Clouston Syndrome

At a glance

It is a medical condition characterized by the triad of palmoplantar hyperkeratosis, nail dystrophy, and alopecia. Facial appearance, teeth, and sweating are normal.

Synonyms

Fischer-Jacobsen-Clouston Syndrome; Hidrotic Ectodermal Dysplasia Syndrome; Alopecia Congenita with Keratosis Palmoplantaris Syndrome; Keratosis Palmaris with Drumstick Fingers Syndrome; Palmoplantar Keratoderma and Clubbing Syndrome.

History

This medical condition was first described by Howard Rae Clouston (1902-1971), a graduate from McGill University, Montréal, Québec, Canada, in 1911. He was a family practitioner who conducted research on Ectodermal Dysplasia.

Incidence

Unknown. A higher incidence has been reported in the French Canadian population, but it occurs in all ethnicities.

Genetic inheritance

Autosomal dominant. The defect has been linked to 13q11-q12.1.

Pathophysiology

Abnormality in the molecular structure of keratin seems to be responsible for the disease.

Diagnosis

Based on the typical clinical features and family history.

Clinical aspects

In contrast to the X-linked form of ectodermal dysplasia (anhidrotic ectodermal dysplasia), most of the affected patients have normal sweat and sebaceous glands, and the teeth are usually only mildly affected (in contrast to the first description by Clouston). However, as in other forms of ectodermal dysplasia, the patients suffer from severe dystrophy of nails (thickened, striated, very slow growing, often discolored) and hair (resulting in total alopecia, sometimes in infancy but usually after puberty). Ultrastructural analysis of the hair shows an altered organization of hair fibrils with loss of the cuticular cortex suggesting a biochemical defect in the keratin of the integumentary system. Skin changes include palmoplantar hyperkeratosis, which can involve the periungual area and result in thickening of the fingertips with the aspect of clubbing. Skin hyperpigmentation is common over the joints.

Precautions before anesthesia

Although no specific reports for this disease exist, because of mild depression of the immune system and hypoplasia/absence of the respiratory mucus glands, other forms of ectodermal dysplasia are often associated with a predisposition to respiratory tract infections, which can be life-threatening. Although no such reports exist specifically for this syndrome, it should be kept in mind when assessing the patient.

Anesthetic considerations

Altered heat regulation does not seem to be a problem in these patients because sweat glands are functional. Direct laryngoscopy and tracheal intubation may be difficult because of maxillary and/or mandibular abnormalities. Because of hypoplasia/absence of mucous glands in the respiratory tract, humidified air should be used for general anesthesia and in the postanesthesia care unit.