Definition:

The PEHO syndrome (progressive encephalopathy with oedema, hypsarrhythmia, and optic atrophy) is a rare autosomal recessive neurodegenerative disorder that presents in infancy with hypotonia, seizures, peripheral oedema, characteristic dysmorphic features, and poor visual response. It is characterized by extreme cerebellar atrophy due to almost total granule neuron loss. A missense mutation in ZNHIT3 was identified as the primary cause of PEHO syndrome.