ABSTRACT
The term "disorders of sex development" (DSD) includes congenital conditions in which development of chromosomal, gonadal or anatomical sex is atypical. Steroid 5-alpha reductase type 2 deficiency (5alpha-RD2) is an uncommon autosomal recessive disorder of sexual differentiation. It results from impaired conversion of testosterone (T) to dihydrotestosterone (DHT) due to mutations in the steroid 5-alpha reductase type 2 (SRD5A2) gene. It is characterized by a lack of masculinization in XY individuals due to failure to convert testosterone to dihydrotestosterone. More than 40 mutations have been reported in all five exons of the SRD5A2 gene. Here, we report on a 17-day-old Korean newborn who was confirmed to have 5alpha-RD2 by SRD5A2 gene analysis. He manifested micropenis, hypospadia and bilateral cryptorchidism without skin hyperpigmentation. T/DHT ratio after human chorionic gonadotropin (hCG) stimulation was slightly increased and genetic analysis of SRD5A2 revealed compound heterozygous mutations, c.657C > G (p.Phe219Leu) and c.656del (p.Phe219SerfsX60), the former of which is a novel mutation. We report a novel SRD5A2 gene mutation in a Korean newborn with 5alpha-RD2.
Subject(s)
Infant, Newborn , HumansABSTRACT
Children with abnormal sex development may present with ambiguous genitalia in the newborn period or lacking of secondary sexual characteristics in puberty. Clinicians should make a prompt and accurate diagnosis and counsel parents on therapeutic options to minimize or avoid medical and psychological complications. 5alpha-reductase deficiency is a rare autosomal recessive disorder of sex development caused by a mutation of the 5alpha-reductase type 2 gene. As a result, there is an abnormality in conversion of testosterone (T) to dihydrotestosterone (DHT) and children with 5alpha-reductase deficiency are born with ambiguous genitalia. Here, we report identical twins who presented with ambiguous genitalia with a 46,XY karyotype and were diagnosed as 5alpha-reductase deficiency.
Subject(s)
Child , Humans , Infant, Newborn , Dihydrotestosterone , Disorders of Sex Development , Karyotype , Parents , Puberty , Sexual Development , Testosterone , Twins, MonozygoticABSTRACT
5 alpha-reductase deficiency is a rare autosomal recessive disorder caused by mutations in the SRD5A2-gene, resulting in absent or diminished dihydrotestosterone (DHT) formation and, hence, in an underdevelopment of the external genitalia in patients with 46,XY karyotype. Recently we experienced a 17 years old patient with chief complaint of primary amenorrhea, who showed 46,XY karyotype, enlarged clitoris, virilization, undeveloped breast and palpable bilateral inguinal mass. We diagnosed it as 5 alpha?reductase deficiency and removed the bilateral gonads, so we report it with brief review of literature.
Subject(s)
Adolescent , Female , Humans , Disorder of Sex Development, 46,XY , Amenorrhea , Breast , Cholestenone 5 alpha-Reductase , Clitoris , Dihydrotestosterone , Genitalia , Gonads , Karyotype , VirilismABSTRACT
5 alpha-reductase deficiency resulting in male pseudohermaphroditism is a rare disease characterized by clitoral-like phallus, bifid scrotum, urogenital sinus, testis cited in labioscrotal folds. Evaluation of plasma T/DHT ratios in infancy, particularly after hCG stimulation of the testes and elevated urinary tetrahydrocortisol (THF) to 5 alpha-tetrahydrocortisol(5 alpha-THF) ratios provide a valuable dianostic test for 5 alpha-reductase deficiency. We report one case of 5 alpha-reductase deficiency who were presented with ambiguous genitalia and elevated T/DHT ratio before and after hCG stimulation.
Subject(s)
Disorder of Sex Development, 46,XY , Cholestenone 5 alpha-Reductase , Disorders of Sex Development , Plasma , Rare Diseases , Scrotum , Testis , TetrahydrocortisolABSTRACT
We evaluated 15 children with hypospadias or micropenis for the presence of 5 a-reductase deficiency. Serum testosterone and dihydrotestosterone(DHT) concentrations were measured before and 3 days after HCG stimulation. Also, testosterone : dihydrotestosterone (T:DHT) conversion ratios were calculated in each children in order to determine the activity of 5 a-reductase. DHT was abnormally low in 14 children, and T:DHT conversion ratios were abnormal in 12 children in basal state. But T:DHT conversion ratios were abnormal in 2 children after HCG stimulation. In children, 5 a-reductase deficiency can not be diagnosed low serum DHT or abnormal T:DHT conversion ratio, but diagnosed abnormally high T:DHT conversion ratio after HCG stimulation.