Unilateral optic atrophy presumed secondary to schistosomiasis of the optic nerve

Schistosomiasis, a parasitic disease, is endemic in many parts of the world. Schistosomal eggs may be found in almost any organ or tissue in the body, including the eye. The presence of schistosomal eggs in the eye can produce granuloma formation and inflammatory sequelae.

A 63-year-old male had contracted schistosomiasis 40 years earlier while on active military service in the Philippines. Schistosoma japonicum eggs were isolated from his stools and military records indicated that the disease responded well to treatment with antimony potassium tartrate. The patient has gradually lost vision with his left eye over 15 years without the benefit of a complete optometric and medical diagnosis.

CT scan suggested the likelihood of "subtle changes in the left optic nerve medially, possibly related to tumor invasion." Further evaluation and coordinated clinical thinking with other eye and medical practitioners led to the suspected diagnosis of schistosomal granuloma in the left optic nerve. In addition, the patient was legally blind from the consequences of glaucoma and its surgical intervention in his fellow eye.

Although over 200 million people are infected with schistosomiasis, the United States is not an area where schistosomiasis is endemic. It is, however, endemic in parts of South America, Africa, Asia and the Caribbean Islands. Patients who have been in endemic areas with unexplained ophthalmic findings or systemic findings that could be related to granuloma formation or inflammatory sequelae of disease should have schistosomiasis included in their differential diagnosis.