Nocardiosis after bone marrow transplantation: a retrospective study.

To evaluate the spectrum of nocardiosis after marrow transplantation, we reviewed the medical records of 27 patients with nocardiosis who were treated at three centers, and we reviewed the findings of three cases reported in the literature. Nocardial involvement was defined as invasive nocardiosis (n = 25), colonization (n = 4), or contamination (n = 1). The median time to the diagnosis of nocardiosis after marrow transplantation was 210 days. Nocardia asteroides complex accounted for 96% of isolates. All 25 invasive infections occurred in allogeneic marrow recipients. Ten (40%) of 25 patients with invasive nocardiosis were receiving double-strength oral trimethoprimsulfamethoxazole twice weekly as prophylaxis for Pneumocystis carinii pneumonia. Treatment regimens for nocardiosis included sulfonamides; synergistic agents were also often added. The overall survival rate at 6 years was 34%; survival from the infection itself was 84%. Two of four nocardiosis-related deaths also involved other pathogens. The incidence of nocardiosis among allogeneic marrow recipients averaged 0.3% over 25 years. We conclude that nocardiosis is a rare infection that occurs later after marrow transplantation than other infections and that is marginally associated with increased mortality among long-term survivors of allogeneic marrow transplantation.