Myasthenia gravis presenting with unusual neurogenic muscle atrophy

We report a patient with myasthenia gravis who had neurogenic muscle atrophy in association with external ophthalmoplegia and weakness of the upper limbs. Neurogenic changes in the limb muscles were found on needle electromyography and histological studies. Symptoms improved and atrophy of the limbs diminished after intravenous immunoglobulin and oral corticosteroid therapy. We concluded that functional interruption of the neuromuscular junction caused the neurogenic muscle atrophy and that this was relieved by appropriate therapy.