Pontocerebellar hypoplasia type 2

Alternate names

Progressive microcephaly from birth extrapyramidal dyskinesia chorea epilepsy; PCH2

Definition

Pontocerebellar hypoplasia type 2 (PCH2) is a rare condition that affects the development of the brain.

Cause

PCH2 is caused by changes (mutations) in the TSEN54, TSEN2, TSEN34, or SEPSECS gene.

Inheritance

Autosomal recessive inheritance, a 25% chance

It is inherited in an autosomal recessive manner.

Signs and symptoms

• Signs and symptoms vary but may include microcephaly, developmental delay with lack of voluntary motor development, intellectual disability and movement disorders (i.e. chorea, dystonia, and spasticity).
• Affected people may also experience dysphagia (difficulty swallowing), impaired vision, seizures and an inability to communicate.
• Children with this condition often pass away prior to age 10 years, although survival beyond age 20 years has been reported.

Clinical presntation

For most diseases, symptoms will vary from person to person. People with the same disease may not have all the symptoms listed.

5%-29% of people have these symptoms

• Cerebral atrophy(Degeneration of cerebrum)
• Cerebral cortical atrophy(Decrease in size of the outer layer of the brain due to loss of brain cells)
• Death in childhood
• Simplified gyral pattern
• Ventriculomegaly

Diagnosis

The diagnosis of TSEN54-PCH is suspected in children with characteristic neuroradiologic and neurologic findings, and is confirmed by the presence of biallelic TSEN54 pathogenic variants.[1].

Treatment

• Treatment of irritability, swallowing incoordination, epilepsy, and central visual impairment is symptomatic.
• Physiotherapy can be helpful. [2].
• Adequate hydration during prolonged periods of high fever may help avoid rhabdomyolysis.

NIH genetic and rare disease info

• NIH info on Pontocerebellar hypoplasia type 2

Pontocerebellar hypoplasia type 2 is a rare disease.