ALVEOLAR ECHINOCOCCOSIS - EM2(PLUS)-ELISA(TM) AND EM18-WESTERN BLOTS FOR FOLLOW-UP AFTER TREATMENT WITH ALBENDAZOLE

Eleven cases of alveolar echinococcosis (Echinococcus multilocularis i nfection) with non-resectable lesions but neared with albendazole for 17 to 69 months were followed-up clinically and serologically for 4.5- 11.5 years. Based on the clinical outcome and computerized tomography (CT) scanning, they were divided into 4 groups of 2 cured cases, 5 sta bilized cases, 3 cases with recurrences, and one treatment failure. Fo rty-seven sequentially collected sera from the II cases were analysed by sequential enzyme-linked immunosorbent assay (ELISA) using Em2(plus ) antigen (Em2(plus)-ELISA(TM)) and Western blotting to detect antibod y response against Em18 (EM18-Western blots). The antibody levels in o ne of the cured and 2 of the stabilized cases fell below the cut-off l evel in the Em2(plus)-ELISA(TM) 4.5-6 years after effective treatment, whereas all other cases, Including 2 of those with recurrences, showe d large reductions initially but increased again during the follow-up period. EM18-Western blots of the 2 cured cases and 2 of the stabilize d cases became negative. IgG subclasses with responses against Em18 wh ich fell to zero included IgG1 (2), IgG3 (one) and IgG4 (one). All oth er cases showed no decrease in antibody response against Em18. There w ere, in general, reasonably reliable correlations between the success or failure of chemotherapy and antibody responses by EM2(plus)-ELISA(T M) and Em18-Western blots. These results suggest that both Fm Em2(plus )-ELISA(TM) and Em18-Western blot are potentially useful in evaluating and predicting the efficacy of chemotherapy.