title: Normal cortisol response on low-dose synacthen (1 microg) test in children with Prader Willi syndrome.
abstract: BACKGROUND
  It has been postulated that central adrenal insufficiency (CAI), resulting from hypothalamic dysfunction, may contribute to the increased unexplained death rates in Prader Willi syndrome (PWS). A study using the overnight metyrapone test reported a 60% prevalence of CAI in children with PWS. We used a low-dose Synacthen test to screen for CAI in children with PWS.
  
  
  METHODS
  We studied 41 children with genetic diagnosis of PWS [20 males; mean age, 7.68 (±5.23) yr] in five pediatric endocrinology centers in Australasia. All participants were randomly selected, and none had a history of Addisonian crisis. Ten of the cohort were receiving sex hormone therapy, 19 were receiving GH, and four were receiving T4. Their mean body mass index z-score was +1.48 (±1.68). Baseline morning ACTH and cortisol levels were measured, followed by iv administration of 1 μg Synacthen. Post-Synacthen cortisol levels were measured at 30 min, and a cortisol level above 500 nmol/liter was considered normal.
  
  
  RESULTS
  The mean baseline ACTH and cortisol were 15 (±14) ng/liter and 223 (±116) nmol/liter, respectively. The mean 30-min plasma cortisol was 690 (±114) nmol/liter, and the average increase from baseline was 201%.
  
  
  CONCLUSIONS
  Our result suggests that CAI is rare in children with PWS.
authors.affiliation: Department of Pediatric Endocrinology, Mater Children's Hospital, South Brisbane, Queensland 4101, Australia. ohn.nyunt@mater.org.au
authors.forename: Ohn
authors.initials: O
authors.lastname: Nyunt
authors.forename: Andrew M
authors.initials: AM
authors.lastname: Cotterill
authors.forename: Sinead M
authors.initials: SM
authors.lastname: Archbold
authors.forename: Joyce Y
authors.initials: JY
authors.lastname: Wu
authors.forename: Gary M
authors.initials: GM
authors.lastname: Leong
authors.forename: Charles F
authors.initials: CF
authors.lastname: Verge
authors.forename: Patricia A
authors.initials: PA
authors.lastname: Crock
authors.forename: Geoffrey R
authors.initials: GR
authors.lastname: Ambler
authors.forename: Paul
authors.initials: P
authors.lastname: Hofman
authors.forename: Mark
authors.initials: M
authors.lastname: Harris
mesh_terms: D000324:Adrenocorticotropic Hormone / Q000097:blood; D044362:Australasia; D015992:Body Mass Index; D002648:Child; D002675:Child, Preschool; D003366:Cosyntropin / Q000627:therapeutic use*; D005260:Female; D012739:Gonadal Steroid Hormones / Q000627:therapeutic use; D006728:Hormones / Q000627:therapeutic use; D006801:Humans; D006854:Hydrocortisone / Q000097:blood*; D008297:Male; D011218:Prader-Willi Syndrome / Q000097:blood / Q000188:drug therapy*; D012016:Reference Values; D013974:Thyroxine / Q000627:therapeutic use
chemical_list: D012739:Gonadal Steroid Hormones; D006728:Hormones; D003366:Cosyntropin; D000324:Adrenocorticotropic Hormone; D013974:Thyroxine; D006854:Hydrocortisone