Microcytic Anemia

Presentations

Herein we present 3 different patient presentations with a common diagnosis.

• Case 1: A 9-year-old boy with a normal diet presents for evaluation of fatigue. During review of systems, intermittent loose stools without hematochezia are reported. Screening laboratory values are obtained and reveal microcytic anemia (red blood cell [RBC] count, 4.6×10⁶/μL [4.6×10¹²/L]; hemoglobin level, 9.6 g/dL [96 g/L]; mean cell volume [MCV], 66 fL; and RBC distribution width [RDW], 14.7%) and a low serum iron level (<9 μg/dL [1.61 μmol/L]). He is given a presumptive diagnosis of iron deficiency and is started on replacement therapy. Four weeks later, repeated laboratory tests show only mild improvement (RBC count, 4.91×10⁶/μL [4.91×10¹²/L]; hemoglobin level, 10.3 g/dL [103 g/L]; MCV, 66 fL; RDW, 15.6%; ferritin level, 19 ng/mL). Additional laboratory values at this time reveal an elevated erythrocyte sedimentation rate (ESR) (32 mm/hr) and a decreased albumin level (2.6 g/dL [26 g/L]).

• Case 2: A 14-year-old boy with a regular diet is found to have microcytic anemia (RBC count, 4.5×10⁶/μL [4.5×10¹²/L]; hemoglobin level, 8.7 g/dL [87 g/L]; MCV, 60 fL; RDW, 15.6%) during evaluation for an acute febrile respiratory illness. At presentation he also reports a history of fatigue and 4 to 8 bowel movements per day with occasional episodes of hematochezia that predated his febrile illness. Further evaluation demonstrates occult blood in his stool on 3 separate samples, as well as a low albumin level (2.2 g/dL [22 g/L]) and an elevated ESR (55 mm/hr). …