title: A novel dominant and a de novo mutation in the GJB2 gene (connexin-26) cause keratitis-ichthyosis-deafness syndrome: implication for cochlear implantation.
abstract: OBJECTIVE
  Keratitis-ichthyosis-deafness (KID) syndrome is a rare congenital disorder, characterized by hyperkeratosis and erythrokeratoderma associated with profound sensorineural hearing loss. Additional concomitant phenomena of the KID syndrome are dystrophic nails, dental abnormalities, scarring alopecia, and vascularizing keratitis. The disorder is caused by mutation in the GJB2 gene (connexin-26), a gap junction protein. The aim of this study was to explore the feasibility and procedure of cochlear implantation in patients with KID syndrome and to assess the genetic causes.
  
  
  METHODS
  Retrospective case review.
  
  
  METHODS
  Tertiary referral center. Cochlear implant program.
  
  
  METHODS
  We report on 2 cases of KID syndrome with congenital profound hearing loss. A 50-year-old woman with skin necrosis and implant extrusion 5 years after cochlear implantation and a 10-month-old infant girl with bilateral deafness, alopecia, bright light sensitivity, and congenital dermatosis.
  
  
  METHODS
  Genetic analysis. Cochlear implantation.
  
  
  METHODS
  Mutation analysis, surgical suitability, and hearing rehabilitation.
  
  
  RESULTS
  We detected a novel heterozygous missense mutation (Ile30Asn) in Patient 1 and a de novo mutation (Asp50Asn) in the GJB2 gene (connexin-26) in Patient 2. To decrease the risk of skin flap necrosis, we describe alternative surgical cochlear implantation techniques with a novel very thin receiver/stimulator (Nucleus CI 513; Cochlear Corp.). The postoperative course of both patients has been without any problems until now.
  
  
  CONCLUSIONS
  The combination of the cutaneous lesions with visual and auditory impairment demands to diagnose impaired hearing as early as possible. It would be helpful to search for KID syndrome in dealing with patients with deafness, skin lesions of unknown cause, and wound healing problems to choose the right method of surgical treatment and subsequent aftercare.
authors.affiliation: Department of Otorhinolaryngology, Head and Neck Surgery University Medical Center Freiburg, Freiburg, Germany. susan.arndt@uniklinik-freiburg.de
authors.forename: Susan
authors.initials: S
authors.lastname: Arndt
authors.forename: Antje
authors.initials: A
authors.lastname: Aschendorff
authors.forename: Christian
authors.initials: C
authors.lastname: Schild
authors.forename: Rainer
authors.initials: R
authors.lastname: Beck
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Maier
authors.forename: Roland
authors.initials: R
authors.lastname: Laszig
authors.forename: Ralf
authors.initials: R
authors.lastname: Birkenhäger
mesh_terms: D019929:Cochlear Implantation; D000072259:Connexin 26; D017630:Connexins / Q000235:genetics*; D004252:DNA Mutational Analysis; D003638:Deafness / Q000235:genetics* / Q000473:pathology / Q000601:surgery; D005260:Female; D006310:Hearing Aids; D006312:Hearing Loss, Bilateral / Q000235:genetics / Q000473:pathology; D006801:Humans; D007057:Ichthyosis / Q000235:genetics* / Q000473:pathology; D007223:Infant; D007634:Keratitis / Q000235:genetics* / Q000473:pathology; D008875:Middle Aged; D009154:Mutation / Q000502:physiology*; D020125:Mutation, Missense / Q000235:genetics / Q000502:physiology; D010787:Photosensitivity Disorders / Q000235:genetics / Q000473:pathology; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012535:Scalp / Q000473:pathology; D013577:Syndrome
chemical_list: D017630:Connexins; C000607042:GJB2 protein, human; D000072259:Connexin 26