Real-World impact of multiplex PCR testing on antimicrobial management in patients evaluated for sexually transmitted infections

Abstract

To evaluate the impact of multiplex PCR results on antimicrobial management in patients undergoing evaluation for sexually transmitted infections (STIs), specifically focusing on treatment initiation, modification, or withholding following test results. METHODS: This retrospective single-center study included adult outpatients who underwent multiplex STI PCR testing at Gazi University Hospital between July 2019 and November 2022. Clinical and treatment data were reviewed, and the effect of PCR results on antimicrobial management was assessed using predefined clinical scenarios. RESULTS: A total of 731 patients were included, and PCR positivity was detected in 39.7% (290/731) of tests. The most frequently detected microorganisms were Ureaplasma parvum (18.1%), Ureaplasma urealyticum (14.9%), and Mycoplasma hominis (10%). Among asymptomatic patients with clinically significant pathogens, targeted antimicrobial therapy was initiated in 75% (30/40). Among asymptomatic patients with organisms of uncertain clinical significance, antimicrobial therapy was unnecessarily initiated in 43% (43/100). In symptomatic patients with clinically significant pathogens, empirical therapy was modified based on PCR results in 3 patients. Among symptomatic patients with negative PCR results, antimicrobial therapy was not initiated in 78.2% (169/216). Overall, PCR results were associated with management patterns potentially consistent with antimicrobial stewardship benefits in 202 patients. CONCLUSIONS: Multiplex PCR testing may contribute to antimicrobial management in STI evaluation by facilitating targeted therapy when clinically significant pathogens are detected. However, the role of negative PCR results in supporting decisions not to initiate antimicrobial treatment should be interpreted cautiously, particularly in patients with nonspecific symptoms. Broad multiplex panels may also promote overtreatment when microorganisms with uncertain clinical significance are detected.