Alarmingly poor performance in Chlamydia trachomatis point-of-care testing

Abstract

Background Infection by Chlamydia trachomatis (CT) is the most prevalent sexually transmitted infection (STI) world wide. The most frequently used diagnostic test for CT is a nucleic acid amplification test (NAAT), which is highly sensitive and specific. To further shorten time delay until diagnosis has been made, in order to prevent CT spread, the use of point-of-care (POC) tests may be the way forward. Objectives The diagnostic performance of three POC tests, Handilab-C, Biorapid CHLAMYDIA Ag test and QuickVue Chlamydia test, was evaluated and compared with NAAT. Methods All women, above the age of 16 years, attending for a consultation at an STI clinic between September 2007 and April 2008, were asked to participate. Women were asked to complete a short questionnaire and to collect six self-taken vaginal swabs (SVS). SVS 2 was used for NAAT and SVS 3 to 5 were randomised for the different POC tests. SVS 1 and 6 were used for determining quantitative CT load to validate the use of successive SVS. All POC tests were performed without knowledge of NAAT results. NAAT was used as the 'gold standard'. Results 772 women were included. CT prevalence was 11% in our population. Sensitivities of the Biorapid CHLAMYDIA Ag test, QuickVue Chlamydia and Handilab-C test were 17%, 27% and 12%, respectively. Conclusions The evaluated POC tests, owing to their very low sensitivities, are not ready for widespread use. These results underline the need for good-quality assurance of POC tests, especially in view of the increased availability of these tests on the internet.

Analytical Evaluation of GeneXpert CT/NG, the First Genetic Point-of-Care Assay for Simultaneous Detection of Neisseria gonorrhoeae and Chlamydia trachomatis

“…In the past, POC tests have generally relied upon lateral flow technology, and most tests have demonstrated suboptimal performance (2,3). Cepheid GeneXpert CT/NG is a new Food and Drug Administration (FDA)-approved rapid molecular assay for simultaneous detection of N. gonorrhoeae and C. trachomatis.…”

Diagnosis and Management of UncomplicatedChlamydia trachomatisInfections in Adolescents and Adults: Summary of Evidence Reviewed for the 2015 Centers for Disease Control and Prevention Sexually Transmitted Diseases Treatment Guidelines

“…Sabidó et al evaluated the performance of the Chlamydia test card POC test on cervical swabs compared with CT PCR and found that with PCR as the reference standard, the Chlamydia test card had a sensitivity of 62.9% and specificity of 99.6% [59]. Van Dommelen et al evaluated the performance of 3 CT POC tests on vaginal swabs compared with CT PCR and found that with CT PCR as the reference standard, the sensitivities of the Handilab-C test, Biorapid CHLA-MYDIA Ag test, and QuickVue Chlamydia test were 12%, 17%, and 27%, respectively, whereas the specificities were 92%, 93.5%, and 99.7%, respectively [60]. Van der Helm et al evaluated the performance of the Chlamydia Rapid Test on vaginal swabs compared with CT TMA and found that with TMA as the reference standard, the Chlamydia Rapid Test had a sensitivity of 41.2% and specificity of 96.4%; they further stratified sensitivity by CT load and found that the sensitivity of the Chlamydia Rapid Test was 12.5% with a low CT load and 73.5% with a high CT load [61].…”

Evaluation of an enzymaticChlamydia trachomatispoint-of-care rapid assay in Rwanda: the BioChekSwab Rapid Test: Table 1

“…However, the BioChekSwab test, also known as the SELFCheck Chlamydia assay (EnZtek Diagnostics Incorporated, Rio Vista, California, USA), uses an enzyme substrate which, when hydrolysed by a CT-specific peptide hydrolase, produces fluorescence that can be read colorimetrically by adding a colour developing agent. One other test that detects the enzyme Peptidase 123A is available (the Handilab-C test, Zonda Inc, Dallas, Texas, USA), and its sensitivity was 12.5% and specificity was 93.5% 1 3…”