Detection of Pneumocystis carinii in oropharyngeal washings by PCR-SHELA and nested PCR.

Oropharyngeal washings (Ophs) from 27 HIV infected patients (18 with P. carinii pneumonia, PCP, and 9 without PCP) were examined for P. carinii using morphological staining and DNA amplification with PCR-SHELA and nested PCR methods. The comparison of these techniques shows that 1. the amplification of P. carinii DNA is more sensitive than (and as specific as) morphological staining; 2. PCR-SHELA is less sensitive than (and as specific as) nested PCR.