Evaluation of the CROMATEST rapid test for the detection of Chlamydia trachomatis

Abstract

Introduction: Chlamydia trachomatis (CT) infection is recognized as the most common bacterial sexually transmitted infection (STI). The World Health Organization reports approximately 131 million cases annually.

Objective: To evaluate the performance of the CROMATEST rapid test (Linear Chemicals. S.L. Barcelona España), using clinical samples.

Methods: A total of 72 individuals were studied (27 women and 7 men), and the same number of clinical samples. Of which, 38 vaginal swabs from adolescents with symptoms of STI from two pediatric hospitals from Havana, and 34 urine samples from apparently healthy volunteers, from the “Pedro Kourí” Institute of Tropical Medicine (IPK). The CROMATEST assay was applied to the samples and a commercial RT-PCR was used as reference test. Sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) were calculated.

Results: Of the samples under study, six were positive by the CROMATEST rapid test, while five were reactive for CT by mean of RT-PCR. One sample was only reactive by the reference test. Of the 66 negative samples, 65 were non-reactive by both tests; one sample was negative by RT-PCR and positive by CROMATEST. The percentage of agreement between both tests was 95 % and the Kappa value 0.8182. A sensitivity 83.33 %, specificity 98.48 %, PPV 83.33 % and NPV 98.48 %, were obtained.

Conclusion: The CROMATEST rapid test had an excellent performance when evaluated against the reference test; we recommend its use as a rapid test for the detection of CT.