Bone marrow nonneoplastic
Normal
Hematogones
Author: Dragos C. Luca, M.D.
Last author update: 1 August 2012
Last staff update: 26 July 2023 (update in progress)
Copyright: 2002-2023, PathologyOutlines.com, Inc.
PubMed Search: Bone marrow hematogones
Table of Contents
Definition / general | Clinical features | Case reports | Microscopic (histologic) description | Microscopic (histologic) images | Flow cytometry images | Positive stains | Negative stains | Molecular / cytogenetics description | Differential diagnosis | Additional referencesCite this page: Luca DC. Hematogones. PathologyOutlines.com website. https://www.pathologyoutlines.com/topic/bonemarrowhematogones.html. Accessed September 21st, 2023.
Definition / general
- Hematogones are lymphoid progenitor cells, usually < 1% of bone marrow cells
- May become hyperplastic ( > 5%), markedly hyperplastic ( > 25% - uncommon) or very numerous (70% - rare)
- Often found in young children as normal finding and may be most common lymphoid population in neonates (Biol Neonate 2004;86:247)
Clinical features
- Also associated with childhood cytopenias, neoplasms, viral infections, ITP (Egypt J Immunol 2005;12:9) and regenerative marrow after chemotherapy or bone marrow transplantation
- Occasionally encountered in adults with lymphoma, myelosuppressive therapy, chronic viral infections and autoimmune diseases (Am J Clin Pathol 1994;102:202)
- 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
- 3 month old boy with CMV and excessive hematogones (Leuk Res 2003;27:193)
- 7 year old girl with Shwachman-Diamond syndrome and CD5+ hematogones (Pediatr Dev Pathol 2001;4:505)
- Sisters with Shwachman-Diamond syndrome who died as neonates (Arch Pathol Lab Med 2000;124:1379)
Microscopic (histologic) description
- Hematogones: highly condensed chromatin, inconspicuous nuclei and scant cytoplasm; except for neonates, generally not evident in peripheral blood but are identifiable in pediatric bone marrow
- 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; not identifiable in normal bone marrow
- 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%; not identifiable in normal bone marrow
- 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%
Microscopic (histologic) images
AFIP images
Child with three large hematogone
cells in upper left that have sparse,
lightly basophilic cytoplasm
5 month old with neuroblastoma
and increased hematogones
evenly distributed
Hematogones have clumped
nuclear chromatin and
no distinct nucleoli
Images hosted on other servers:
Various images
Hematogones - left vs. ALL - right
Flow cytometry images
Images hosted on other servers:
Hematogones
Positive stains
- Commonly CD10+, CD38 (bright) and CD19+ by flow cytometry
- Heterogeneous expression of CD19, CD20, CD22, CD10, CD34 and TdT
- Also CD38, CD43 (Br J Haematol 2005;128:820)
- More CD20+ cells than CD34 / TdT+ cells (Am J Clin Pathol 2000;114:66); expression of CD20 and CD34 is mutually exclusive
- CD34 and TdT show a biphasic pattern
Negative stains
- Surface immunoglobulin
- No PAS+ globules
Molecular / cytogenetics description
- Normal karyotype
- Normal DNA content
- Negative clonality studies
Differential diagnosis
- ALL: homogeneous staining for various markers; maturation arrest, aberrant antigen expression and asynchronous antigen expression (Blood 2001;98:2498, Leuk Lymphoma 2004;45:277)
Additional references
