Infection with human immunodeficiency virus type 1 (HIV-1) and human T cell lymphotropic viruses among leprosy patients and contacts: correlation between HIV-1 cross-reactivity and antibodies to lipoarabinomannan.

To determine the association between leprosy and human retroviral infections, 57 leprosy patients, 39 leprosy contacts, and 500 pregnant women were investigated serologically for antibodies to human immunodeficiency virus type 1 (HIV) and human T cell lymphotropic virus (HTLV) types I and II. Antibodies to Mycobacterium leprae phenolic glycolipid I (PGL-I), and lipoarabinomannan (LAM) were also analyzed. A low prevalence of HIV-1 infection was observed among leprosy patients (3.5%), leprosy contacts (0), and pregnant women (3.6%). Antibodies to HTLV-I but not -II were found more often in leprosy patients (8.7%) and contacts (12.8%) than in pregnant women (0). Sera from leprosy patients and leprosy contacts were often false-positive for HIV-1 by ELISA and were indeterminate by Western blot. LAM IgM and PGL-I IgM antibodies in sera from leprosy patients yielded significant cross-reactivities with HIV-1 pol and gag proteins. These data suggest that mycobacterial cell wall antigens may share common epitopes with HIV. Caution should be exercised when interpreting HIV-1 ELISA and Western blot data from regions where leprosy or other mycobacterial diseases are endemic.