Title : From birth without hair or nails: A new case of pure ectodermal dysplasia
Abstract:
Introduction: Ectodermal dysplasias (ED) are a heterogeneous group of inherited disorders characterized by developmental abnormalities of ectodermal structures such as hair, nails, teeth, and sweat glands. Pure ectodermal dysplasia of nails and hair (PHNED) is an extremely rare subtype, defined by congenital nail dystrophy and severe hypotrichosis. Only about 20 cases have been reported worldwide.
Objective: To report a new case of pure ectodermal dysplasia involving nails and hair in a 2-year-old child.
Observation: A 2-year-old boy, born at term from a first-degree consanguineous marriage, presented with universal alopecia since birth and dystrophy of all twenty nails. Clinical examination revealed total absence of scalp, eyebrow, eyelash, and body hair, associated with dystrophic, curved nails. Teeth and sweat glands were normal, and systemic examination was unremarkable. Trichoscopy showed a complete absence of hair shafts and follicular openings. Scalp biopsy demonstrated atrophic hair follicles. Genetic testing could not be performed due to limited availability.
Discussion: Pure ectodermal dysplasia of nails and hair is an exceptionally rare genodermatosis that may be inherited in either autosomal recessive or dominant patterns, with variable clinical expression. Mutations in KRT85, HOXC13, or KRT74 genes have been identified in previously reported cases. The clinical findings in our patient are consistent with those described by Naeem et al., who reported a mutation in the KRTHB5 gene, and the histopathological features match those published by Lin et al. Genetic analysis would be helpful to confirm the mutation responsible, but this test is not yet available in our setting.
Conclusion: This case illustrates the classical features of pure ectodermal dysplasia of nails and hair, characterized by congenital alopecia and onychodystrophy. Diagnosis was based on clinical, trichoscopic, and histopathological findings. Genetic analysis, when available, could provide further diagnostic confirmation and improve understanding of this rare disorder.
