Roles of Ureaplasma Species in Idiopathic Chronic Prostatitis: A Case-Control Study

PURPOSE: Because of the inconsistent symptoms associated with Ureaplasma infections, their clinical significances in genitourinary tracts are under debate. Therefore, we evaluated the presence of Ureaplasma urealyticum (UU) and Ureaplasma parvum (UP) in urine samples and examined their associations with chronic prostatitis (CP) through a case and control study. MATERIALS AND METHODS: We included 696 nonchlamydial nongonococcal (NCNG) urine samples from men; 350 were categorized into non-inflammatory CP, 88 in inflammatory CP, and 258 in non-CP group. We amplified a region in the Ureaplasma urease areas from these samples and determined their biovars using the Sanger method. RESULTS: Among the NCNG population, the rates of UU, UP, and non-UU/UP were 3.88%, 6.46%, and 89.66%, respectively. The overall infection rates of non-CP, inflammatory CP, and non-inflammatory CP groups were 4.15%, 6.10%, and 3.65% in UU (p=0.612) and 6.85%, 7.22%, and 6.50% in UP (p=0.968), respectively. UU infection increased the risk of white blood cell (WBC) counts (≥5) in urine (p=0.005). In contrast, UP infections did not increase the risks of urethritis. Re-analysis from the 633 men who were excluded from urethritis effects did not reveal the associations between UU infection and the clinical characteristics of CP. Furthermore, the profiles from the National Institutes of Health-Chronic Prostatitis Symptom Index questionnaire and WBC counts in expressed prostatic secretion were similar among the non-CP and the two CP groups in each Ureaplasma infection. CONCLUSIONS: We found that UU may induce male urethritis. However, Ureapalsma species in urine were not definitively associated with the occurrence of CP.