Fever and Cytopenias After Heart Transplant
Clinical Vignette
A 62-year-old man with nonischemic cardiomyopathy undergoes orthotopic heart transplantation. Induction immunosuppression included rabbit antithymocyte globulin (ATG), followed by maintenance therapy with tacrolimus, mycophenolate mofetil, and low-dose prednisone.
He is discharged on valganciclovir for CMV prophylaxis and trimethoprim– sulfamethoxazole for Pneumocystis prophylaxis. His early post-transplant course is uncomplicated, and surveillance biopsy shows no rejection.
Five weeks after transplantation, he presents with fatigue and low-grade fever. Laboratory testing reveals hemoglobin of 7.1 g/dL (down from 10.8 g/dL at discharge), leukocyte count of 1.9 × 10⁹/L, and normal platelet count. Reticulocyte count is markedly reduced. Iron studies are normal.
Blood cultures, urine cultures, respiratory viral panel, CMV PCR, EBV PCR, and BK virus testing are negative. Computed tomography of the chest, abdomen, and pelvis shows no occult infection or lymphoproliferative disease.
Mycophenolate and valganciclovir are held due to leukopenia. He receives packed red blood cell transfusion and granulocyte colony-stimulating factor. Despite these measures, anemia and leukopenia persist, and he is readmitted two weeks later with recurrent fatigue.
A bone marrow biopsy is performed.
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References
Najar H, Goli K, Martinez Cantarin MP. Parvovirus B19 Infection in Kidney Transplant Recipients. Annals of Internal Medicine: Clinical Cases. 2025;4(5).