Hystrix-like ithyosis deafness syndromeQ87.8

Hystrix-like-ichthyosis-deafness syndrome is a very rare, autosomal-dominantly inherited keratinization anomaly, characterized by connatal erythroderma with sensory sensorineural hearing loss, which later develops into ichthyosis with verrucous hyperkeratoses(ichthyosis hystrix). HID and KID(keratitis-ichthyosis-deafness syndrome) are genetically identical syndromes with different clinical expression of clinical symptoms.

In most diseases, a new mutation is present in the gene GJB2 (gap junction protein beta 2), which is located on chromosome 13q11-q12. This gene encodes the gap junction protein connexin 26 (see below GJB2). Connexins are components of cell-cell channels (gap junctions). In the case of a defect of the gap junctions, the regulation of cell growth and cell differentiation is disturbed. This leads to a reduced immune defence and an increased carcinogenic potential. Recent studies have shown that the genetic changes are identical to the known mutation of the KID syndrome ( keratitis-ichthyosis-deafness syndrome).

Congenital erythroderma. In later years development of extensive, verrucous, spike-like, grey-blackish hyperkeratosis, which may occur on all parts of the integument and also on the face. There is usually tender ichthyosiform scaling on the trunk.

Other symptoms: Lack or absence of body hair, nail dystrophies, incomplete dental anomalies and neurosensory hearing loss.

There is an increased tendency to infections, especially of the skin, as well as an increased tendency tothe formation of squamous cell carcinomas of the skin.

1. Geel M van et al (2002) HID and KID syndromes are associated with the same connexin 26 mutation. Br J Dermatol 146: 938-942
2. Todt I et al (2006) Neurotological and neuroanatomical changes in the connexin-26-related HID/KID syndrome. Audiol Neurootol 11: 242-248