Amplification of Pneumocystis carinii DNA on specimens scraped from slides

A method for the detection of Pneumocystis carinii by polymerase chain reaction using specimens obtained by scraping bronchoalveolar lavage or tissue impression smears is described. The smears were scraped into water and then absorbed onto a glass-fiber filter. After fixing with methanol, the specimen on the filter was digested with proteinase K. The digestion mixture was then clarified, and a portion of the clarified supernatant was used as a template for the amplification of a portion of the mitochondrial rRNA gene of P. carinii. Using this method of sample preparation, we were able to amplify P. carinii DNA from both unstained and Giemsa stained smears.