Diagnostic tests for amoebic liver abscess: comparison of enzyme-linked immunosorbent assay (ELISA) and counterimmunoelectrophoresis (CIE)

RESUMO

The liver abscess is the most frequent extraintestinal complication of intestinal amoebiasis: its diagnosis is suggested by the clinical picture but it must be confirmed by paraclinic tests. Themost stringent diagnosis requires identification of E. histolytica. But this is possible only in a few cases. Serological tests greatly improve the diagnosis of this severe complication of amoebiasis. We compared the Enzyme Linfed Immunosorbent Assay and the Counterimmunoelectrophoresis techniques. Both techniques were used to detect amoebic antibodies in 50 control patients, 30 patients with liver abscess and 30 patients with intestinal amoebiasis. All the sera from control patients gave negative results in both techniques. When analysing the sera from patients with intestinal amoebiasis, 10 per cent of them were positive by ELISA but non by CIE. The sera of patients with liver abscess, we found that 90 per cent were positive by the ELISA method and 66.6 per cent by the CIE technique. In patients with amoebic liver abscess, the results showed that the ELISA was more sensitive than the CIE, as it presented a higher sensitivity (100 per cent) than that of the CIE technique (66 per cent).