RESUMO
BACKGROUND: Abnormalities of dihydrotestosterone conversion [5α-reductase deficiency: online Mendelian inheritance in man (OMIM) 607306] or actions of androgens [partial androgen insensitivity syndrome (PAIS): OMIM 312300] during the 8th-12th weeks of gestation cause varying degrees of undervirilized external genitalia in 46, XY disorders of sex development (DSD) with increased testosterone production. The objective of the study was to determine clinical and genetic characteristics of Thai patients with 46, XY DSD. METHODS: A cross-sectional study was conducted in 46, XY DSD with increased testosterone production (n=43) evaluated by a human chorionic gonadotropin (hCG) stimulation test or clinical features consistent with 5α-reductase deficiency or PAIS. PCR sequencing of the entire coding regions of the SRD5A2 and AR genes was performed. Molecular modeling analysis of the androgen receptor-ligand-binding domain (AR-LBD) of a novel mutation was constructed. RESULTS: Mutations were found in seven patients (16.3%): five (11.6%) and two (4.7%) patients had mutations in SRD5A2 and AR, respectively. Two novel mutations, SRD5A2 c.383A>G (p.Y128C) and AR c.2176C>T (p.R726C), were identified. Dimensional structural analysis of the novel mutated AR (p.R726C) revealed that it affected the co-activator binding [binding function-3 (BF-3)], not the testosterone binding site. Short phallus length was associated with 5α-reductase deficiency. CONCLUSIONS: Around 16.3% of our patients with 46, XY DSD had 5α-reductase deficiency or PAIS. Two novel mutations of SRD5A2 and AR were identified. The novel mutated AR (p.R726C) might affect the co-activator binding (BF-3), not the testosterone binding site.
Assuntos
3-Oxo-5-alfa-Esteroide 4-Desidrogenase/genética , Transtorno 46,XY do Desenvolvimento Sexual/genética , Transtorno 46,XY do Desenvolvimento Sexual/patologia , Proteínas de Membrana/genética , Mutação/genética , Receptores Androgênicos/genética , Sequência de Aminoácidos , Androgênios/metabolismo , Biomarcadores/metabolismo , Criança , Pré-Escolar , Estudos Transversais , Di-Hidrotestosterona/metabolismo , Transtorno 46,XY do Desenvolvimento Sexual/metabolismo , Feminino , Seguimentos , Humanos , Lactente , Masculino , Prognóstico , Conformação Proteica , Receptores Androgênicos/química , Homologia de Sequência de Aminoácidos , Testosterona/metabolismo , TailândiaRESUMO
Prolonged use of topical corticosteroids causes systemic adverse effects including Cushing's syndrome and hypothalamic-pituitary-adrenal (HPA) axis suppression, which is less common than that of the oral or parenteral route. At least 43 cases with iatrogenic Cushing syndrome from very potent topical steroid usage (Clobetasol) in children and adult have been published over the last 35 years particularly in developing countries. In children group (n = 22), most are infants with diaper dermatitis and two cases who had started topical application at a very early age and died from severe disseminated CMV infection. For the adult group (n = 21), the most common purpose of steroid use was for treatment of Psoriasis. The recovery period of HPA axis suppression was 3.49 ± 2.92 and 3.84 ± 2.51 months in children and adult, respectively. We report on an 8-month-old female infant who developed Cushing's syndrome and adrenal insufficiency after diaper dermatitis treatment through the misuse of Clobetasol without doctor's prescription. Physiologic dose of hydrocortisone was prescribed to prevent an adrenal crisis for 3 months and discontinued when HPA axis recovery was confirmed by normal morning cortisol and ACTH levels.
