Clinical Course of a Cohort in the Cuban Epidemic Optic and Peripheral Neuropathy

Abstract

Nearly 51,000 Cubans were afflicted during an outbreak of an optic neuropathy (ON) and peripheral neuropathy (PN) between 1991 and 1993. We re-examined 14 of 20 affected individuals 16 months after an initial evaluation. The optic features were painless symmetric vision loss with poor visual acuity, color vision loss, central or cecocentral scotoma, optic disc pallor, and nerve fiber layer drop-out. The neurologic symptoms included stocking-glove sensory changes, hearing loss, leg cramps, sensory ataxia, hyperactive or absent reflexes, and complaints of memory loss. Two of 11 ON probands tested harbored Leber's hereditary optic neuropathy (LHON)-associated mitochondrial DNA mutations. All patients had received multivitamin therapy. We performed comparisons using the paired two-tailed t test. On re-examination, 12 of 14 patients demonstrated improvement. One patient remained unchanged. One woman with the nt-3460 mtDNA mutation showed a decline in vision. In patients not harboring mtDNA mutations, overall visual acuity, color vision, and peripheral neuropathy manifestations improved significantly (p < 0.001 for each manifestation). Most of the patients with Cuban ON and PN improved on multivitamin therapy. The significance of the mtDNA mutations is unclear. In the 2 LHON patients, manifestation of the disease may have been precipitated by nutritional deficiency. Patients with poor recovery or further deterioration should be evaluated for other factors, including poor vitamin therapy compliance and alternative diagnoses.

Persistence of tropical ataxic neuropathy in a Nigerian community

“…The optic form and the peripheral form of the epidemic were considered distinct39 with different risk factors 2138The aetiology of the syndrome was not conclusively determined although reports suggest that the epidemic subsided after vitamin supplementation for the whole population 38.…”

Neuromuscular diseases and disorders of the alimentary system

“…It is likely that the recent epidemics of nutritional neuropathies observed in the Caribbean and Cuba are variations of the same syndrome. 17,104,167 The syndrome is speculated to result from distal degeneration of both central and peripheral processes of sensory neurons. Distal sensory loss, hyporeflexia at the ankles, hyperreflexia at the knees, and gait ataxia occur.…”

HIV-associated neuromuscular weakness syndrome

“…Alternatively, genetic factors may predispose patients to additive neurotoxicity of mitochondrial toxins. For example, Cuban blindness syndrome is more likely to develop in patients with pre-existing mitochondrial mutations [28].…”