ESPE Abstracts

Background: Ectodermal dysplasia is considered as an inherited multi-systemic disorder affecting tissues derived from ectoderm (skin, hair, teeth, nails and sweat glands). There are many genes involved in genetic background of this disorder with variable modes of inheritance. The thrombospondin-type laminin G domain and epilepsy- associated repeats (TSPEAR) gene have been found in some patients with this disorder with interesting variable phenotypic spectrum. Biallelic TSPEAR variants present either with sensorineural hearing loss or with involvement of ectodermal-derived structures such as skin, hair, nails, and teeth. The following case report aims at showing the phenotypic features of this mutation with novel association with atypical genitalia.

Case presentation: A 3-year-old boy presented to Pediatric Endocrinology clinic at Alexandria University Hospitals. His parents sought surgical consultation due to bilateral arrested testes (inguinal) and small sized penis. On clinical examination, external genitalia showed micropenis and bilateral palpable mid-inguinal testes (average sized for age). Furthermore, extragenital examination showed frontal bossing, fine sparse hair, thin fine eyebrows, brittle nails and conical shaped teeth. He had normal sweating and hearing. As a rare presentation of atypical genitalia, hormonal profile before and after HCG stimulation showed normal testosterone response with high testosterone/ dihydrotestosterone ratio. Inguinoscrotal ultrasonography showed average size and vascularity of both inguinal testes. Whole genome sequencing showed ectodermal dysplasia 14, hair/tooth type with or without hypohidrosis (OMIM: 618180) as homozygous mutation of TSPEAR gene.

Conclusion: Atypical genitalia is a novel association with ectodermal dysplasia which needs multidisciplinary team management including pediatric surgery, endocrinology, endodontics, dermatology and psychology.