Frequency of Pneumocystis Jirovecii Colonization in Patients with Respiratory Failure Using Microscopic Methods

Background and Respiratory failures are common diseases among different populations. Pneumocystis jirovecii colonization causes respiratory failure in children and adults with AIDS and patients with predisposing factors of immunosuppression including malignancies, organ transplant, inherited immune deficiencies and immunosuppressive agents. The aim of this study was to evaluate the efficacy of three staining methods including Calcofluor White, Giemsa and Gomori Methenamine Silver in identification of Pneumosystis colonization using Bronchoalveolar lavage (BAL). The study population included 350 patients with respiratory failure who referred to Tehran Shariati Hospital and Sari Imam Khomeini Hospital during August 2013 to September 2014. Totally, 322 BAL samples, 26 induced sputa and 2 samples of sinus washing were evaluated for Pneumocystis jirovecii colonization after staining with the three specific staining methods. Data was then analyzed in SPSS V.16. The patients were 41.2% female and 58.8% male. The mean age of patients was 52 ± 4 years. Calcofluor White staining showed Pneumocystis jirovecii colonization in three patients (0.86%). In this study, Calcofluor White staining presented higher efficacy in identifying Pneumocystis jirovecii in BAL samples compared to other two microscopic procedures.