HIDEA syndrome
# HIDEA syndrome

HIDEA syndrome is a syndrome characterised by hypotonia, hypoventilation, intellectual disability, dysautonomia, epilepsy, and eye abnormalities. It is caused by the mutation of the P4HTM gene on chromosome 3.

## Presentation

This syndrome causes intellectual disability and affects the eyes, musculoskeletal system, and face.

Eyes

* Strabismus
* Difficulty fixing the eyes on an object

Face

Facial features gradually become coarser during childhood.

Musculoskeletal system

* Hypotonia
* Planovalgus
* Contractures in elbow joints
* Interphalangeal joint hypermobility

Other associated features include hypoventilation, obstructive and central sleep apnea and dysautonomia.

## Genetics

This condition is caused by mutations in the Prolyl 4-hydroxylase, transmembrane (P4HTM) gene. This gene is located on the short arm of chromosome 3 (3p21.3).

The inheritance of this condition is autosomal recessive.

## Diagnosis

The diagnosis may be suspected on clinical grounds.

It is made by sequencing the P4HTM gene.

## Management

There is presently no curative treatment. Management is supportive.

## Epidemiology

The prevalence is not known but this is considered to be a rare disease. Only 12 patients have been reported to date.

## History

This condition was first described in 2014. The causative mutation was discovered in 2019.

