OXFENDAZOLE TREATMENT FOR CYSTIC HYDATID-DISEASE IN NATURALLY INFECTED ANIMALS

Few chemotherapeutic agents are available for the medical management o f hydatid disease caused by the parasite Echinococcus granulosus. In o rder to test the potential of oxfendazole for the treatment of infecti on with this parasite, nine infected goats and four sheep were given o xfendazole twice weekly at a dose of 30 mg/kg of body weight for 4 wee ks and monitored by ultrasound for an additional 4 weeks. Efficacy was finally evaluated by postmortem examination, including determination of protoscolex viability and cyst wall histology. In treated animals, protoscolices were dead or absent in 97% of cysts from oxfendazole-tre ated animals compared to 28% of cysts from untreated control animals. On postmortem examination, 53% of cysts from treated animals were foun d to be grossly degenerate. A sample of those cysts that appeared pote ntially viable all demonstrated evidence of severe damage to the cyst wall. By light microscopy, cysts showed severe disorganization of the adventitial layer with invasion of inflammatory cells and in some case s frank necrosis,vith no apparent adventitial layer. The follow-up per iod for assessment of the drug's ability to cause complete degeneratio n and resorption of cysts was relatively short. This study, however, i ndicates that oxfendazole is at least as effective as and is easier to administer than albendazole for the treatment of hydatid disease.