Step 2

Hematology 1

A 9-month-old infant girl presents to the emergency department with her concerned parent. She has seemed tired and fussier than normal over the past 3 months, and the mother thinks she is starting to develop abnormal physical features, most noticeably a large head. Her mother reports that her pediatrician ordered lab tests recently which showed a low red blood cell count. The infant was fine until 6 months old and was meeting all her developmental milestones. She is up to date with vaccinations. Family medical history is unremarkable. She is mildly tachypneic with normal oxygen saturation. The rest of her vital signs are within normal limits. On physical examination, the infant is noted to have slight pallor. She has frontal bossing, a depressed nasal bridge, and is short for her age. A complete blood count shows severe microcytic anemia. Further tests are ordered to confirm the suspected diagnosis.

Which of the following results would be expected regarding the most likely diagnosis?

  • A) Basophilic stippling on blood smear
  • B) Hemoglobin electrophoresis showing elevated alpha hemoglobin protein
  • C) Hypochromic red blood cells with erythroblasts on blood smear
  • D) Low serum ferritin
  • E) Mean corpuscular volume to red blood cell count ratio (MCV: RBC) < 13


Octavi Casals Farre


Dr. Ted O'Connell