Cluster Outbreak of Pneumocystis Pneumonia Among Kidney Transplant Patients Within a Single Center

Pneumocystis pneumonia (PCP), a life-threatening opportunistic infection occurring in immunocompromised hosts, developed in 10 patients in the past 35 years at our hospital. Among the 7 outpatients and 3 inpatients, 9 cases clustered within 7 months. The mean time was 32.1 +/- 27.5 months between transplantation and PCP diagnosis. The mortality rate was 33.3%. The patients developing PCP were older at transplantation (46.9 +/- 11.8 vs 34.0 +/- 11.1 years; P =.003) and had a longer pretransplantation dialysis period (146.3 +/- 120.0 vs 51.3 +/- 66.6 months; P < .0001). Multivariate analysis showed that age at transplantation and the use of mycophenolate mofetil (MMF) were risk factors for development of PCP. Despite prophylaxis with trimethoprim-sulfamethoxazole (TMP-SMX) during the first 3 to 6 months after transplantation, the time period that showed the highest incidence rate of PCP, the disease may occur at later intervals.