Evaluation of six serological tests in diagnosis and postoperative controlof pulmonary hydatid disease patients

Latex agglutination (LA), passive hemagglutination (PHA), immunoelectrophor esis (IEP) and specific IgE, IgM, IgG enzyme-linked immunosorbent assay (EL ISA) test for diagnosis and postoperative follow-up of 79 patients with sur gically confirmed pulmonary hydatidosis were evaluated. Specific IgG ELISA was the most sensitive test (83.5%) and the least sensitive tests were spec ific IgE ELISA (44.3%) and IEP (50.6%). The specificity obtained for all th e serologic test was above 97% in all cases. The greatest number of false p ositives in all tests (except IEP) occurred in patients with Taenia saginat a and Taenia solium cysticerci infestations and in patients with lymphoma a nd leukemia. Specific IgG ELISA demonstrated the highest negative predictiv e value (93.8%). No statistically significant differences (p > 0.050) were found in the sensitivity of the tests when patients with only one cyst and patients with various cysts were compares. Considering only the patients wi thout relapse, the percentage of seropositive patients increased in all tes ts at 1 and 3 months after surgery. After that time the percentage of serop ositive patients decreased. At 48 months after surgery all patients without relapse became negative in IEP, specific IgG ELISA, and specific IgM ELISA . The antibody titers in all seropositive patients increased during the 3 m onths after surgery. From these 3 months onward, antibody levels decreased in all serologic tests studied in the group of patients without relapse. Th e patients who had relapse during the first year after surgery presented pe rsistently elevated antibodies titers in all postoperative sera. The antibo dy titers of the patients who relapsed between the third and fourth years a fter surgery decreased progressively the third month after surgery, and inc reased in the serum obtained at the moment of relapse diagnosis. Our result s show that persistence of elevated antiboby titers in patients with pulmon ary hydatidosis in the year after surgery or titer increase after a progres sive decrease are indicative of relapse od reinfection. (C) Elsevier Scienc e Inc.