Gonadal dysfunction in men with chronic kidney disease: clinical features, prognostic implications and therapeutic options.

Gonadal dysfunction is a frequent finding in men with chronic kidney disease and with end-stage renal disease. Testosterone deficiency, usually accompanied by elevation of serum gonadotropin concentrations, is present in 26-66% of men with different degrees of renal failure. Uremia-associated hypogonadism is multifactorial in its origin, and rarely improves with initiation of dialysis, although it usually normalizes after renal transplantation. Experimental and clinical evidence suggests that testosterone may have important clinical implications with regards to kidney disease progression, derangements in sexual drive, libido and erectile dysfunction, development of anemia, impairment of muscle mass and strength, and also progression of atherosclerosis and cardiovascular disease. Additionally, low testosterone levels in hemodialysis patients have been associated with increased mortality risk in some studies. Currently, we count with available therapeutic options in the management of uremic hypogonadism, from optimal delivery of dialysis and adequate nutritional intake, to hormone replacement therapy with different testosterone preparations. Other potential options for treatment include the use of antiestrogens, dopamine agonists, erythropoiesis-stimulating factors, vitamins, essential trace elements, chorionic gonadotropin and renal transplantation. Potential adverse effects of androgen replacement therapy in patients with kidney disease comprise, however, erythrocytosis, prostate and breast cancer growth, reduced fertility, gynecomastia, obstructive sleep apnea and fluid retention. Androgen preparations should be used with caution with stringent monitoring in uremic men. Although there are encouraging data suggesting plausible benefits from testosterone replacement therapy, further studies are needed with regards to safety and effectiveness of this therapy.