infection: associated with immunodeficiency; erythroid hyperplasia, numerous inclusions, particularly in basophilic and polychromatic erythroblasts
Case reports: 50 year old man with chronic anemia, leukoerythroblastosis in newborn with B19 infection (Haematologica 2005;90:ECR38), with hereditary spherocytosis #1 (Postgrad Med J 2003;79:244), #2, in HIV+ patient receiving erythropoietin (Archives 2000;124:441), with malaria (Haematologica 2005;90:ECR41), in sickle cell patient #1 causing massive bone marrow necrosis (Haematologica 2006;91:ECR18), #2 (J Intern Med 1999;245:103, free full text), with systemic lupus erythematosus (Intern Med 2003;42:538)
Micro: marked erythroblast hypoplasia, immature giant erythroblasts; occasional erythroblasts may have intranuclear inclusions with surrounding rim of residual chromatin; rarely hemophagocytosis (Jpn J Infect Dis 2005;58:149)
Positive stains: Hemoglobin A, B19
DD: congenital dyserythropoietic anemia (J Pediatr Hematol Oncol 2004;26:133)
References: J Clin Microbiol 2006;44:604 (genotypes)
Penicillium marneffei in bone marrow
Major endemic mycosis of AIDS patients in Southeast Asia, China, Hong Kong and Taiwan
Almost always systemic with fever, weight loss and anemia; often nonproductive cough, skin rashes, hepatosplenomegaly and lymphadenopathy
Treatment: amphotericin B and itraconazole
Micro: normo- or hypercellular marrow; intracytoplasmic organisms similar to histoplasma, but also sausage cells with light blue cytoplasm and central cross walls (due to fission, not budding) and 1 or 2 purple-red small nuclei; normal or increased granulocyte and erythroid precursors; normal megakaryocytes
Positive stains: GMS, PAS
DD: Histoplasma (budding, intracellular only, no septum; often different epidemiology)
References: Chin Med J (Engl) 2002;115:1892, The University of Adelaide, Wikipedia, UCSF
Due to Coxiella burnetii, a rickettsiae usually not identifiable directly (AJSP 1985;9:752)
Acute primary Q fever is essentially benign, but may evolve into subacute Q fever endocarditis or a post-infectious fatigue syndrome
Organism persists in bone marrow for years (QJM 2005;98:7, Epidemiol Infect 2000;124:543)
Case reports: due to exposure to farm animals
Diagnosis: PCR or serology
Micro: suggestive finding is a fibrin-ring / doughnut granuloma defined as a small, non-necrotizing granuloma with ring-like structure composed of fibrinoid material, often with a central fat vacuole (Archives 1986;110:1017); rarely hemophagocytosis (Clin Infect Dis 1995;21:1029)
References: eMedicine #1, #2, Australian Department of Health, Centers for Disease Control, Clin Microbiol Rev 1999;12:518
Diagnosis of exclusion (perform GMS and acid-fast stains to rule out fungi and mycobacteria)
Case reports: isolated osseous disease (J Clin Rheumatol 2003;9:321), with hypercalcemia (Am J Med Sci 2005;330:147)
Micro: multiple non-caseating granulomas in 10% (Haematologia (Budap) 2002;32:419); occasional fibrinoid necrosis in active cases
References: eMedicine
Whipple’s disease of bone marrow
Chronic inflammatory disease due to Tropheryma whipplei bacteria
Usually affects small intestine
Diagnosis: PAS+ foamy macrophages, electron microscopy, PCR
Case report: 49 year old with bacteria detected by PCR in bone marrow (Hum Path 2004;35:522)
Micro: non-caseating granulomas, numerous foamy macrophages containing PAS+ diastase resistant bacteria
Positive stains: PAS+ diastase resistant bacterial inclusions within macrophages, CD68 and other macrophage markers
EM: bacilli within membrane bound vesicles
References: Clin Vaccine Immunol 2006;13:170, Clin Diagn Lab Immunol 2001;8:1, Wikipedia, eMedicine #1, #2
Systemic disorders affecting bone marrow, including lipid storage diseases
Chediak-Higashi syndrome and bone marrow
Rare autosomal recessive immunodeficiency disorder characterized by abnormal intracellular protein transport
Gene was characterized in 1996 as the LYST or CHS1 gene on 1q42-43 (OMIM 606897)
Mutations cause megagranules in promyelocytes and myeloblasts, which persist in mature forms, and are associated with neutropenia and recurrent pyogenic infections
Patients also have partial albinism (decreased hair and eye pigmentation), photophobia, nystagmus
Scalp hair analysis may also be useful for diagnosis (Clinics 2006;61:327)
Treatment: bone marrow transplantation for childhood onset cases is curative; disease is otherwise fatal
Micro: giant inclusion bodies in leukocyte precursor cells; also hemophagocytosis (Hematology Am Soc Hematol Educ Program 2005;82); bodies contain lysosomal enzymes
peripheral smear: giant granules in neutrophils, eosinophils and granulocytes
Positive stains: granules - myeloperoxidase
DD: AML (Pediatr Hematol Oncol 2004;21:199)
References: eMedicine, OMIM #214500
Nephrotic cystinosis is a rare autosomal disorder with defective cysteine transport out of lysosomes
Case reports: 23 year old man with hereditary cystinosis and crystals within bone marrow macrophages (Archives 2002;126:1135)
Treatment: cysteamine
Micro: crystals in marrow histiocytes and giant cells
EM: various abnormal findings (J Clin Pathol 2005;58:939)
References: eMedicine
Fabry’s disease and bone marrow
Also called alpha-galactosidase A deficiency, angiokeratoma corporis diffusum universale
X linked (Xq22.1) recessive lysosomal storage disease that affects 1 per 40,000
Due to deficiency in lysosomal alpha-galactosidase A, which catabolizes neutral glycosphingolipids
High penetrance in hemizygous males with symptoms at infancy or childhood
Heterozygous females have later age of presentation, more variable severity due to lyonization of X chromosome; may have normal leukocyte alpha-galactosidase A activity
Deficiency causes intracellular accumulation of galabiosylceramide (ceramide trihexoside) and digalactosyl ceramide within skin, renal glomeruli and tubular epithelium, blood vessels, corneal epithelium, myocardium and ganglion cells
Frequently misdiagnosed
Case reports: kidney disease
Treatment: recombinant human alpha-galactosidase A replacement therapy has only a modest effect, perhaps due to heterogeneous distribution (Mol Genet Metab 2006 Dec 21; [Epub ahead of print])
Micro: cells with small globular, lightly eosinophilic inclusions
Positive stains: PAS, oil red O, Sudan black, Luxol fast blue (all stain glycolipid and phospholipid-like material)
EM: characteristic single membrane bound intracellular inclusions (myelin-like figures, zebra bodies), that are 0.1 to 10 microns in diameter, round and lamellated with concentric electron dense layers, found in endothelial and smooth muscle cells, myocardium, fibroblasts and glomerular epithelium, urine sediment (Archives 1981;105:361)
DD (foam cell change): Gaucher’s disease, gangliosidoses, fucosidosis, mucopolysaccharidoses (all have different intracellular distribution and ultrastructural features of inclusions, can detect by laboratory assays), treatment with chloroquine, amiodarone or aminoglycosides (have similar myelin-like figures, Hum Path 2003;34:285)
References: Archives 1980;104:17
Gaucher’s disease and bone marrow
Autosomal recessive disease due to accumulation of glucocerebroside / glucosylceramine (a sphingolipid) in reticuloendothelial cells in liver, spleen and bone marrow, due to a defect in lysosomal beta-glucocerebrosidase
Increased risk of 14x for hematologic malignancies and 4x for other malignancies
Type I: chronic nonneuronopathic (adult) type; 99% of all cases; often completely asymptomatic; disease discovered incidentally; does not involve the nervous system; high prevalence among Ashkenazi Jews (1/12 are carriers); most patients have splenomegaly, anemia, thrombocytopenia and radiographic evidence of bone lesions
Type 2: acute neuronopathic type; fatal neurodegenerative disorder of infancy, similar to Tay-Sachs disease
Type 3: subacute neuronopathic (juvenile) type; slowly progressive neurologic disease with survival into adulthood
Confirm diagnosis with absence of glucocerebrosidase in peripheral blood monocytes
Treatment: glucocerebrosidase enzyme replacement therapy (imiglucerase), bone marrow transplantation
Case reports: Gaucher’s patient with splenic marginal zone lymphoma that progressed to diffuse large B cell lymphoma (Archives 2003;127:e242), type 1 with lytic bone lesions (Archives 2005;129:e148), 14 year old boy with splenomegaly (Archives 2000;124:1239), 7 year old boy with splenomegaly
Micro: small focal accumulations or diffuse replacement by ovoid histiocytes 20-90 microns, with abundant, finely fibrillar, pale blue-gray cytoplasm that is crinkled or wrinkled paper-like; small nucleus with coarse chromatin and indistinct nucleolus; increase in reticulin fibers; treated patients have decrease in size and number of Gaucher’s cells
smears: large 30-100 micron cell with fibrillary, pale-blue to eosinophilic cytoplasm, often with hemosiderin, one or more nuclei
Positive stains: iron, CD68 (AJCP 2004;122:359), PAS (may be weak); also TRAP, non-specific esterase, CD36 (AJCP 2004;122:359), but variable CD14 (Hum Path 1992;23:1410)
Negative stains: phospholipids stains, acid-fast stains; CD11b, CD40
DD: chronic myelogenous leukemia, type II congenital dyserythropoietic anemia and thalassemia have similar looking cells; also Whipple’s disease, histiocytic disorders, other lipid storage diseases, Mycobacteria infection (J Clin Pathol 2005;58:1113)
References: Wikipedia, OMIM #230800 (type I), OMIM #230900 (type II), OMIM 231000 (type III), eMedicine
Mucopolysaccharidosis Type VII disease in bone marrow
Very rare lysosomal storage disease due to deficiency of beta-glucuronidase, which degrades glycosaminoglycans
Causes progressive accumulation of glycosaminoglycans and subsequent lysosomal distension in multiple tissues
Micro: Alder-Reilly granules in neutrophils, monocytes, basophils and eosinophils; cytoplasmic inclusions surrounded by clear vacuoles in lymphocytes, plasma cells, osteoblasts, macrophages
Positive stains: granulocytes, monocytes, lymphocytes - acid phosphatase
References: AJCP 1982;78:544, eMedicine, OMIM 253220, Wikipedia
Niemann-Pick disease and bone marrow
Autosomal recessive sphingomyelin-cholesterol lipidoses
Types A/B: deficiency of lysosomal acid sphingomyelinase causes accumulation of sphingomyelin and other lipids in macrophages throughout the body
Treatment: bone marrow transplantation (variable improvement, J Inherit Metab Dis 2003;26:775)
Micro: clusters and individual foam cells up to 90 microns; cytoplasm has clear vacuoles of varying size, may be mulberry or soap-bubble like; nuclei are small and round with coarse chromatin
Positive stains: lipid stains
Negative stains: PAS
EM: intralysosomal myelin-like inclusions
DD: similar foam cells in hypercholesterolemia and Tangier’s disease; also disorders with massive cell destruction that overloads body’s capacity to digest lipids (thalassemia, sickle cell anemia, ITP, chronic renal failure)
References: eMedicine (types A/B), Wikipedia
Niemann-Pick type A
Acute neuronopathic form
Most common type
Occurs in infants
Presents with jaundice, hepatomegaly and profound brain damage
Usually death by age 2 years
No effective treatment
Molecular: types A and B due to mutations in SMPD1 gene
References: OMIM 257200
Niemann-Pick type B
Chronic form (visceral form) without nervous system involvement
Highest incidence in those of Turkish, Arabic and North African descent; uncommon in Ashkenazi Jews (Am J Hum Genet 2002;71:1413)
Onset of hepatosplenomegaly in pre-teen years
Good prognosis; may eventually require oxygen therapy due to lung involvement
Treatment: bone marrow transplantation, enzyme replacement
Micro: large macrophages with foamy cytoplasm; also sea-blue histiocytes (Ann Hematol 2001;80:620)
Molecular: types A and B due to mutations in SMPD1 gene
References: OMIM 607616
Niemann-Pick type C
Chronic neuronopathic form (NPC)
Rare (1 per 100K live births) disease of newborns
Autosomal recessive
May present in first few months of life with cholestatic jaundice or hepatosplenomegaly, or develop in adult years
Fatal in some; others live into adulthood
95% have mutations of NPC1 gene
Involves error of trafficking of cholesterol leading to accumulation of unesterified cholesterol, not sphingomyelin
Micro: macrophages with abnormal cholesterol storage (foam cells) in 60% (Arch Dis Child 2006;91:841); may also have sea-blue histiocytes
Molecular: due to mutations in NPC1 (OMIM 607623) or NPC2 (OMIM 601015) genes
References: OMIM 257220 (type C1), OMIM 607625 (type C2)
Niemann-Pick type D
Variable age of presentation
May have extensive brain damage
Usually moderate hepatosplenomegaly
Involves error of trafficking of cholesterol leading to accumulation of unesterified cholesterol, not sphingomyelin
Associated with family origin in Nova Scotia, Canada
Pearson's syndrome and bone marrow
Rare childhood disorder with refractory anemia, vacuolization of bone marrow cells, lactic acidosis and pancreas insufficiency
Those with a mild phenotype or supported through bone marrow failure may develop the encephalopathic features of Kearns-Sayre syndrome (ophthalmoplegia, retinal degeneration, ataxia and endocrine abnormalities)
Varied organ involvement due to heteroplasmy (mixture of more than one type of mitochondrial DNA; different mixtures cause variable effects), although most die by age 3
Intramitochondrial iron accumulation causes sideroblastic anemia, also reduction in cytochrome c oxidase activity (Eur J Haematol 2006;77:169)
Case report: 3 month old girl with anemia, neutropenia and lactic acidosis, with adrenal insufficiency (Minerva Pediatr 2005;57:143), fetal hydrops and spontaneous clinical remission (Chin Med J (Engl) 2003;116:1952), without marrow involvement (Arch Dis Child 1997;77:56), autopsy findings (Hum Path 1999;30:577)
Molecular: deletion mutations in mitochondrial DNA
References: eMedicine, OMIM 557000
Sea-blue histiocytosis (syndrome) and bone marrow
Clinical syndrome is associated with splenomegaly, mild thrombocytopenia and bone marrow involvement
Many reports using the term “syndrome” are actually reporting just a microscopic finding
Microscopic finding is associated with various hematologic and systemic disorders, including Niemann-Pick disease (Hum Path 1982;13:1115), as well as normal marrow, ceroid histiocytosis (Blood 1971;37:587), total parenteral nutrition (Leuk Lymphoma 1998;28:523)
Case reports: Niemann-Pick disease type B (Ann Hematol 2001;80:620)
Micro: histiocytes have cytoplasm filled with globules / granules of varying size containing blue or blue-green pigment (Romanowsky stain) or yellow-tan pigment (H&E)
Positive stains: CD68, Oil Red O, PAS, Sudan Black B
EM: myelin figures
DD: Gaucher’s disease, Whipple’s disease
References: OMIM 269600
Sickle cell disease and bone marrow
High sinusoidal blood flow in bone marrow predisposes it to blood stasis, causing regional hypoxia, acidosis, sickling and then thrombosis and infarction
Other complications are osteomyelitis and avascular necrosis
Case reports: with hemophagocytosis (Am J Hematol 2004;77:229), presenting with extensive bone marrow necrosis in Africa (Med Trop (Mars) 2004;64:179), eight month old with Salmonella osteomyelitis (Ned Tijdschr Geneeskd 2004;148:1695)
Micro: may have increased normoblasts and megaloblastic changes due to folate deficiency; increased perivascular fibrosis in small and medium sized vessels (Archives 2004;128:634); occasional aplastic crisis
Positive stains: CD1a, CD1b, CD1c in monocytes (Hum Immunol 2004;65:1370)
References: eMedicine #1, #2
Other toxicity / deposition disorders
Has variable hematological effects (Alcohol Clin Exp Res 2004;28:619)
May cause megaloblastic anemia due either to folate/B12 deficiency, or without these deficiencies
Cyanamide, used to prevent alcohol intake, may cause aplastic anemia (Eur J Clin Pharmacol 2005;61:467) or granulocytopenia (Intern Med 1997;36:640)
Alcohol abuse may also cause sideroblastic anemia (Postgrad Med 1992;92:147), severe osteoporosis (Calcif Tissue Int 2005;76:79) or TTP (Eur J Intern Med 2004;15:262)
Case reports: alcohol related megaloblastic anemia, 50 year old man with extensive alcohol and drug abuse, hypocellular marrow and increased blasts (Archives 2005;129:e35), megaloblastic anemia due to alcohol and mild folate antagonists (Dtsch Med Wochenschr 2005;130:2139)
Micro: may cause hypocellular marrow or reactive myeloblastosis with up to 34% blasts; vacuoles in proerythroblasts and other precursors; also ringed sideroblasts and iron granules in plasma cells
peripheral blood: leukopenia with vacuoles, hypersegmentation of neutrophils, thrombocytopenia; iron granules in plasma cells and other cells (J Clin Pathol 1982;35:172)
DD of cytoplasmic vacuoles: copper deficiency, lipid storage diseases, lipid granulomas, Mott cells, hematogones, monocytes
References: Acta Haematol 1987;78:252
Calcium oxalate granulomas of bone marrow
Associated with primary hyperoxaluria, small bowel syndrome and chronic renal failure (Clin Nephrol 2006;65:216)
Case reports: myelophthisis due to marrow replacement by calcium oxalate crystals and fibrous proliferation #1 (AJCP 1976;66:991); #2 (Blood 1998;91:4394)
Treatment: kidney and liver transplant for primary hyperoxaluria (Nephrology (Carlton) 2004;9:422)
Micro: radial pattern of yellow-white crystals within macrophages and multinucleated giant cells, doubly refractile in polarized light
Copper deficiency in bone marrow
Rare cause of sideroblastic anemia and neutropenia (Am J Hematol 2007 Jan 18; [Epub ahead of print])
Often due to excess zinc ingestion (CMAJ 2003;169:129); also zinc inborn errors of metabolism (J Pediatr Hematol Oncol 2005;27:477. Arch Neurol 2003;60:1303), total parenteral nutrition (Rinsho Ketsueki 1993;34:171)
Treatment: oral copper gluconate
Micro: resembles myelodysplasia or sideroblastic anemia; presence of cytoplasmic vacuoles is suggestive (Ann Clin Biochem 2005;42:227, AJCP 1992;97:665)
DD: myelodysplasia (Blood 2002;100:1493)
References: AJCP 2005;123:125
Podophyllin toxicity in bone marrow
Used as topical treatment of condyloma, although recommended to cease office based use due to toxicities (Sex Transm Infect 2001;77:409)
A mitotic spindle poison that binds microtubular proteins
Causes transient leukopenia and thrombocytopenia; can also cause coma and death
Micro: hypocellular marrow with cytoplasmic vacuoles in myeloid precursors and increased mitotic figures
References: AJCP 1982;77:478
Bone marrow transplantation
Bone marrow transplantation-general
Indications: (a) aplastic anemia, osteopetrosis or other primary/congenital bone marrow disease; (b) post-high dose chemotherapy for malignancy; (c) post transplant if blood counts do not recover as expected
Autologous transplantation: graft is patient’s own marrow, often after monoclonal antibodies to tumor or cell sorting regimen
Allogeneic transplantation: graft is from another individual after recipient myeloablative preparatory regimen of high dose chemotherapy, total body radiation or monoclonal antibodies
Nonmyeloablative allogeneic stem cell transplantation: in elderly or those with relatively indolent disease; myeloablative steps are reduced or eliminated as curative potential is largely due to graft versus tumor effect; similar outcome as traditional approach in patients more than 50 years old (Blood 2005;105:1810); examination of bone marrow morphology recommended post-transplant in additional to traditional molecular studies (Archives 2006;130:1479)
Peripheral blood transplant: uses CD34+ stem cells
Preparation: chemotherapy or total body irradiation to (a) immunosuppress patient to prevent rejection and (b) eradicate tumor cells
Complications: infection due to immunosuppression, graft rejection, graft versus host disease, recurrence of malignancy
Infection: less common due to antibiotics, growth factors
Graft rejection: rare with matched siblings; common with unrelated donors; characterized by decreasing marrow cellularity and progressive cytopenia
Decrease in a myeloid cell line may predict impending rejection, or be due to drugs or viruses
Erythroid hypoplasia may be due to parvovirus B19 infection in immunocompromised patients
Dyserythropoiesis and dysgranulopoiesis may reflect toxic effect of immunosuppressive drugs or antibiotics
Maturation arrest of granulocytes may occur due to various drugs
Granulocyte growth factors cause hyperplasia of immature forms and leukemoid peripheral blood reaction with Dohle bodies, abnormally segmented neutrophils and atypical granulation
Graft versus host disease: associated with increased lymphocytes, plasma cells and eosinophils
Micro (successful engraftment):
0-1 week - usually not biopsied; marked hypocellularity, hemorrhage, proteinaceous debris, scattered fat cells and macrophages
1-2 weeks - adipose tissue present
2-3 weeks - scattered islands of hematopoietic cells, often erythroid precursors initially, then promyelocytes and myelocytes
5-10 weeks - increasing erythroid precursors, granulocytes and megakaryocytes; megakaryocyte reconstitution may lag behind other cell lines
End of Bone Marrow-nonneoplastic chapter/outline