Background: Chronic prostatitis has been a common disease reported with high frequency in ankylosing spondylitis (AS) even from decades ago. Infectious (Chlamydia trachomatis) or non-infectious (uric acid) prostatitis can hypothetically trigger vertebral inflammation in AS. This study aimed to assess the features of chronic prostatitis in patients with AS compared to healthy controls.
Methods: A cross-sectional study including male patients with AS and healthy controls who agreed to undergo a prostate examination was conducted. Structured clinical interviews, prostate physical examinations, and cytological, biochemical, and microbiological tests on urinary samples collected before and after standardized prostatic massage (pre- and post-massage test) were performed.
Results: Ninety participants (45 AS patients, mean age: 52.5 ± 10.0 years, with longstanding disease, 12.4 ± 6.9 years, and 45 controls, mean age: 52.8 ± 12.1 years) were included. National Institutes of Health - Chronic Prostatitis Symptom Index (NIH-CPSI) scores were similar in the AS and control groups (4.0 [1.0-12.0] vs. 5.0 [1.0-8.5], p = 0.994). The frequencies of symptoms of chronic prostatitis (NIH-CPSI Pain Domain ≥4) were also similar in both groups (23.3% vs. 22.7%, p = 0.953). Results of polymerase chain reaction tests for Chlamydia trachomatis were negative in all tested urinary samples, and uric acid concentrations and leukocyte counts were similar in all pre- and post-massage urinary samples.
Conclusions: In this study, chronic prostatitis occurred in male patients with AS, but its frequency and characteristics did not differ from those found in the healthy male population of similar age.
Keywords: Ankylosing spondylitis; Chlamydia trachomatis; Pelvic pain; Prostatitis; Uric acid.