Class specific antibodies and fluorescent staining patterns in acute and chronic forms of schistosomiasis mansoni.

Sera from 40 patients with acute (10) and chronic (30) forms of schistosomiasis mansoni were studied in order to correlate class specific circulating antibodies with fluorescent patterns developed in sections of both worms and liver granulomata. At the acute stage of the infection, IgA antibodies were present, IgM titers were high (about 10 times those found in the chronic stage), and IgG, IgM, IgA, and IgE antibodies were shown by focal fluorescent staining of worms and granulomata. At the chronic stage, IgA antibodies were absent and IgG antibodies showed mostly a diffuse staining pattern in both kinds of sections. The relevance of these observations to diagnosis in clinical cases or epidemiological surveys is discussed.