Bone marrow failure can be either inherited like in Fanconi's anemia, Dyskeratosis congenital and Diamond blackfan anemia or acquired as in aplastic anemia due to autoimmune causes, viral infections or drugs. Other diseases like paroxysmal nocturnal hemoglobinuria and myelodysplastic syndromes must be looked out for as they can present with aplastic anemia similar to bone marrow failure.
A complete blood count (CBC) will show low platelets, red cells and white blood cells (granulocytes and monocytes are severely decreased, although lymphocytes might be normal). This would generally give indication for diagnosing failure of bone marrow. A peripheral blood smear will show the morphology of the blood cells which will be helpful in differentiating conditions like MDS (Myelodysplastic syndromes ) from others. In addition tests like HAM test for paroxysmal nocturnal hemoglobinuria, hypersensitivity test with mitomycin C for fanconi anemia screening might be done.
But for definitive diagnosis of failure of bone marrow and differentiating from various leukemias, bone marrow biopsy is required. A hypoplastic bone marrow finding will confirm the diagnosis.
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