ABSTRACT
BACKGROUND: Pneumocystis jirovecii is responsible for pneumonia in immunocompromised populations. Pneumocystis pneumonia has first been discovered as a common and life-threatening opportunistic infection in HIV-infected patients. OBJECTIVES: The aim of this study is to characterize the epidemiological aspects of Pneumocystis pneumonia and then to highlight an outbreak of this infection in a nephrology unit with molecular tools. PATIENTS/METHODS: A multilocus sequence typing method has been used to study the epidemiology of strains isolated during this episode. RESULTS: From January 2007 to April 2011, 39 cases of P. jirovecii pneumonia have been observed. In two thirds of cases, underlying diseases as transplantations, hematologic or solid malignancies, or immunodepressed treatment were the main risk factors and in one third of cases, there were HIV positive patients. This distribution is due to an outbreak of 13 cases in a nephrology unit, where the MLST resulted in two strains profiles regrouping each one 6 and 4 cases among the 10 available isolates. CONCLUSIONS: New categories of risk patients of Pneumocystis infection have emerged with severe clinical manifestations and mostly with a fatal outcome. The origin of the transmission is still unknown but a local transmission has been showed in our nephrology unit.
