title: Testicular size development and reproductive hormones in boys and adult males with Noonan syndrome: a longitudinal study.
abstract: OBJECTIVE
  To characterise changes in testicular size and reproductive hormones and to investigate the aetiology of delayed puberty and impaired fertility in males with Noonan syndrome (NS).
  
  
  METHODS
  In this study, 12 males with NS were longitudinally followed from pre/early puberty until adulthood. Of the 12 males, ten had no medical history other than NS and were divided into two groups, undescended testes (UT), and descended testes (DT) and compared with a reference population.
  
  
  METHODS
  Hormone concentrations in serum were determined by immunoassays and testicular volume was measured using an orchidometer.
  
  
  RESULTS
  Before puberty, reproductive hormone levels were within the expected range in almost all cases. In some cases, LH, FSH and testosterone and oestradiol (E(2)) concentrations started to increase during puberty and inhibin B and anti-Müllerian hormone (AMH) declined to subnormal levels. Most of the boys studied had small testes that, in the majority of cases, progressed to normal size in adulthood. No difference in reproductive hormones was observed between the UT and DT groups either during puberty or at adulthood. However, as adults, males with NS had higher LH (5.7 vs 4.0 U/l, P<0.01), FSH (7.1 vs 2.5 U/l, P<0.001), testosterone (18.7 vs 15.6  nmol/l, P<0.01) and E(2) (66 vs 46  pmol/l, P<0.001) levels and lower AMH (33 vs 65  pmol/l, P<0.01) and inhibin B (median 108 vs 187  pg/ml, P<0.01) levels than the reference population.
  
  
  CONCLUSIONS
  In NS males, both Sertoli and Leydig cell dysfunction is common with reproductive hormone levels deteriorating progressively to adulthood.
authors.affiliation: Department of Pediatrics, Institute of Clinical Sciences, Göteborg Pediatric Growth Research Center, The Queen Silvia Children's Hospital, The Sahlgrenska Academy at University of Gothenborg, S-416 85 Göteborg, Sweden.
authors.forename: Carina
authors.initials: C
authors.lastname: Ankarberg-Lindgren
authors.forename: Otto
authors.initials: O
authors.lastname: Westphal
authors.forename: Jovanna
authors.initials: J
authors.lastname: Dahlgren
mesh_terms: D000293:Adolescent; D000328:Adult; D054304:Anti-Mullerian Hormone / Q000097:blood; D002648:Child; D003456:Cryptorchidism / Q000097:blood; D004958:Estradiol / Q000097:blood; D005640:Follicle Stimulating Hormone / Q000097:blood; D006801:Humans; D007265:Inhibins / Q000097:blood; D007985:Leydig Cells / Q000502:physiology; D008137:Longitudinal Studies; D007986:Luteinizing Hormone / Q000097:blood; D008297:Male; D009634:Noonan Syndrome / Q000503:physiopathology*; D011627:Puberty / Q000502:physiology; D012708:Sertoli Cells / Q000502:physiology; D013737:Testis / Q000254:growth & development*; D013739:Testosterone / Q000097:blood
chemical_list: C422364:inhibin B; D013739:Testosterone; D004958:Estradiol; D007265:Inhibins; D054304:Anti-Mullerian Hormone; D007986:Luteinizing Hormone; D005640:Follicle Stimulating Hormone