Ectrodactyly-Ectodermal Dysplasia-Clefting Syndrome

An 11-year-old girl presented with central clefting and syndactyly of the third and fourth digits of the right hand (A); sparse, fine blond scalp hair (B); sparse eyebrows; and numerous dental caries. Past health was unremarkable except that she had stenosis of the nasolacrimal ducts, which required probing when she was 1 year old. Her mother also had somewhat sparse and fine scalp hair and similar hand malformations with ridged and slow-growing nails, as well as mild conductive hearing loss.

The cardinal features of ectrodactyly-ectodermal dysplasia-clefting (EEC) syndrome are ectrodactyly, stenosis or atresia of the nasolacrimal duct, and ectodermal dysplasia, with cleft lip or palate appearing slightly less consistently. Ectrodactyly refers to the congenital absence of all or part of a digit. One or more central digits are generally involved, producing the characteristic “split hand” appearance. Cutaneous or bony syndactyly may also be present.

Features of anhidrotic ectodermal dysplasia include sparse, thin blond scalp hair; sparse eyebrows and eyelashes; hypodontia; microdontia; abnormalities of the dental enamel; peg-shaped teeth; hypoplastic nipples; dry skin with inability to sweat; and dysplastic nails. Other manifestations of the EEC syndrome include anomalies of the kidneys, urinary tract, and genitalia. Conductive hearing loss, hypogonadism, and diabetes insipidus also occur. Mentation is usually normal. The condition is inherited as an autosomal dominant trait with incomplete penetrance and extremely variable expressivity.