A 28-year-old man comes to the physician for evaluation of infertility. He is healthy and has no other complaints. He eats a high-protein diet and exercises daily in order to be muscular. He weighs 85 kg (187 lb) and is 175 cm (5'8") tall. His temperature is 37.2° C (98.9° F) and blood pressure is 130/82 mm Hg. Physical examination shows small testes. The remainder of the examination shows no abnormalities. Initial laboratory studies show: Which of the following is the most likely cause of his infertility?

Question

A 28-year-old man comes to the physician for evaluation of infertility.  He is healthy and has no other complaints.  He eats a high-protein diet and exercises daily in order to be muscular.  He weighs 85 kg (187 lb) and is 175 cm (5'8") tall.  His temperature is 37.2° C (98.9° F) and blood pressure is 130/82 mm Hg.  Physical examination shows small testes.  The remainder of the examination shows no abnormalities.  Initial laboratory studies show:  Which of the following is the most likely cause of his infertility?

Quizplus · Accepted Answer

This patient presents for evaluation of infertility likely due to anabolic steroid (e.g., testosterone analog) abuse. Anabolic steroids are commonly used by many bodybuilders and athletes to enhance performance and muscle mass. Anabolic steroids contain exogenous androgens that inhibit GnRH release by the hypothalamus (due to feedback inhibition), which causes decreased LH and FSH release by the pituitary gland and leads to decreased sperm and testosterone production by the testes. The exogenous androgen suppresses native testosterone production but is detected as testosterone by current assays, so patients can have normal serum testosterone levels. Other adverse effects include acne, gynecomastia (due to conversion of the androgens to estrone), decreased testicular size, aggressiveness, and psychotic symptoms. Laboratory findings can show erythrocytosis (due to increased erythropoiesis) with elevated hemoglobin, cholestasis, hepatic failure, dyslipidemia, and slightly elevated creatinine (due to increased muscle mass). (Choice A) Klinefelter syndrome (i.e., XXY seminiferous tubule dysgenesis) is an inherited disorder characterized by testicular fibrosis (primary hypogonadism), azoospermia, gynecomastia, decreased intelligence, increased axial skeletal growth, and high FSH and LH levels. (Choice B) Mumps orchitis is a potential cause of infertility that is characterized by acute testicular pain and inflammation during the acute viral illness. (Choice D) Myotonic dystrophy is characterized by testicular atrophy as well as widespread muscular atrophy, weakness, lower-than-normal testosterone level, and high FSH and LH levels. (Choice E) Varicocele results in scrotal swelling, with a "bag of worms" sensation on palpation. (Choice F) Cryptorchidism manifests in infancy, with a failure to palpate two testes in the scrotum on examination. Patients are at an increased risk of testicular cancer. (Choice G) Testicular torsion produces acute testicular pain. (Choice H) Chronic medical illness typically results in anemia of chronic disease rather than erythrocytosis. Educational objective: Anabolic steroid use by a man can produce infertility by suppressing the production of GnRH, LH, and FSH. References: Anabolic steroids and semen parameters in bodybuilders (http://www.ncbi.nlm.nih.gov/pubmed/2512180)

A 28-Year-Old Man Comes to the Physician for Evaluation of Infertility