Keratitis Ichthyosis Deafness (KID) Syndrome

A form of ectodermal dysplasia characterized by inflammation of the corneae (keratitis), skin scales, and deafness.

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Autosomal Dominant Form: Senter Syndrome; Ichthyosiform Erythroderma with Corneal Involvement and Deafness. Autosomal Recessive Form: Desmons Syndrome; Desmons-Britton Syndrome.

Exact incidence of either type unknown. Approximately 70 cases of the autosomal dominant form have been reported. The autosomal-recessive form is less common (approximately 35 cases have been described.)

The dominant form of KID is caused by heterozygous missense mutations in the connexin-26 gene GJB2 (“gap junction beta 2”). A deletion in the GJB6 gene, which is very close to GJB2, can also be responsible for the disorder (especially the recessive form). Sporadic cases are frequent.

Dominant GJB2 mutations can disturb the gap junction system of one or several ectodermal epithelia, resulting in erythrokeratoderma, sensorineural hearing loss, and keratitis. The GJB2 protein allows the creation of gap junctions between cells. The absence of these channels prevents potassium flux between cells of the inner ear, a process necessary for normal hearing.

Clinical picture and genetic testing (Cx26 test).

Common characteristics of both types of this syndrome include hyperkeratotic skin lesions, congenital sensorineural hearing deficits, and corneal opacity often requiring corneal transplant. The skin lesions start as erythematous, scaly patches on the face, ears, extensor surfaces of the limbs, palms, and soles, which later become brownish-yellow plaques. Ectodermal dysplasia is another major manifestation of KID syndrome. Most patients have partial alopecia, fragile and malformed nails, and small, malformed teeth. The recessive form also presents with hepatic cirrhosis, which may progress to the point of requiring liver transplantation by middle age, short stature, and mental retardation. Epidermal glycogen deposits were present in some patients with the recessive form.

Check mouth opening in the presence of perioral skin lesions. Check liver function in patients affected by the autosomal recessive form and also obtain a complete blood count (thrombocytopenia secondary to hypersplenism). Mental retardation may limit patient cooperation, and sedative/anxiolytic premedication as well as the presence of the primary caregiver for induction of anesthesia may be helpful.

Perioral hyperkeratotic plaques may limit mouth opening, making glottic visualization difficult. Hyperkeratotic, erythematous skin may prevent ECG electrodes or tape from adhering to the skin, thus making the securing of endotracheal tubes and IV catheters difficult. Needle electrodes, sutures, and/or rolls of gauze dressing to secure devices are options. Intravenous access may be difficult as a consequence of skin plaques. Hepatic dysfunction or failure should be evaluated. Generalized edema, ascites, high-output cardiac failure, impaired coagulation, electrolyte and glucose abnormalities, and altered pharmacodynamics and kinetics are a few of the many considerations in patients with liver dysfunction. Careful insertion of nasogastric tubes in the presence of esophageal varices.

Avoid drugs with predominantly hepatic metabolism and elimination if possible in patients with hepatic failure or use reduced doses (also applies for highly protein-bound drugs).

Erythrokeratodermia Variabilis: Genetic syndrome associated with deafness and keratosis caused by a mutation in connexin 31 (GJB3) (gene map locus at 1p32-p36).

Progressive Symmetric Erythrokeratodermia: Autosomal dominant disorder of cornification characterized by hyperproliferation of erythematosquamous plaques, symmetrically distributed on the head, extremities, and buttocks; penetrance is variable, and sporadic new mutations may represent 40% of cases.

Palmoplantar Keratoderma Deafness Syndrome: Genetic disorder characterized by early deafness, progressive keratosis of the palms and soles in mid-childhood; both a mutation in the gene encoding connexin-26 (13q11-q12) and the 7445A-G mutation of the mitochondrial serine tRNA gene MTTS1 can cause this disorder.

Ectodermal Dysplasia: A group of inherited disorders affecting at least two derivatives of the ectoderm.