To study non-invasively collected respiratory specimens such as oropharyngeal washing (OPW or gargle) paired with sensitive and specific molecular assays such as polymerase chain reaction (PCR) for the diagnosis of major HIV-associated opportunistic pneumonias such as tuberculosis (TB) and Pneumocystis pneumonia (PCP). The study demonstrated that PCR of sputum samples was highly sensitive (99%) and specific (88%) for detection of pulmonary TB and the assay performed well among HIV-infected patients and among patients with negative sputum smear results. PCR of OPW specimens was less sensitive (73%) but also detected a substantial proportion of tuberculosis cases. Collaborators: MU-UCSF Research Collaboration. Sponsored by: National Institute of Health (NIH)