Table of Contents
Definition / general | Laboratory | Treatment | Microscopic (histologic) description | Microscopic (histologic) images | Molecular / cytogenetics descriptionCite this page: Sangle N. MDS with single lineage dysplasia. PathologyOutlines.com website. https://www.pathologyoutlines.com/topic/myeloproliferativeRA.html. Accessed January 24th, 2021.
Definition / general
- Also called Refractory cytopenia with unilineage dysplasia
- Ineffective erythropoiesis with erythroid hyperplasia of marrow but low reticulocyte count and anemia
- Initially termed "refractory" because refractory to iron, folate and vitamin B12 supplements
- Diagnosis of exclusion; must eliminate other possible causes of anemia (folate / B12 deficiency, drugs, toxins, arsenic, congenital dyserythropoietic anemia)
- 90 - 95% of patients have a low or intermediate International prognostic scoring system score
- Occasionally evolves to more aggressive MDS or AML
Laboratory
- Anemia (Hb < 10g/dL), usually no other cytopenias
Treatment
- None or transfusion support
- Combination of all trans retinoic acid, calcitriol and androgens may be effective (Leuk Res 2006;30:935)
Microscopic (histologic) description
- Peripheral blood: anisocytosis (variation in size), poikilocytosis (variation in shape), normochromic oval macrocytes; usually no neutrophilic or platelet dysplasia; no / rare myeloblasts, monocytes are less than 1 billion/L
- Bone marrow: hypercellular or normocellular
- Erythroid: erythroid hyperplasia, may have mild to moderate dysplasia with megaloblastoid features; < 15% ringed sideroblasts
- Myeloid: myeloblasts < 5% (or call RAEB), no / slight dysplasia
- Megakaryocytes: no / slight dysplasia
- Patients with 2 - 4% blasts in peripheral blood and < 5% blasts in bone marrow should be classified as RAEB-1
Microscopic (histologic) images
Molecular / cytogenetics description
- No specific abnormality, 70% have normal karyotype (Atlas of Genetics and Cytogenetics)
- Refractory neutropenia and refractory thrombocytopenia are rare and caution needs to be exercised in making these diagnoses (these fall into the category of Refractory cytopenia with unilineage dysplasia)