Urethritis-associated Pathogens in Urine from Men with Non-gonococcal Urethritis: A Case-control Study

Area of Science:

• Microbiology
• Urology
• Infectious Diseases

Background:

• Non-gonococcal urethritis (NGU) etiology is unknown in 30-40% of patients.
• Identifying causative agents is crucial for effective treatment and prevention of NGU.
• Current diagnostic methods may not cover all potential pathogens.

Purpose of the Study:

• To investigate the etiological agents of NGU in Swedish men.
• To determine the association of specific pathogens with acute and chronic NGU.
• To identify factors contributing to unexplained NGU cases.

Main Methods:

• Quantitative PCR was used to detect Chlamydia trachomatis, Mycoplasma genitalium, Ureaplasma urealyticum, and other potential pathogens in urine samples.
• Case-control study design comparing men with acute/chronic NGU to controls without NGU.
• Multivariate analysis was employed to assess associations between pathogens and NGU.

Main Results:

• Chlamydia trachomatis, Mycoplasma genitalium, and Ureaplasma urealyticum were associated with NGU.
• Ureaplasma urealyticum, with bacterial loads ≥1.3 × 10^3 genome equivalents/ml, was significantly more prevalent in acute NGU cases (20%) than controls (11%).
• Viral and Haemophilus influenzae infections may explain a small proportion of NGU cases, leaving at least 24% of acute NGU cases unexplained.

Conclusions:

• Ureaplasma urealyticum is a significant etiological agent in acute NGU.
• A considerable percentage of NGU cases remain unexplained, necessitating further research into novel pathogens or contributing factors.
• Lifetime sexual partners number was inversely correlated with U. urealyticum bacterial load.