title: Prepubertal diagnosis of X-linked congenital adrenal hypoplasia presenting after infancy.
abstract: X-linked congenital adrenal hypoplasia (CAH) presents classically with adrenal insufficiency within the first 6 months of life, as the fetal adrenal cortex progressively involutes. However, there is increasing recognition of delayed presentation after infancy with the need for accurate molecular diagnosis to avoid an erroneous diagnosis of other more common causes of adrenal insufficiency in childhood. We report our genetic studies of a pedigree with two affected boys presenting with late onset X-linked CAH, diagnosed by the presence of a known W171X mutation of the DAX-1 gene, in whom the mother was an obligate heterozygote. Unlike other causes of adrenal insufficiency, the significance of this diagnosis lies in the important association of hypogonadotropic hypogonadism, and the provision of accurate genetic counselling.
  
  
  CONCLUSIONS
  This study demonstrates that genetic analysis for X-linked congenital adrenal hypoplasia is essential to confirm the diagnosis in prepubertal patients presenting with adrenal insufficiency after infancy.
authors.affiliation: Department of Paediatrics, Faculty of Medicine, National University of Singapore, Singapore. paelky@nus.edu.sg
authors.forename: K Y
authors.initials: KY
authors.lastname: Loke
authors.forename: K S
authors.initials: KS
authors.lastname: Larry
authors.forename: Y S
authors.initials: YS
authors.lastname: Lee
authors.forename: M
authors.initials: M
authors.lastname: Peter
authors.forename: S L
authors.initials: SL
authors.lastname: Drop
mesh_terms: D000309:Adrenal Insufficiency / Q000151:congenital* / Q000235:genetics*; D000367:Age Factors; D002648:Child; D002675:Child, Preschool; D008040:Genetic Linkage; D006801:Humans; D008297:Male; D010375:Pedigree; D014960:X Chromosome