Difficulties in diagnosis and treatment of 5alpha-reductase type 2 deficiency in a newborn with 46,XY DSD.
Horm Res Paediatr
; 74(1): 67-71, 2010.
Article
en En
| MEDLINE
| ID: mdl-20395661
BACKGROUND/AIMS: Steroid 5alpha-reductase deficiency (MIM*607306) caused by mutations in the SRD5A2 gene is characterized by a predominantly female phenotype at birth and significant virilization at puberty. The undermasculinization at birth results from low dihydrotestosterone (DHT) levels during fetal development as the type 2 isoenzyme activity is reduced. In puberty, when the type 1 isoenzyme activity increases, significant virilization occurs. Most 46,XY individuals with 5alpha-reductase 2 deficiency develop a male gender identity. CASE REPORT AND RESULTS: We present a case with a predominantly female phenotype and ambiguous external genitalia but a normal 46,XY karyotype. Plasma steroid analysis after beta-hCG stimulation at 8 days of age revealed a steroid profile estimated as normal with a testosterone (T)/DHT ratio of 9.5 initially misleading to the exclusion of 5alpha-reductase deficiency. However, mutation analysis of the SRD5A2 gene revealed a homozygote point mutation (Leu55Gln) confirming the diagnosis of 5alpha-reductase deficiency. A male phenotype was successfully achieved by hormone treatment with T and DHT after diagnosing 5alpha-reductase deficiency and a masculinization operation. As a side effect skeletal age accelerated temporarily. CONCLUSION: In individuals with predominantly female phenotype and suspected 5alpha-reductase deficiency, a T/DHT ratio during the neonatal period >8.5 might point to 5alpha-reductase deficiency. After confirmation of the diagnosis by molecular analysis of the SRD5A2 gene, a satisfactory change to a male phenotype can be achieved by hormone treatment preceding surgery.
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Dihidrotestosterona
/
Testosterona
/
3-Oxo-5-alfa-Esteroide 4-Deshidrogenasa
/
Disgenesia Gonadal 46 XY
Tipo de estudio:
Diagnostic_studies
Límite:
Female
/
Humans
/
Male
/
Newborn
Idioma:
En
Revista:
Horm Res Paediatr
Asunto de la revista:
ENDOCRINOLOGIA
/
PEDIATRIA
Año:
2010
Tipo del documento:
Article
País de afiliación:
Alemania
Pais de publicación:
Suiza