Performance of antigen-based rapid test for Chlamydia trachomatis in comparison with polymerase chain reaction test

Background

Rapid tests for diagnosing Chlamydia trachomatis infection can facilitate patient treatment and reduce transmission, as patients can receive treatment during the same visit. This study aims to evaluate the performance of the rapid test compared to the PCR test for diagnosing C. trachomatis infection to assess its clinical applicability.

Methods

A cross-sectional study was conducted on participants aged > 18 years with symptoms of genital discharge. The performance of the rapid test was evaluated using the PCR test as the gold-standard.

Results

A total of 196 eligible patients were selected for the study. Females accounted for 68.4%, and those aged over 25 years represented 73.0% of the total. The prevalence of C. trachomatis infection was 14.3%. The overall return rate was 41.8%. The Chlamydia rapid test demonstrated a sensitivity of 53.6% (95% CI: 46.6–60.5%), specificity of 86.3% (95% CI: 81.5–91.1%), positive-predictive value of 39.5% (95% CI: 32.6–46.3%), and negative-predictive value of 91.8% (95% CI: 87.9–95.6%). The sensitivity of the rapid test was significantly higher in females, ≥ 25 years, those with past STIs, and symptoms including pruritus, dysuria, and purulent discharge than their counterparts (p < .05).

Conclusion

While the Chlamydia rapid test is less sensitive than the PCR test, it is easy to implement, cost-effective, provides quick results, and allows more patients to receive treatment during the same visit compared to the PCR test. The rapid test still holds value in managing C. trachomatis infection in resource-limited settings, particularly with a low return rate.