title: A diminished postnatal surge of Ad spermatogonia in cryptorchid infants is additional evidence for hypogonadotropic hypogonadism.
abstract: BACKGROUND
  The aim of this study was to describe the development of Ad spermatogonia in both unilateral and bilateral cryptorchid infants compared to a control population of comparable age and to note particularly the fate of Ad spermatogonia during the normal surge of testosterone and gonadotropin.
  
  
  METHODS
  The incidence and development of Ad (dark) adult type of spermatogonia were assessed in 270 testicular biopsies from 159 cryptorchid infants at 1-12 months of age. These results were compared to the control population of the same age.
  
  
  RESULTS
  The number of Ad spermatogonia increased markedly after five months of life in the control population. The scrotal testes of unilateral cryptorchid infants also had an increase in the number of Ad spermatogonia but it was distinctly lower than that of the control population. In contrast, this surge was completely absent in the cryptorchid testes. The number of Ad spermatogonia in unilateral cryptorchid testes correlated in a nonlinear fashion with those in the contralateral scrotal testes. The total number of germ cells in the cryptorchid testes in the first six months of life is normal, after which time it declines rapidly.
  
  
  CONCLUSIONS
  The impaired transformation of germ cells into Ad spermatogonia in both unilateral and bilateral cryptorchid infant testes during mini-puberty underscores the importance of hypogonadotropic-hypogonadism in the pathogenesis of this disease.
authors.affiliation: Kindertagesklinik, Liestal, Switzerland. ktk@kindertagesklinik.ch
authors.forename: Faruk
authors.initials: F
authors.lastname: Hadziselimovic
authors.forename: Lyman R
authors.initials: LR
authors.lastname: Emmons
authors.forename: Mauro W
authors.initials: MW
authors.lastname: Buser
mesh_terms: D001707:Biopsy, Needle; D016022:Case-Control Studies; D003456:Cryptorchidism / Q000150:complications* / Q000473:pathology* / Q000601:surgery; D005500:Follow-Up Studies; D006062:Gonadotropins / Q000378:metabolism; D006801:Humans; D007006:Hypogonadism / Q000209:etiology* / Q000503:physiopathology; D007150:Immunohistochemistry; D007223:Infant; D007231:Infant, Newborn; D007248:Infertility, Male / Q000517:prevention & control; D008297:Male; D011336:Probability; D012016:Reference Values; D018570:Risk Assessment; D013091:Spermatogenesis; D013093:Spermatogonia / Q000166:cytology*; D018709:Statistics, Nonparametric; D013557:Switzerland; D013739:Testosterone / Q000378:metabolism
chemical_list: D006062:Gonadotropins; D013739:Testosterone