Gyrate atrophy of the fundus is a rare autosomal recessive disease characterized by deficiency of ornithine-δ-aminotransferase. Ornithine-δ-aminotransferase deficiency causes hyperornithinemia which results in progressive chorioretinal atrophy. Plasma levels of ornithine are elevated. Based on these observations, we describe the diagnosis of a patient with gyrate atrophy of the choroid and retina. This is the first report of Gyrate atrophy in Cuba, diagnosed by ornithine levels in blood and the ophthalmologist assessment.

The gene is expressed in the neuroretina and in the retinal pigment epithelium (RPE) and encodes for the mitochondrial and pyridoxal phosphate-dependent enzyme ornithine aminotransferase, which is necessary for the conversion of ornithine into glutamate and proline. Consequently, OAT gene mutations result in hyperornithinemia, typically with a 10-20-fold elevation of plasma ornithine levels.

Hyperornithinemia and ornithinuria were not recognized as the biochemical counterparts of this disorder until the report of Simell and Takkin, in 1973, 85 years after the initial ophthalmologic description. Several studies suggest that an arginine-restricted diet or a low-protein diet may slow the progression of chorioretinal lesions and visual loss in gyrate atrophy. Most patients seem not to be responsive to pyridoxine; however, a few studies report of pyridoxine-responsive patients presenting with a reduction of ornithine level after pyridoxine substitution.

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