Severe Monilethrix Associated with Intractable Scalp Pruritus, Posterior Subcapsular Cataract, Brachiocephaly, and Distinct Facial Features: A New Variant of Monilethrix Syndrome?

Abstract

Monilethrix is a rare developmental hair shaft defect characterized by small elliptical node-like deformities with increased hair fragility resulting in partial or diffuse alopecia. The disorder is usually transmitted in an autosomal dominant fashion with incomplete penetrance and variable expressivity, but autosomal recessive inheritance has also been reported. It is thought to be without systemic involvement, whereas keratosis pilaris and follicular papules are almost invariably associated features. We describe an instance of monilethrix in a 9-year-old boy from consanguineous parents, characterized by universal dystrophic alopecia associated with intractable scalp pruritus, diffuse keratosis pilaris, and bilateral posterior subcapsular cataracts. His disease was further characterized by physical underdevelopment and distinct features of hypertelorism, a wide-based nose, long philtrum, relatively large mouth with thick lower lip, enlarged forehead, small, receding chin, short neck, and rounded (ultrabrachycranial) skull. The findings in our patient suggest that "monilethrix syndrome" is an appropriate term for defining the instances of monilethrix associated with other abnormalities. We conclude that our patient may represent a new and severe, autosomal recessive variant of monilethrix syndrome.