Hematology Flashcards
7 cards from real Internal Medicine Exam practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Hematology flashcards as text
A 45-year-old woman presents with fatigue and pallor. Labs show Hgb 8.2 g/dL, MCV 72 fL, and low serum ferritin. What is the most likely diagnosis?
Answer: Iron deficiency anemia
Iron deficiency anemia classically presents with microcytic anemia (low MCV) and low serum ferritin, which is the most specific marker of depleted iron stores.
Which lab finding best distinguishes iron deficiency anemia from anemia of chronic disease?
Answer: Low serum ferritin
A low serum ferritin is highly specific for iron deficiency anemia; in anemia of chronic disease, ferritin is normal or elevated because it is an acute-phase reactant.
A 65-year-old man presents with Hgb 7.5 g/dL, MCV 110 fL, and hypersegmented neutrophils on peripheral smear. What is the most appropriate next step?
Answer: Serum B12 and folate levels
Macrocytic anemia with hypersegmented neutrophils strongly suggests megaloblastic anemia due to B12 or folate deficiency, which should be confirmed with serum levels.
Pernicious anemia results from which underlying mechanism?
Answer: Autoimmune destruction of parietal cells leading to intrinsic factor deficiency
Pernicious anemia is caused by autoimmune destruction of gastric parietal cells, leading to loss of intrinsic factor, which is required for terminal ileum absorption of vitamin B12.
A patient with sickle cell disease presents with an acute vaso-occlusive pain crisis. What is the MOST important initial management step?
Answer: IV fluids and adequate analgesia
Acute vaso-occlusive pain crisis is managed with IV hydration to improve blood flow and adequate analgesia (NSAIDs, opioids) to control pain.
Hereditary spherocytosis is caused by a defect in which cellular component?
Answer: Spectrin or ankyrin proteins in the RBC membrane
Hereditary spherocytosis results from mutations in RBC membrane proteins (spectrin, ankyrin, band 3), leading to loss of membrane surface area, spherocyte formation, and hemolysis in the spleen.
A patient with G6PD deficiency develops acute hemolytic anemia after starting primaquine. What is the underlying mechanism?
Answer: Oxidative stress causing Heinz body formation and hemolysis
G6PD deficiency impairs the pentose phosphate pathway, leaving RBCs unable to neutralize oxidative stress; oxidant drugs cause Heinz body formation and subsequent hemolysis.