DIAGNOSTIC-CRITERIA AND GENETICS OF THE PEHO SYNDROME

The PEHO syndrome (progressive encephalopathy with oedema, hypsarrhyth mia, and optic atrophy) is a recently recognised disorder of unknown b iochemical background. Diagnostic features have been found in neurorad iological and neuropathological studies, which show characteristic sev ere cerebellar atrophy. In combined neuroradiological and ophthalmolog ical studies, 10 out of 21 possible PEHO patients fulfilled the criter ia for true PEHO syndrome. All were abnormal at birth showing hypotoni a, drowsiness, or poor feeeding. Head circumference was normal, but us ually dropped to 2 SD below average during the first year of life. Vis ual fixation was either absent from birth or lost during the first mon ths of life. Nine patients had peripheral oedema in early childhood. T he mean age of onset of infantile spasms was 4-9 months. All patients were extremely hypotonic and no motor milestones were reached. Patella r reflexes were brisk. Brain stem and somatosensory evoked potentials were abnormal in each case studied, cortical responses of somatosensor y evoked potentials could not be elicited, and motor conduction veloci ties became delayed with age. Altogether 19 PEHO patients were found i n 14 Finnish families. Autosomal recessive inheritance is likely.