Possible significance of antibodies to Legionella pneumophila in HIV-1 infected patients with acute respiratory illness.

: Eighty-six serum samples from 52 HIV-1 infected patients with complicating pneumonia illness were assayed for the presence of antibodies to Legionella pneumophila. In 25 of these patients Pneumocystic carinii has been previously diagnosed. Among all patients investigated only 4 had antibodies to L. pneumophila of significant titer of 128. In one patient L. pneumophila was demonstrated coexisting with P. carinii. Despite of a small proportion of patients with a significant titer of antibodies against L. pneumophila, the presence of this microorganism should be carefully investigated in AIDS patients with complicating pneumonia especially when the aetiological diagnosis is not defined; the reason is to improve the therapeutic treatment.