Report of the Cuba Neuropathy Field Investigation Team: A Case-Control Study of 300

In early 1992, ophthalmologists in the western Cuba province of Pinar del Rio reported several cases of bilateral optic neuropathy, predominantly in adult men. Initial diagnoses included retrobulbar optic neuritis and tobacco-alcohol amblyopia. Over the subsequent six months, 14-36 new patients were reported per month in the Pinar del Rio region with optic neuropathies manifested with decreased visual acuity, color vision, central or cecocentral scotomas, and ultimately optic disc pallor. In some cases, mild disc hyperemia and mild disc edema were observed. The patients also had other neurologic features, including paresthesias and dysesthesias, reflecting a predominantly sensory peripheral neuropathy and sensory myelopathy. In mid-1992, a commission of specialists was convened to study the disease, and concluded that the illness should be considered a toxicnutritional neuropathy. During 1992, 4 72 cases were reported, 72% of them from Pinar del Rio.