A case of keratitis–ichthyosis–deafness (KID) syndrome

Abstract

A 26-year-old Japanese woman was referred to our hospital with generalized hyperkeratosis associated with keratitis and a hearing defect. The patient was born from nonconsanguineous parents. Her skin was moderately hyperkeratotic at birth. During childhood, the thickness of the skin increased progressively. Bilateral sensorineural deafness was recognized at the age of 3 years. Visual disturbance was noted in later childhood, and corneal transplantations to the right eye were performed twice at the age of 16 and 25 years, but did not improve her visual acuity. There was no family history of similar disease. On physical examination, the patient showed erythematous, keratotic, scaly plaques on the cheeks, auricles, and perioral area (Fig. 1a). A grainy, spiculated, hyperkeratotic papillomatosis was particularly marked on the palms and the edge of the feet (Fig. 1b,c). The nails were slight hypertrophic, but not dystrophic. Ophthalmologic examination revealed the loss of eyebrows and eyelashes and hyperkeratotic lesions of the eyelids (Fig. 1d). Corneal opacification was observed in the right eye. Conjunctivitis and blepharitis with photophobia were also observed in both eyes (Fig. 1d,e). A skin biopsy specimen from the right lower thigh showed basket-wave hyperkeratosis and papillomatosis of the epidermis. Hyperkeratotic plugs were not observed (Fig. 1f). Laboratory data, including complete blood cell count, sedimentation rate, immunoglobulins and transaminases, urea, cholesterol, and triglycerides were normal. With informed consent, genomic DNA was extracted from blood samples. The complete open reading frame of the GJB2 gene was polymerase chain reaction amplified and sequenced. A transition mutation (148G --> A) was detected, resulting in a putative amino acid change from aspartic acid to asparagine at codon 50 (Fig. 2). The mutation was not present in her parents or two siblings. These clinical, pathologic, and genetic data supported the diagnosis of keratitis-ichthyosis-deafness syndrome.