Multiple sclerosis-like disorder in OPA1-related autosomal dominant optic atrophy.

Autosomal dominant optic atrophy (ADOA) is a progressive ophthalmologic disorder caused in two-thirds of the cases by a mutation in the optic atrophy 1 ( OPA1 ) gene, a nuclear gene encoding a mitochondrial protein.1 We report a patient in whom an OPA1 mutation was responsible for bilateral optic atrophy associated with multiple sclerosis–like (MSL) features. In addition, biochemical studies performed on fibroblasts from this patient showed a significant mitochondrial coupling defect associated with reduced ATP production and respiratory function in comparison to controls. ### Case report. A 44-year-old man was referred to our neurology unit for sudden onset of pain in the lower left limb. His medical history was noteworthy for an insidious, bilateral loss of visual acuity that had appeared 1 year earlier, followed a few months later by trigeminal neuralgia. At that time, the brain MRI was normal. There was no family history of ocular or neurologic diseases. Neurologic examination revealed proprioceptive dysfunction, brisk tendon reflexes, and ankle clonus in the left lower limb. The gait was spastic and the results of motor examination revealed only abnormal tone. Ophthalmologic examination indicated visual acuity …