Approach to Pancytopenia in a Deployed Service Member.

Background: Pancytopenia is a result of increased destruction or decreased production of bone marrow cells and has a broad differential. Pernicious anemia commonly presents as a macrocytic anemia and is typically autoimmune in nature and the result of vitamin B₁₂ deficiency. Pancytopenia is a rare presentation of this disorder especially in the setting of hemolysis. Testing in the deployed setting may be limited and/or challenging.

Case presentation: A 24-year-old female patient with a history of Hashimoto thyroiditis presented during an overseas deployment with a witnessed syncopal episode and was found to be pancytopenic with a mild transaminitis and laboratory tests demonstrating hemolysis. Though initially she was hypotensive, tachycardic, and febrile, her vitals improved after multiple transfusions, but she had persistent cytopenia with transfusion dependence, concerning for aplastic anemia or acute leukemia.

Conclusions: Testing for B₁₂ deficiency is crucial in symptomatic, patients with pancytopenic to either diagnose or exclude pernicious anemia and conserve resources by preventing costly workup and transfer/escalation of medical care, especially in the deployed setting. A predeployment screening in those with history of autoimmune disorders may be warranted.