Post operative surveillance of human hydatidosis: evaluation of immunodiagnostic tests

We investigated the kinetics of antibodies detected by indirect hemagglutination (IHA), IgE Elisa and immunoelectrophoresis (IEP) in patients with hydatid disease operated on and continuously followed in the pre-operative and post-operative periods. In the pre-operative phase the IgE Elisa test was found to be adequately sensitive (68.4%) compared with IHA (79%), with a ratio of IgE Elisa/IHA positivity of 87%, while IEP was positive in 55.3% of cases (IEP/IHA ratio = 70%). During post-operative follow-up IHA became negative late in patients who were cured (7 out of 11 were still positive after 4 yrs), whereas IEP and IgE Elisa became negative within 2 yrs of operation (apart from 1 patient with a persisting positive IgE Elisa 3 yrs later). However, IgE Elisa appeared clearly more sensitive in revealing postoperative recurrences (13 out of 13 patients had positive IgE Elisa, vs. 6 out of 13 IEP).