Neuroretinitis with secondary retinal venous stasis in a patient with Schistosomiasis

Schistosomiasis, one of the most important parasitic diseases in humans, is caused by the trematode parasites. Common manifestations include gastrointestinal and genitourinary symptoms while ophthalmologic involvement is rare. Here we report a case of retinal vein occlusion and neuroretinitis secondary to a schistosomiasisis infection.

A healthy 23-year-old man presented with headache and decreased vision in his right eye. Ophthalmic examination revealed a swollen disc, engorged retinal veins with retinal hemorrhages in all quadrants and macular edema with hard exudates ('macular star'). Fluorescein Angiography demonstrated a hot disk and an irregular pattern of filling defects along a major retinal vein. Further questioning revealed that a few months earlier, the patient had returned from an endemic area and was found seropositive for schistosomiasis.

In this case of neuroretinitis and secondary retinal venous stasis, the presumed underlying mechanism is associated with embolization of Schistosoma eggs or deposition of immune complexes. Although ophthalmic manifestations of schistosomiasis are rare, awareness should be maintained especially among world-travelers with unusual ocular findings.