MLT GlobeHematology: RBC indices & anemias – page 4
138 Hematology MCQs on RBC indices & anemias with answers and explanations.
Hepcidin, the hormone that controls iron absorption and release, is produced mainly by the:
Hepcidin is made by hepatocytes. It blocks ferroportin, reducing iron absorption from the gut and iron release from macrophages.
Which pattern of red cell indices describes a microcytic hypochromic anemia?
Microcytic means a low MCV (small cells) and hypochromic means low hemoglobin per cell, shown by a low MCH (and often low MCHC). Iron deficiency is the classic example.
The common morphological classification of anemia into microcytic, normocytic and macrocytic types is based on which index?
The MCV (mean cell volume) gives average red cell size and is used to sort anemias into microcytic, normocytic and macrocytic groups.
A 29-year-old woman has Hb 7.8 g/dL, MCV 120 fL, WBC 2.3 × 10^9/L and platelets 85 × 10^9/L. The film shows oval macrocytes and hypersegmented neutrophils. Most likely diagnosis?
Oval macrocytes plus hypersegmented neutrophils are hallmarks of B12 or folate deficiency; ineffective hematopoiesis can cause pancytopenia. Aplastic anemia lacks hypersegmentation and marked macrocytosis.
What is the main role of the transferrin receptor on developing red cells?
Transferrin receptor 1 binds diferric transferrin and internalizes it by endocytosis, supplying iron for heme synthesis. Ferroportin exports iron from enterocytes; DMT1 takes it up from the lumen.
Both vitamin B12 and folate deficiency cause megaloblastic anemia. Which feature points to B12 deficiency specifically?
B12 is needed for myelin maintenance, so neurological damage occurs only in B12 deficiency. Glossitis, macrocytosis and hypersegmentation occur in both.
Which blood test best reflects total body iron stores when iron overload is suspected?
Ferritin rises with iron stores and, with transferrin saturation, is the main screen for overload. Serum iron fluctuates daily; TIBC reflects transferrin, not stores.
A patient with macrocytic anemia has low serum B12. Which test best confirms pernicious anemia as the cause?
Intrinsic factor antibodies are highly specific for pernicious anemia; low B12 alone does not identify the cause. Anti-parietal cell antibodies are sensitive but less specific.
A patient has anemia with spherocytes and raised bilirubin. Which test shows whether the hemolysis is antibody-mediated?
A positive DAT shows immunoglobulin or complement on red cells, confirming immune hemolysis. Osmotic fragility is raised in both hereditary and immune spherocytosis.
Coarse basophilic stippling of red cells is a typical film finding in which condition?
Stippling reflects aggregated ribosomes in cells with disturbed hemoglobin synthesis, as in thalassemia and lead poisoning. It is not a feature of the other conditions.
Elongated, pencil-shaped red cells on a film are a characteristic feature of which anemia?
Pencil (cigar) cells, a type of elliptocyte, are typical of iron deficiency, along with microcytic hypochromic cells. Sickle cells are crescent-shaped with pointed ends.
A patient with anemia of chronic kidney disease has a low reticulocyte count. What is the main reason?
Damaged kidneys make too little erythropoietin, so the marrow is not stimulated. Deficiencies of iron, B12 or folate and marrow disease also blunt the reticulocyte response.
At about what age does anemia usually become evident in β-thalassemia major?
Before birth, HbF (α2γ2) needs no β chains. As γ-chain production falls after birth, the β-chain defect causes severe anemia in the first months of life.
By WHO criteria, what hemoglobin level defines severe anemia in a non-pregnant adult?
WHO grades anemia in non-pregnant adults as mild, moderate (8.0–10.9 g/dL) and severe (below 8.0 g/dL). The cut-offs apply to any cause, including iron deficiency.
Extramedullary hematopoiesis in the liver and spleen is LEAST expected in which situation?
Extramedullary hematopoiesis occurs physiologically in the fetus and when marrow is overwhelmed or fibrosed. In secondary polycythemia the normal marrow simply responds to erythropoietin.
Which gastric finding is expected in pernicious anemia?
Autoimmune destruction of parietal cells abolishes acid and intrinsic factor secretion. Achlorhydria drives G-cell hyperplasia, so gastrin is high; anti-intrinsic factor antibodies occur in about half of patients.
Raised serum iron with reduced TIBC and high transferrin saturation fits best with:
In sideroblastic anemia iron cannot be used for heme, so iron accumulates and TIBC falls. Iron deficiency raises TIBC; chronic inflammation lowers both iron and TIBC.
Which complication is NOT typically associated with sickle cell anemia?
Sickling causes infarction of the renal medulla, bone infarcts prone to Salmonella infection and chronic anemia with cardiac strain. Pancreatitis is not a characteristic complication.
Ferrochelatase inserts iron into protoporphyrin IX in which form?
Heme contains ferrous iron; iron released from transferrin in the ferric state is reduced before ferrochelatase incorporates it in the mitochondria. Ferric heme (methemoglobin) cannot carry oxygen.
Low serum iron with low TIBC and normal or raised ferritin suggests:
Hepcidin in inflammation traps iron in stores, lowering serum iron while ferritin stays normal or high, and transferrin (TIBC) falls. True iron deficiency raises TIBC.