A Febrile Woman With Unusual Blood Cell Counts
A 41-year-old woman presents to the emergency department with chest pain and dysphagia. Routine laboratory studies reveal profound neutropenia. She denies recent fever, chills, or weight loss.
The patient has a history of hepatitis B, hepatitis C, schizophrenia, and recent keratoplasty. Current medications include brimonidine eye drops, bacitracin and polymyxin B ophthalmic ointment, and famotidine. She lives alone, is unemployed, and smokes tobacco (4 or 5 cigarettes a day) and crack cocaine (2 or 3 times a week).
Two months earlier, the patient underwent a workup for agranulocytosis. A bone marrow examination showed normocellular bone marrow with trilineage hematopoiesis without blasts. She was given growth factor support, and her blood cell counts recovered by the time of discharge. Routine laboratory studies performed before her eye surgery 1 month later revealed a normal white blood cell (WBC) count and normal red blood cell (RBC) indices.
This petite woman is in no apparent distress. Heart rate is 107 beats per minute; blood pressure, 98/60 mm Hg; and temperature, 39.2°C (102.5°F). Examination of the oral mucosa reveals thrush and poor dentition. No cervical, axillary, inguinal, or supraclavicular lymphadenopathy is noted. Results of cardiovascular, respiratory, and abdominal examinations are normal.
WBC count is 2200/μL; absolute neutrophil count (ANC), 300/μL; hemoglobin level, 12.3 g/dL; and mean corpuscular volume, 83 fL. Platelet count is normal. Basic metabolic, hepatic, and renal function panels are all within normal limits. An HIV test is negative. Vitamin B12 and folate levels are normal. A peripheral blood smear reveals a normocytic RBC population, normal platelets, and a decreased WBC population. There are no blasts or abnormal white cells.