Palmoplantar hyperkeratosis and alopecia, also known as Clouston syndrome, is a form of ectodermal dysplasia. Ectodermal dysplasias are a group of syndromes with characteristic abnormalities of the ectodermal structures, including the hair, teeth, nails, sweat glands, cranial-facial structure, and hands. These genetic disorders can be inherited in an autosomal dominant or recessive manner.
Symptoms of palmoplantar hyperkeratosis and alopecia include thickening of the skin on the palms of the hands and soles of the feet, abnormal hair loss, fingernail and toenail defects, and changes in skin coloring. Unlike most forms of ectodermal dysplasia, palmoplantar hyperkeratosis and alopecia is associated with normal teeth and a normal ability to sweat. Hearing loss has been documented in some individuals with palmoplantar hyperkeratosis and alopecia.
Palmoplantar hyperkeratosis and alopecia is an inherited genetic disorder that is passed down among family members. Two gene candidates, the GJB6 gene and the GJB2 gene,bothon chromosome 13, have been linked to palmoplantar hyperkeratosis and alopecia in ethnically diverse populations. This disorder usually follows an autosomal dominant pattern of inheritance, meaning that only one copy of the defective GJB6 or GJB2 gene is needed for the disease to appear.
Palmoplantar hyperkeratosis and alopecia is a rare disorder, with the exact incidence currently unknown. Cases of palmoplantar hyperkeratosis and alopecia have been found among people of French, French-Canadian, Spanish, African, Scottish-Irish, Indian, and Malaysian ancestry, and possibly others that have not been documented.
Alopecia, Clouston syndrome, connexin, ectodermal dysplasia, GJB2, GJB6, hidrotic ectodermal dysplasia, palmoplantar hyperkeratosis, palmoplantar keratoderma.