PEHO syndrome


PEHO syndrome is a rare neurodegenerative condition which usually begins within the first few weeks of life. The condition takes its name from the following features: progressive encephalopathy with (O)edema, hypsarrhythmia and optic atrophy (PEHO).

Progressive encephalopathy is the term used to describe degenerative changes which take place in brain tissue. In PEHO syndrome, these changes characteristically occur in the cerebellum. The cerebellum is important for maintaining posture, coordinating head and eye movements and fine-tuning of muscles.


Medical text written September 2002 by Contact a Family. Approved September 2002 by Dr S Robb. Last updated January 2009 by Dr S Robb, Consultant Paediatric Neurologist, Great Ormond Street Hospital, London, UK.

What are the symptoms?

Infants with PEHO syndrome may become increasingly floppy (hypotonia) and lose control of their muscles. The muscles supporting the head become floppy and weak and rolling over, sitting, standing and walking are rarely accomplished. Oedema or swelling of the hands, feet and face is also a feature of PEHO syndrome which may be transient or permanent.

Another feature of PEHO syndrome is the occurrence of infantile spasms. These are a distinctive type of epileptic seizure characterised by brief, but often repetitive, muscle contractions usually involving the head, trunk, and extremities. They occur in association with a particular pattern on EEG examination known as hypsarrhythmia. More typical seizures also occur in PEHO syndrome and may begin from birth to 12 months. Infants with PEHO syndrome gradually lose their ability to see (optic atrophy). Visual fixation is either absent at birth or lost during the first months of life, leaving infants with wandering and upward-turning eyes. Learning difficulties (see entry Learning Disability) have also been associated with PEHO syndrome. These become apparent at an early stage and usually affect language skills.

At birth, neonates are severely floppy, have feeding difficulties and are very drowsy. Their appearance is characterised by an expressionless, pear-shaped face with narrow forehead, broad, puffy cheeks and receding chin. The nose is small and upturned and the mouth is constantly open with a curved upper lip. Earlobes are outward turning. Although the head size is normal at birth, it usually becomes smaller (microcephaly) during the first year and the face becomes narrower with time.

How is it diagnosed?

The major diagnostic criteria for PEHO syndrome include changes in the brain, notably in the cerebellum (cerebellar atrophy) and progressing to the brain stem. This may be identified by magnetic resonance imaging (MRI) scan or at post-mortem. A diagnosis of PEHO-like syndrome may be given to those infants who look similar to infants with PEHO syndrome but who may have milder clinical features and fail to show the progressive cerebellar atrophy on brain MRI diagnostic of PEHO syndrome.

A number of conditions share similar features with PEHO syndrome including Joubert syndrome, autosomal recessive cerebellar hypoplasia, olivo-pontine cerebellar atrophies and carbohydrate-deficient glycoprotein (CDG) syndromes.

Inheritance patterns and prenatal diagnosis

Inheritance patterns
PEHO syndrome is thought to be inherited as an autosomal recessive trait.

Prenatal diagnosis
None available.

Is there support?

There is no support group for PEHO syndrome in the UK. Cross-referrals to other entries in Contact’s directory are intended to provide relevant support for those particular features of the disorder. Organisations identified in those entries do not provide support specifically for PEHO syndrome.

Families can use Contact’s freephone helpline for advice, information and, where possible, links to other families. To meet other families with disabled children, join Contact’s closed (private) Facebook group.

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