Markers of human immunodeficiency virus infection in pediatric bronchoalveolar lavage samples.

Pulmonary cells and fluid obtained by bronchoalveolar lavage (BAL) from 19 pediatric acquired immunodeficiency syndrome (AIDS) patients with pneumonia were examined for markers of human immunodeficiency virus (HIV-1) infection. The HIV-1 DNA was detected in BAL cells by polymerase chain reaction (PCR) in 14 of 15 patients (93.3 percent). Immunostaining of cytocentrifuged cell preparations of six specimens revealed that HIV-1 antigen was associated with from five percent to 95 percent of the alveolar macrophages. Analysis of the 22 cell-free BAL fluids by enzyme immunoassay (EIA) showed that samples from three patients (15.8 percent) contained HIV-1 p24 antigen. One sample, with a dilution factor of 15.1 relative to serum, contained a markedly elevated antigen concentration (106 pg per ml) compared to the serum concentration (41.6 pg per ml). Antibodies to HIV-1 were present in the BAL fluids of six patients (31.6 percent) at levels detectable by EIA. By Western blot analysis, three samples yielded more intense gp120 bands compared to bands observed with matched serum samples. Our results suggest that HIV-1 and antibodies to this virus are frequently present in the lungs of children with AIDS and that the serum antigen and antibody profile of some patients does not reflect local pulmonary levels.