Rapid microscopy technique for detection of Pneumocystis carinii in fresh clinical specimens.

A direct method for detection of Pneumocystis carinii was evaluated in 14 patients with impaired immune function (3 seropositive for HIV, 8 with AIDS and 3 with heart transplants) and signs and symptoms suggestive of Pneumocystis carinii pneumonia. Direct examination by phase-contrast and interference-contrast microscopy of fresh clinical specimens obtained by sputum induction, bronchoalveolar lavage or transbronchial lung biopsy was found to be a simple and rapid method for detection of Pneumocystis carinii, the sensitivity of the method being comparable to that of the classical toluidine blue O and Diff-Quik staining methods. These findings suggest that this direct microscopy technique could be considered for routine clinical application in patients with suspected Pneumocystis carinii pneumonia.