The use of granulocyte colony-stimulating factor in the treatment of fever and neutropenia in a heart transplant patient.

We had the opportunity to study the clinical effects of granulocyte colony-stimulating factor in a heart transplant patient with a classic febrile neutropenic episode that was thought to be caused by immunosuppressive therapy. Administration of granulocyte colony-stimulating factor resulted in rapid recovery of his absolute neutrophil count, with resolution of fevers. Endomyocardial biopsy showed no pathologic evidence of worsened rejection. The use of hematopoietic cytokines after the organ allograft requires further study before it can be routinely advocated in this patient population.