The case report demonstrates a case of a 31 years old patient referred to our outpatient endocrinology clinic for suspicion for central hypogonadism.
He had undergone a first line examination at a urology outpatient clinic for infertility. His semen analysis showed azoospermia, palpation of the testicles did nor reveal any abnormalities. Sex hormone levels were obtained where low gonadotropin (LH and FSH) levels with total testosterone level within normal range were noted.
Central hypogonadism as the possible reason for azoospermia and infertility was suspected.
On clinical examination the patient appeared well virilised, gynecomastia was not noticeable. Repeated blood samples confirmed low LH and FSH levels with total testosterone level close to the upper limit of the normal range. Free testosterone level was within normal range and so were the other pituitary hormones. Our conclusion was that the patient did not have central hypogonadism and that the low gonadotropins were a normal variant.
The patient was referred back to the urology outpatient clinic to search for the testicular reason for azoospermia. Ultrasound examination revealed a small tumor mass (1 cm in diameter) and high βHCG plasma levels were obtained. The patient underwent surgical removal of the right testicle. Histology revealed a seminoma of the testis.
LH and FSH levels increased slightly above the upper normal limit shortly after the surgery as the levels of HCG dropped. That is why we assume that paraneoplastic HCG acted as the dominant gonadotropin hormone in the patient and decreased the pituitary gonadotropin levels, while the testosterone level remained unchanged.
Conclusion: It is very important to consider testicular tumors in young patients with low LH and FSH levels, infertility and missing clinical sings of hypotestoteronemia.
Prague, Czech Republic
24 - 28 Apr 2010
European Society of Endocrinology