Comparative Study of the Clinical Characteristics of Patients With Sexually Transmitted Infections Diagnosed by Nucleic Acid Amplification Tests.

BACKGROUND

Sexually transmitted infections (STIs) caused by Chlamydia trachomatis (CT), Mycoplasma genitalium (MG), and Neisseria gonorrhoeae (NG) are major public health concerns. While nucleic acid amplification tests (NAATs) are the primary diagnostic tool for these pathogens, research on pathogen-specific characteristics and risk factors for NAAT clearance failure remain limited in Korea. This study analyzed clinical features of STIs and post-treatment NAAT changes.

METHODS

This retrospective cohort study included adult, non-pregnant patients diagnosed with CT, MG, or NG via NAAT at a secondary care hospital between 2012 and 2024. Clinical characteristics were compared using the Kruskal-Wallis test, and multivariate logistic regression identified risk factors for NAAT clearance failure in patients with follow-up NAAT within three months.

RESULTS

Among 500 STI cases, 80.8% were female, with a median age of 27.0 years. CT was the most common pathogen (53.8%), followed by MG (37.2%) and NG (9.0%). CT infections had the highest complication rate (28.6%), while NG infections were more frequently symptomatic (77.8%) and associated with pyuria (46.4%). Of 221 patients with follow-up NAAT, 14.9% failed clearance. MG infection (adjusted odds ratio [aOR], 6.100; 95% confidence interval [CI], 2.711-13.725; P < 0.001) and symptomatic presentation (aOR, 2.542; 95% CI, 1.103-5.861; P = 0.029) were independent risk factors for clearance failure.

CONCLUSION

CT showed the highest complication rate and NG was the most symptomatic. MG was a key predictor of NAAT clearance failure, underscoring the need for antimicrobial resistance monitoring and optimized retreatment strategies.