MUSCLE-NERVE INVOLVEMENT IN AUTOSOMAL-DOMINANT PROGRESSIVE EXTERNAL OPHTHALMOPLEGIA WITH HYPOGONADISM

Sixteen members of a family with a history of autosomal dominant progr essive external ophthalmoplegia (adPEO) with hypogonadism were examine d, The muscular involvement commenced cranially and descended in relat ion to increasing disease duration, The neuromuscular signs were PEG, dysarthria, dysphonia, limb muscle weakness with wasting, absence of A chilles tendon reflexes, and distal vibration sensory loss, The electr omyogram (EMG) was myopathic in facial and proximal limb muscles. Neur ogenic involvement was suspected in a few tibial anterior muscles, Neu rography showed signs of axonal neuropathy correlated to clinical sign s. F-responses were reduced in number or absent in peroneal nerves, an d did not correlate to clinical signs or disease duration, Muscle biop sies in advanced cases had structural abnormalities of mitochondria, r agged-red fibers, and focal cytochrome c oxidase deficency. A combinat ion of muscle-nerve involvement with PEG, Achilles tendon areflexia, d istal vibration sensory impairment, myopathic EMG, and abnormally low sural nerve responses seems to be typical of this type of mitochondria l disorder. (C) 1996 John Wiley & Sons, Inc.