A laboratory comparison of immunofluorescent assay and polymerase chain reaction (PCR) methods for detection of pneumocystis jirovecii in bronchoalveolar lavage.

ABSTRACT

Pneumocystis jirovecii is one of the most common causative agents of Pneumocystis pneumonia in immunocompromised patients. Because of problems in the laboratory diagnosis, the majority of cases are diagnosed by medical response. In this study, an evaluation of the detection techniques for Pneumocystis jirovecii in bronchoalveolar lavage (BAL) was performed. Immunofluorescent assay (IFA), simple-polymerase chain reaction (simple PCR) and nested-polymerase chain reaction (nested PCR) methods were compared. This study was carried on sixty samples of BAL, from patients sent to the Department of Parasitology, Faculty of Medicine Siriraj Hospital, Mahidol University, were included in the study. Twenty-three of the samples (38.3%) were found to be positive by IFA. Twenty-five of them (41.6%) were found to be positive by PCR; and 56 of them (93.3%) were found to be positive by nested PCR. As a result, the simple and nested PCR, which are rapid and reliable diagnostic tests, can be used for the screening detection of this organism.