title: Multiple forms of hypogonadism of central, peripheral or combined origin in males with Prader-Willi syndrome.
abstract: BACKGROUND
  Hypogonadism in Prader-Willi syndrome (PWS) is generally attributed to hypothalamic dysfunction or to primary gonadal defect, but pathophysiology is still unclear.
  
  
  OBJECTIVE
  To investigate the aetiology of hypothalamic-pituitary-gonadal axis dysfunction in PWS males.
  
  
  METHODS
  Clinical examination and blood sampling for luteinizing hormone (LH), follicle-stimulating hormone (FSH), testosterone, inhibin B and sexhormone-binding globulin (SHBG) were performed in 34 PWS patients, age 5·1-42·7 years, and in 125 healthy males of same age range. All participants were divided into two groups : < or ≥13·5 years.
  
  
  RESULTS
  Pubertal PWS patients showed an arrest of pubertal development. Patients <13·5 years had normal LH, FSH, testosterone and 7/10 had low inhibin B. Among those ≥13·5 years, 8/24 patients had normal LH and testosterone, high FSH and low inhibin B. 5/24 had low FSH, LH, testosterone and inhibin B; one showed normal LH and FSH despite low testosterone and inhibin B; 4/24 had low testosterone and LH but normal FSH despite low inhibin B; 6/24 showed high FSH, low inhibin B and normal LH despite low testosterone. Compared with controls, patients <13·5 years had lower LH, inhibin B, similar FSH, testosterone, SHBG levels and testicular volume; those ≥13·5 years had smaller testicular volume, near-significantly lower LH, testosterone, SHBG, inhibin B and higher FSH.
  
  
  CONCLUSIONS
  PWS patients display heterogeneity of hypogonadism: (i) hypogonadotropic hypogonadism of central origin for LH and/or FSH; (ii) early primary testicular dysfunction (Sertoli cells damage); and (iii) a combined hypogonadism (testicular origin for FSH-inhibin B axis and central origin for LH-T axis).
authors: Department of Experimental Medicine, Sapienza University of Rome, Italy.
authors: A F
authors: AF
authors: Radicioni
authors: G
authors: G
authors: Di Giorgio
authors: G
authors: G
authors: Grugni
authors: M
authors: M
authors: Cuttini
authors: V
authors: V
authors: Losacco
authors: A
authors: A
authors: Anzuini
authors: S
authors: S
authors: Spera
authors: C
authors: C
authors: Marzano
authors: A
authors: A
authors: Lenzi
authors: M
authors: M
authors: Cappa
authors: A
authors: A
authors: Crinò
mesh_terms: D000293:Adolescent; D000328:Adult; D002648:Child; D002675:Child, Preschool; D005640:Follicle Stimulating Hormone / Q000097:blood; D006801:Humans; D007006:Hypogonadism / Q000097:blood / Q000209:etiology*; D007265:Inhibins / Q000097:blood; D007986:Luteinizing Hormone / Q000097:blood; D008297:Male; D011218:Prader-Willi Syndrome / Q000097:blood / Q000150:complications* / Q000503:physiopathology; D011627:Puberty; D012738:Sex Hormone-Binding Globulin / Q000378:metabolism; D013739:Testosterone / Q000031:analogs & derivatives / Q000097:blood; D055815:Young Adult
chemical_list: D012738:Sex Hormone-Binding Globulin; D013739:Testosterone; D007265:Inhibins; C004648:testosterone enanthate; D007986:Luteinizing Hormone; D005640:Follicle Stimulating Hormone