echinococcosis /ekī′nōkokō″sis/ [Gk, echinos, prickly husk, kokkos, berry, osis, condition] , an infestation, usually of the liver, caused by the larval stage of a tapeworm of the genus Echinococcus. Dogs are the principal hosts of the adult worm; sheep, goats, horses, camels, cattle, rodents, and deer are the natural intermediate hosts for the larvae. Humans, especially children, can become infested with larvae by ingesting eggs shed in the stool of infected dogs and cats or by petting or handling household dogs or cats. The disease is most common in countries where livestock is raised with the help of dogs. Fluid-filled cysts form in affected organs such as the liver, lungs, brain, bones, or heart. Also called hydatid disease, hydatidosis. See also cysticercosis, tapeworm infection. ▪ OBSERVATIONS: Clinical manifestations and prognosis vary, depending on the tissue invaded and the extent of infestation. Diagnosis is made by skin tests for sensitivity, serological tests, radiological evidence of cyst formation, and identification of larval cysts in infected tissue. ▪ INTERVENTIONS: Treatment is an extended course of benzimidazole; puncture, aspiration, injection, and reaspiration of cysts; or careful removal of cysts, avoiding rupture of a cyst, which could cause severe allergic reactions or disseminate infection. ▪ PATIENT CARE CONSIDERATIONS: The disease can be prevented by avoiding contact with infected dogs, deworming pet animals, and preventing dogs from eating carcasses of infected intermediate hosts.
