Testicular function in active ankylosing spondylitis. Therapeutic response to human chorionic gonadotrophin.

Testicular function was studied in 22 patients with ankylosing spondylitis (AS) with serum measurements of hormone levels, seminal fluid analysis and testicular reserve test. Results were correlated with disease activity. The abnormal findings were elevated luteinizing hormone (LH), inversion of estradiol/testosterone ratio (E2:T) and diminished testicular reserve for testosterone (T) and slightly increased for estradiol (E2). Nine patients with severe active AS received biweekly 2,500 IU of human chorionic gonadotrophin injections with a resulting increase in E2 serum levels. When the values of E2 reached 40 pg/ml or higher, there was a decrease of the sedimentation rate (p less than 0.05) and a reversal to normal of the E2:T ratio. This was accompanied by an improvement in AS at the 10th week that lasted up to 9 weeks after discontinuation of treatment. Our findings suggest a possible role of sex hormones in the physiopathogenesis of AS and offers a possible therapeutic alternative.