PEHO syndrome (Progressive encephalopathy with Edema, Hypsarrhythmia, and Optic atrophy) is an autosomal recessive disorder leading to profound psychomotor retardation. The etiology and pathogenesis of the syndrome are unknown. The main clinical findings are severe hypotonia, brisk reflexes, convulsions, profound psychomotor retardation, subcutaneous edema, and absence or early loss of visual fixation. The nature of the syndrome is progressive and most patients die before the age of 15 years.