The Clinical Manifestation of p.Asp50Asn Heterozygous Mutation of GJB2 Gene in 3 Members of a Family Is Similar to That of Clouston Syndrome.

Keratitis-ichthyosis-deafness (KID) syndrome has genetic heterogeneity, and the clinical manifestations of some patients may overlap with Clouston syndrome. A 34-year-old female patient came to our department with a complain of "sparse hair, rough skin, photophobia and deafness for more than 30 years." We found that the proband and two other family members (57-year-old mother and 4-year-old daughter) had similar clinical manifestations: systemic hair loss, generalized skin hyperkeratosis, especially in the metacarpophalangeal area. Subungual hyperkeratosis, finger/toenail dystrophy, as well as photophobia and epiphora. According to the investigation, one of the family members also had similar clinical manifestations (grandfather of the proband) and he's died. The other three members of the family had no hearing impairment, and all patients had typical nail dystrophy, hair loss and palmoplantar hyperkeratosis, similar like as seen in Clouston syndrome, so we suspected to diagnose the case as Clouston syndrome. However, after genetic testing, it was found that the proband, his mother and daughter all had p.Asp50Asn heterozygous mutations in the GJB2 gene, and no mutation was detected in GJB6. The modified diagnosis was KID syndrome.