title: Gonadal response after a single-dose stimulation test with recombinant human chorionic gonadotropin (rhCG) in patients with isolated prepubertal cryptorchidism.
abstract: BACKGROUND
  The evaluation of prepubertal gonadal Leydig cells secretion requires gonadotropin stimulation. Urinary hCG (human chorionic gonadotropin) is currently unavailable in many countries, however, recombinant hCG (rhCG) can be used. Our aim was to evaluate rhCG-stimulated testicular hormones in a group of patients with cryptorchidism.
  
  
  METHODS
  We evaluated 31 prepubertal boys (age range, 0.75-9.0 years) presenting with unilateral (n= 24) or bilateral (n= 7) cryptorchidism. Patients with other genital abnormalities, previous use of hCG or testosterone or previous surgeries were excluded. Blood samples were obtained at baseline and 7 days after a single subcutaneous dose of rhCG (Ovidrel® 250 mcg) to measure the testosterone, DHT (dihydrotestosterone), AMH (anti-Mullerian hormone), and inhibin B levels.
  
  
  RESULTS
  rhCG stimulation significantly increased testosterone levels from 10 ng/dl to 247.8 ± 135.8 ng/dl, increased DHT levels from 4.6 ± 0.8 to 32.3 ± 18.0 ng/dl, and increased the T/DHT ratio from 2.2 ± 0.4 to 8.0 ± 3.5. There was also a significant increase in inhibin B (from 105.8 ± 65.2 to 132.4 ± 56.1 pg/ml;p< 0.05) and AMH levels (from 109.4 ± 52.6 to 152.9 ± 65.2 ng/ml;p< 0.01) after the rhCG stimulation.
  
  
  CONCLUSIONS
  In this cohort, hormonal responses can be elicited after the rhCG stimulation test, suggesting that rhCG is a promising stimulation test to replace the urinary hCG test during the evaluation of gonadal Leydig cells function. The clinical applicability and adequate performance of rhCG testing must be investigated in future studies.
authors: Pediatric Endocrinology Unit, Pediatrics Department, Irmandade da Santa Casa de Misericórdia de São Paulo, and Santa Casa de São Paulo School of Medical Sciences, Rua Dr. Cesário Mota Jr, 112, Vila Buarque, São Paulo, CEP 01221-020 Brazil.
authors: Leticia Ribeiro
authors: LR
authors: Oliveira
authors: Pediatric Endocrinology Unit, Pediatrics Department, Irmandade da Santa Casa de Misericórdia de São Paulo, and Santa Casa de São Paulo School of Medical Sciences, Rua Dr. Cesário Mota Jr, 112, Vila Buarque, São Paulo, CEP 01221-020 Brazil.
authors: Thais Kataoka
authors: TK
authors: Homma
authors: Developmental Endocrinology Unit, University of São Paulo Faculty of Medicine Clinics Hospital - USP, São Paulo, Brazil.
authors: Renata Reis
authors: RR
authors: Woloszynek
authors: Developmental Endocrinology Unit, University of São Paulo Faculty of Medicine Clinics Hospital - USP, São Paulo, Brazil.
authors: Vinícius Nahime
authors: VN
authors: Brito
authors: Pediatric Endocrinology Unit, Pediatrics Department, Irmandade da Santa Casa de Misericórdia de São Paulo, and Santa Casa de São Paulo School of Medical Sciences, Rua Dr. Cesário Mota Jr, 112, Vila Buarque, São Paulo, CEP 01221-020 Brazil.
authors: Carlos Alberto
authors: CA
authors: Longui
keywords: Anti-Mullerian hormone; Cryptorchidism; Human Chorionic Gonadotropin; Recombinant hCG; Testosterone