IgA testing for diagnosis of retroviral infections in the Caribbean.

In Guadeloupe, a Caribbean island with a high prevalence of HTLV-I infected subjects, the percentage of false positive results for HIV IgG is high, requiring additional time and expense for confirmatory tests. This article describes a simple way of overcoming this problem. First, all IgG and IgG immune complexes are removed by protein G treatment, and then IgA enzyme-linked immunosorbent assay (ELISA) and the Western blot test are performed with minor modification of commercially available kits.