Which of the following does not indicate megaloblastic anemia?
High-Yield Explanation
Ans. a. Increased reticulocyte count (Ref: Harrison 19/e p641, 18/e p865, 866; Wintrobes Clinical Hematology 12/e p1151, 1153; Robbins 9/e p645-648, 8/e p655)Increased reticulocyte count does not indicate megaloblastic anemia.Reticulocyte count is decreased due to destruction of fragile and abnormal megaloblastic erythroid precursors.Megaloblastic anemia is characterized by hypercellular bone marrow with abnormally large nucleated RBC. raised unconjugated bilirubin and mild splenomegaly.'Megaloblastic Anemia: Erythroid activity in the marrow is enhanced, although the megaloblastic cells die before they are released, accounting for the reduced reticulocyte count.'--Robbins 8/e p655)Characteristic Features of Megaloblastic AnemiaBone marrow: Hypercellular with a decreased myeloid/erythroid ratio and abundant stainable ironQ.Erythroid activity in the marrow is enhanced, although the megaloblastic cells die before they are release accounting for the reduced reticulocyte countRBC precursors: Abnormally largeQ and have nuclei that appear much less mature than would be expected from the development of the cytoplasm (nuclear-cytoplasmic asynchronyQ).Nuclear chromatin is more dispersed than expected and it condenses in a peculiar fenestrated patternQ that is very characteristic of megaloblastic erythropoesis.Raised unconjugated bilirubinQ : Mild reversible splenomegalyQ ( Wintrobes 12/e p1151)