Folate Deficiency and Medication-Induced Severe Pancytopenia in a Bilateral Lung Transplantee.

Folate is a water-soluble vitamin that is essential to DNA synthesis and replication. Its deficiency is a leading cause of megaloblastic anemia, which is often asymptomatic but can present with nonspecific symptoms, such as fatigue and lightheadedness. Folate deficiency can rarely present with pancytopenia, which has been described in past case reports but even more scarcely in transplant recipients. We present a 74-year-old bilateral lung transplantee who presented with presyncope and was found to have severe pancytopenia with folate deficiency during the initial workup. Some medications, including mycophenolate mofetil, valganciclovir, and posaconazole were held. Peripheral blood smear showed blastoid cells, but follow-up imaging and flow cytometry negated any concern for a malignant process. Bone marrow biopsy showed an extremely hypocellular marrow with marked trilineage hypoplasia. He required blood product transfusions, but his admission was overall uneventful with no life-threatening sequelae. His blood counts improved with folate replacement and discontinuation of offending medications. He was discharged after nine days in stable condition. Two months later, he experienced a milder and self-limited recurrence of pancytopenia with normal folate and cobalamin levels.