Histoplasmosis in Solid Organ Transplant Recipients: 10 Years of Experience at a Large Transplant Center in an Endemic Area

Background. Many clinical scenarios have been encountered by patients who developed histoplasmosis after receiving a solid organ transplant at a large transplant center in an endemic area. Methods. Cases of posttransplantation histoplasmosis were identified by use of multiple methods, including reviews of microbiology test results, transplant databases, and billing codes. Data were obtained retrospectively. Descriptive statistics were used. Results. During the 1997-2007 study period, 3436 patients received a solid organ transplant, and 38 patients were identified as having posttransplantation histoplasmosis. Of these 38 patients, 9 were excluded from our study because the diagnosis was solely clinical. Of the remaining 29 patients, 14 had posttransplantation histoplasmosis (incidence, 1 case per 1000 person-years); 14 showed histologic evidence of histoplasmosis in the recipient or donor tissue, which was encountered unexpectedly at the time of transplantation; and 1 had histoplasmosis before receiving the transplant. Of the 14 patients who developed histoplasmosis after transplantation, 5 were heart transplant recipients, 3 were lung transplant recipients, 3 were kidney transplant recipients, 1 was a liver transplant recipient, 1 was a pancreas transplant recipient, and 1 was a kidney-pancreas transplant recipient. The median time from transplantation to diagnosis was 17 months (interquartile range, 8.1-46 months), and the median time from onset of symptoms to diagnosis 3 weeks (interquartile range, 1.9-6.5 weeks). All recipients had disseminated disease. The most common treatment was amphotericin B and itraconazole. All were cured, or still on treatment, but symptom-free. Of the 14 patients who had an explanted organ or donor tissue that showed histologic evidence of histoplasmosis, 13 (93%) were lung transplant recipients, and 1 (7%) was a liver transplant recipient. None of these patients developed active histoplasmosis, but all received prophylactic treatment. Finally, 1 patient had histoplasmosis before transplantation; he was treated with itraconazole 3 months before and after transplantation, and he did well. Conclusions. In conclusion, posttransplantation histoplasmosis is rare (1 case per 1000 transplant-person-years; 95% confidence interval, 0.6-1.7), even in endemic areas. Prognosis is good but requires protracted therapy. Patients with latent infection did not develop posttransplantation histoplasmosis when prophylaxis was used.