COMPARISON OF REAL TIME PCR AND MICROSCOPY FOR DETECTION OF PNEUMOCYSTIS CARINII IN BRONCHOALVEOLAR LAVAGE OF IMMUNOSUPPRESSED PATIENTS
Manal Ahmed El- Melegy
Department of Parasitology, Faculty of Medicine, Menoufiya University
In the present study we compared the real time PCR as a recent technique to four different microscopic staining techniques (Periodic acid Schiff (PAS), Giemsa. Masson trichrome and Toluidine blue) for detection of Pneumocystis carinii in bronchoalveolar lavage (BAL) of immunosuppressed patient was done. Forty BAL samples from immunocompromised patients suffering from long standing cough and other chest symptoms were examined. Out of forty BAL samples examined, Giemsa staining technique and Masson Trichrome stain equally detected two positive samples (5%) of the examined samples, while PAS staining technique detected only one positive (2.5%) of the examined samples. Toliudine blue technique was able to detect three positives (7.5%) of the examined samples. Real time PCR technique was the most sensitive technique as it could detect four positive samples (10%) with a sensitivity of (100%) compared to the most sensitive staining technique in this study (Toluidine blue) which was 75% Giemsa and Masson trichrome stains (50%). PAS stain was the least sensitive one (25%). These results prove that real time PCR is specific and sensitive technique for early and accurate diagnosis of P. carinii.