Ann Lab Med.  2015 Jan;35(1):50-56. 10.3343/alm.2015.35.1.50.

Highly Sensitive and Novel Point-of-Care System, aQcare Chlamydia TRF Kit for Detecting Chlamydia trachomatis by Using Europium (Eu) (III) Chelated Nanoparticles

• Ham JY
• Jung J
• Hwang BG
• Kim WJ
• Kim YS
• Kim EJ
• Cho MY
• Hwang MS
• Won DI
• Suh JS

• KMID: 2363147
• DOI: http://doi.org/10.3343/alm.2015.35.1.50

Abstract

BACKGROUND
The bacterium Chlamydia trachomatis is one of the leading causes of sexually transmitted diseases worldwide. Since no simple and effective tool exists to diagnose C. trachomatis infections, we evaluated a novel point-of-care (POC) test, aQcare Chlamydia TRF kit, which uses europium-chelated nanoparticles and a time-resolved fluorescence reader.
METHODS
The test performance was evaluated by comparing the results obtained using the novel POC testing kit with those obtained using a nucleic acid amplification test (NAAT), using 114 NAAT-positive and 327 NAAT-negative samples.
RESULTS
The cut-off value of the novel test was 20.8 with a detection limit of 0.27 ng/mL. No interference or cross-reactivity was observed. Diagnostic accuracy showed an overall sensitivity of 93.0% (106/114), specificity of 96.3% (315/327), positive predictive value (PPV) of 89.8% (106/118), and negative predictive value (NPV) of 97.5% (315/323). The sensitivity of the novel test was much higher than that of currently available POC tests. Furthermore, the relative ease and short turnaround time (30 min) of this assay enables C. trachomatis-infected individuals to be treated without a diagnostic delay.
CONCLUSIONS
This simple and novel test is a potential tool to screen a larger population, especially those in areas with limited resources.

Keyword

Chlamydia trachomatis; Europium; Point-of-care systems

MeSH Terms

Adult
Aged
Aged, 80 and over
Chlamydia Infections/*diagnosis
Chlamydia trachomatis/*genetics/isolation & purification
DNA, Bacterial/chemistry/metabolism
Europium/*chemistry
Female
Humans
Male
Metal Nanoparticles/*chemistry
Middle Aged
Point-of-Care Systems
Reagent Kits, Diagnostic
Real-Time Polymerase Chain Reaction
Sensitivity and Specificity
Young Adult
DNA, Bacterial
Europium
Reagent Kits, Diagnostic

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