Lymphocytic alveolitis bronchoalveolar lavage viral load, and outcome in human immunodeficiency virus infection

Lymphocytic alveolitis portends a poor prognosis in human immunodeficiency virus (HIV)-infected subjects. Because alveolar lymphocytes consist predomi nantly of HIV-specific CD8(+) cytotoxic T lymphocytes (CTL), they could rep resent an appropriate immune response to infected cells in the lung, and be a surrogate marker for a high pulmonary viral burden. We assessed long-ter m outcome in a cohort of asymptomatic HIV-infected subjects who underwent b ronchoscopy between 1990 and 1993 and had bronchoalveolar ravage fluid (BAL F) available for determination of viral load by reverse transcription-polym erase chain reaction. The ability to detect HIV in BALF increased with dise ase progression. Lymphocytic alveolitis, although present at all stages of HIV infection, was most pronounced in patients with middle stage disease. T he HIV viral load as measured by bronchoalveolar lavage correlated with the percentage of alveolar lymphocytes in patients with peripheral blood CD4() cell counts above 200/mu l. Including patients with CD4(+) cell counts <2 00/mu l weakened this correlation, possibly because of replacement of CD8() CTL by CD8(+) suppressor cells in advanced disease. Free virus in BALF wa s a stronger predictor of HIV disease progression than was lymphocytic alve olitis. These data suggest that lymphocytic alveolitis in HIV-infected subj ects occurs in response to viral antigens in the lung and that the poor pro gnosis associated with lymphocytic alveolitis reflects a high pulmonary vir al burden.