Bronchoalveolar lavage eosinophilia associated with Pneumocystis carinii pneumonitis in AIDS patients. Comparative study with non-AIDS patients.

Lower pulmonary tract cell populations collected by bronchoalveolar lavages (BAL) were evaluated in three groups of immunocompromised patients: HIV infected patients with Pneumocystis carinii (PC) pneumonitis (n = 22), or pneumonitis not related to PC (n = 29), and non-HIV-infected, immunocompromised patients with a PC pneumonitis (n = 18). In AIDS patients with PC pneumonitis, the cell populations were 59.3 +/- 4.5 percent alveolar macrophages (AM), 19.6 +/- 2.5 percent lymphocytes, 14.6 +/- 4.4 percent polymorphonuclear cells (PMN), and 10.3 +/- 3.6 percent eosinophils. In HIV-infected patients without PC pneumonitis, they were 76.5 +/- 3.3 percent AM, 13 +/- 2.1 percent lymphocytes, 9.2 +/- 0.3 percent PMN, and 0.6 +/- 0.2 percent eosinophils, and in non-HIV-infected, immunocompromised patients with PC pneumonitis, they were 43.9 +/- 5.7 percent AM, 30.2 +/- 4.3 percent lymphocytes, 20.4 +/- 4.7 percent PMN, and 0.9 +/- 0.4 percent eosinophils. The most striking finding was a marked BAL eosinophilia in AIDS patients with PC pneumonitis. The significance of this particular cellular pulmonary response to PC is not clear, and its consequences on the lung structures and/or PC require evaluation.