Unilocular Hydatid Cyst Disease in the Mid-South

UNILOCULAR hydatid disease is caused by the larval stage of the canine intestinal tapeworm, Echinococcus granulosus . The disease is usually found as a solitary, fluid-filled bladder type of cyst situated in the liver, although localization may occur in other organs, especially the lungs. Such a cyst can grow and become large enough to cause a variety of clinical signs related, in part, to the pressure exerted by the cyst. Humans usually obtain this infection by ingesting the Echinococcus ova that have been passed with the feces of dogs. Sheep are excellent intermediate hosts for E granulosus , and the sheep dog that has been fed the entrails of infected animals has been implicated as an important source of human infections. The majority of medical references published in the United States consider locally acquired hydatid disease to be uncommon in humans in the 48 contiguous states, with the infection most likely to