Pneumocystis carinii pneumonia is an opportunistic disease usually affecting immunocompromised hosts. Diagnosis is based on the microscopical detection of microrganism on BAL, an invasive sample which requires pt compliance for collection and skilled health care personnel for examination. In order to verify the possible diagnostic utility of noninvasive specimens collected in the upper respiratory tract we examined by the Internal Transcribed Spacers (ITSs) nested PCR, 39 oropharingeal samples (garglings) collected from 20 HIVAb positive pts and from 15 healthy controls.