Antibodies to Chlamydia trachomatis heat-shock protein 60 kDa and detection of Mycoplasma genitalium and Ureaplasma urealyticum are associated independently with chronic nongonococcal urethritis

Background: Chronic nongonococcal urethritis (NGU) is a well-recognized clinical problem in genitourinary medicine clinics, but its etiology and optimal management are poorly understood. Goal: The authors showed previously that antibody to chlamydial hsp60 is associated with urethritis 30 to 92 days after treatment of acute NGU (chronic NGU) and that the detection of ureaplasmas or Mycoplasma genitalium is associated with chronic NGU in which symptoms or signs are present. The aim was to determine whether these associations are independent of each other. Study Design: This was a longitudinal prospective follow-up study over a 3-month period of 86 men with acute NGU. Men were tested for Chlamydia trachomatis, Mycoplasma genitalium, ureaplasmas, and antibody to chlamydia hsp60 at presentation and during follow-up. Results: The detection of either ureaplasmas or M genitalium (OR, 29.45; 95% CI, 1.78-487) and the occurrence of hsp60 antibody at 30 to 92 days' follow-up (OR, 26.45; 95% CI, 1.34-523) were associated independently with the development of chronic NGU 30 to 92 days after treatment of acute NGU. The presence of chlamydial hsp60 antibody at 30 to 92 days was not associated with the development of chronic NGU in which symptoms or signs were present (P = 0.363). Chlamydial hsp60 antibody was associated, however, with chronic NGU in which there were no symptoms or signs (P = 0.01). Conclusion: The results suggest that the immune response to chlamydial hsp60 may have a role in the etiology of chronic NGU in asymptomatic men who have no discharge on examination. The clinical relevance of this is unknown.