A 16-year-old male presented with failure to thrive, ptosis and ophthalmoplegia. The weight and stature of the patient were compatible with 7 years of age. Routine work-up including hormone assays were normal. Physical examination revealed retinitis pigmentosa and an open angle glaucoma. Audiometry showed some degree of bilateral neural hearing loss. Protein, and lactate dehydrogenase levels of the patient's cerebrospinal fluid were 110 mg/dl, and 270 IU, respectively. Electrocardiography was also abnormal, see the above tracings. His family history was unremarkable. Muscle biopsy showed ragged red muscle fibers.
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