Optic Atrophy in Classical Methylmalonic Acidemia (.pdf)

"Methylmalonic acidemia (MMA) is an autosomal recessive, metabolic failure to process various amino acids and lipids. Classical MMA results in methylmalonyl CoA mutase deficiency, preventing the vitamin B12-dependent conversion of methylmalonyl CoA to succinyl CoA, required in Krebs cycle. Patients typically present in early infancy with lethargy and failure to thrive. Long-term complications include renal failure (CRF) and encephalopathy. Only 4 cases of optic atrophy (OA) have been reported. With improved survival of patients offered advanced treatment, OA needs to be identified so that prophylactic/therapeutic intervention, when available, can be incorporated into management protocols. The purpose of this study is to identify and determine the prevalence of OA in classical MMA."