Primary Hematopoietic and Lymphoid Tissue ›› Bone Marrow ›› Myeloid ›› Erythroid (RBCs & Precursors) ›› Abnormal
Ring Sideroblast
›Microscopic Features:
- Size is variable depending on the stage of maturation
- nuclear to cytoplasmic ratio is variable depending on the stage of maturartion
- Round Nucleus
- Nucleoli are NOT visible
- Iron deposits are visualized with iron stain as blue granules (5 or more granules which encircles >1/3 of the nucleus)
›Normal % blood-PB, marrow-BM, lymphoid tissue-LN:
- PB: None
- BM: None
- LN: None
›May Resemble:
- Sideroblast is similar on iron stain but with less than 5 granules
›Differential Diagnoses:
Increased in:
Zinc toxicity induced copper deficiency
MDS (e.g. Refractory Anemia with Ring Sideroblast)
States of iron overload such as hemochromatosis (sometimes)
Zinc toxicity induced copper deficiency
MDS (e.g. Refractory Anemia with Ring Sideroblast)
States of iron overload such as hemochromatosis (sometimes)
›Classic Immunophenotype:
- CD45-
- CD117-
- CD235a (Glycophorin A) dim+
- CD71+
- Note: The immunoprofile can be variable and may show aberrancies
›Cartoon Image:
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for direct comparison
for direct comparison
›Misc:
Normally no more than 5 siderosomes (inclusions) are present per cell. Hence, ring sideoblast is an Abnormal finding.