title: Baseline follicle-stimulating hormone is a strong predictor for the outcome of the gonadotrophin-releasing hormone test in young men with unilateral medium- or high-grade varicocele.
abstract: OBJECTIVE
  To investigate whether the gonadotrophin-releasing hormone (GnRH) test is an adequate diagnostic tool to identify testicular dysfunction in men with strictly unilateral varicocele and defined testicular volume; and to identify any peripheral venous variable which would predict the result of the GnRH test.
  
  
  METHODS
  In all, 102 GnRH tests were done in men with a left-sided varicocele. Follicle-stimulating hormone (FSH) and luteinizing hormone (LH) levels were determined. After intravenous administration of 100 microg GnRH, stimulated LH and FSH levels were measured. FSH levels of >8.2 U/L and LH levels of >51.7 U/L were considered exaggerated.
  
  
  RESULTS
  In all, 50 men had an exaggerated GnRH test result; all had an exaggerated FSH response and six also had an elevated LH response. The baseline FSH levels were higher (P < 0.001) and the testicular volume was smaller (P < 0.01) in men with an exaggerated GnRH test response. All men with a baseline FSH level of >5.6 U/L had an exaggerated GnRH test response.
  
  
  CONCLUSIONS
  A baseline FSH level of >5.6 U/L is a good predictor of the GnRH test outcome. Leydig cell function seems mainly undisturbed.
authors.affiliation: Department of Urology, Asklepios Clinic Barmbek, Hamburg, Germany. thorsten.bach@hansenet.de
authors.forename: Thorsten
authors.initials: T
authors.lastname: Bach
authors.forename: Dietrich
authors.initials: D
authors.lastname: Pfeiffer
authors.forename: Roland
authors.initials: R
authors.lastname: Tauber
mesh_terms: D000293:Adolescent; D000328:Adult; D005640:Follicle Stimulating Hormone / Q000097:blood*; D007987:Gonadotropin-Releasing Hormone; D006801:Humans; D007248:Infertility, Male / Q000097:blood / Q000209:etiology*; D007985:Leydig Cells / Q000502:physiology; D007986:Luteinizing Hormone / Q000097:blood; D008297:Male; D013733:Testicular Diseases / Q000097:blood / Q000175:diagnosis*; D014646:Varicocele / Q000175:diagnosis*
chemical_list: D007987:Gonadotropin-Releasing Hormone; D007986:Luteinizing Hormone; D005640:Follicle Stimulating Hormone