New diagnostic test can detect Chlamydia trachomatis in less than 20 minutes
Researchers have developed a new assay for rapid and sensitive detection of Chlamydia trachomatis, the most common sexually transmitted infection (STI) in humans. This procedure takes less than 20 minutes and can be easily performed at the point of care (POC) during the patient’s visit.
C. trachomatis affects 5% to 10% of the population and is particularly common in young adults under 25 years. It is a major public health concern due to its prevalence and potential severe long-term consequences. One of the main reasons it is so prevalent is that in the majority of cases (75% of women and 50% of men) there are minimal to no symptoms, and it therefore often goes undiagnosed. Infection is associated with non-gonococcal urethritis in men and several inflammatory reproductive tract syndromes in women such as inflammation of the uterine cervix and pelvic inflammatory disease. Untreated, the infection increases the risk of ectopic pregnancy and is one of the leading causes of female infertility worldwide.
The assay uses recombinase polymerase amplification (RPA), a nucleic acid amplification technique (NAAT), to detect C. trachomatis directly from urine samples. Because the assay’s novel approach does not require the purification of total DNA from the urine sample, the need for specialized equipment is eliminated. The procedure is significantly less laborious, less time-consuming, and consequently less expensive. It is relatively simple to perform and could therefore be applied in numerous POC settings.
‘The assay enables highly specific C. trachomatis detection with sensitivity levels significantly improved compared to currently available C. trachomatis POC assays,’ says Ülo Langel, PhD, Professor of Molecular Biotechnology, University of Tartu, Estonia, and Professor of Neurochemistry,Stockholm University, Sweden.
Existing polymerase chain reaction (PCR)-based techniques for testing C. trachomatis are widely applied but are only suitable for use in hospitals with trained staff and expensive machinery. Studies have shown that up to 50% of patients never return to get the diagnostic result or required treatment.
Although several rapid-diagnosis POC tests have already been developed, none offer a comparable sensitivity to hospital-based techniques. Recent independent studies have shown that currently available POC tests have a sensitivity of just 10% to 40%. Initial analysis of the new assay’s performance indicated a specificity of 100% and a sensitivity of 83%, evidence of its potential reliability.
‘The alarmingly poor performance of the available POC tests for C. trachomatis has limited their wider use, and there is a clear requirement for more sensitive and cost-effective diagnostic platforms. Hence, the need for an applicable on-site test that offers reasonably sensitive detection,’ concludes Prof. Langel.
Elsevier
