Intraocular Echinococcus multilocularis.
Alveolar hydatid disease, caused by the organism Echinococcus multilocularis, is a potentially lethal helminthic infection. After initial hepatic infestation, the organism may spread locally and hematogenously to distant sites. Death occurs secondary to hepatic failure, local extension into vital structures, or metastasis to the brain or lungs. A 67-year-old male Alaskan Eskimo developed decreased visual acuity secondary to a choroidal mass in the right eye eight years after an initial diagnosis of alveolar hydatid disease and four years before the development of symptomatic cerebral metastasis. A pathologic examination disclosed characteristic parasitic membranes involving the posterior pole of the right eye. To our knowledge, this is the first report of ocular involvement in alveolar hydatid disease.