title: Highly sensitive and novel point-of-care system, aQcare Chlamydia TRF kit for detecting Chlamydia trachomatis by using europium (Eu) (III) chelated nanoparticles.
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.
authors.affiliation: Department of Laboratory Medicine, Kyungpook National University Hospital, Daegu, Korea.
authors.forename: Ji Yeon
authors.initials: JY
authors.lastname: Ham
authors.affiliation: Medisensor Inc., Daegu, Korea.
authors.forename: Jaean
authors.initials: J
authors.lastname: Jung
authors.affiliation: Medisensor Inc., Daegu, Korea.
authors.forename: Byung-Gap
authors.initials: BG
authors.lastname: Hwang
authors.affiliation: Medisensor Inc., Daegu, Korea.
authors.forename: Won-Jung
authors.initials: WJ
authors.lastname: Kim
authors.affiliation: Medisensor Inc., Daegu, Korea.
authors.forename: Young-Seop
authors.initials: YS
authors.lastname: Kim
authors.affiliation: Medisensor Inc., Daegu, Korea.
authors.forename: Eun-Ju
authors.initials: EJ
authors.lastname: Kim
authors.affiliation: Medisensor Inc., Daegu, Korea.
authors.forename: Mi-Yeon
authors.initials: MY
authors.lastname: Cho
authors.affiliation: Medisensor Inc., Daegu, Korea.
authors.forename: Mi-Sun
authors.initials: MS
authors.lastname: Hwang
authors.affiliation: Department of Laboratory Medicine, Kyungpook National University Hospital, Daegu, Korea. ; Department of Clinical Pathology, Kyungpook National University School of Medicine, Daegu, Korea.
authors.forename: Dong Il
authors.initials: DI
authors.lastname: Won
authors.affiliation: Department of Laboratory Medicine, Kyungpook National University Hospital, Daegu, Korea. ; Department of Clinical Pathology, Kyungpook National University School of Medicine, Daegu, Korea.
authors.forename: Jang Soo
authors.initials: JS
authors.lastname: Suh
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002690:Chlamydia Infections / Q000175:diagnosis*; D002692:Chlamydia trachomatis / Q000235:genetics* / Q000302:isolation & purification; D004269:DNA, Bacterial / Q000737:chemistry / Q000378:metabolism; D005063:Europium / Q000737:chemistry*; D005260:Female; D006801:Humans; D008297:Male; D053768:Metal Nanoparticles / Q000737:chemistry*; D008875:Middle Aged; D019095:Point-of-Care Systems; D011933:Reagent Kits, Diagnostic; D060888:Real-Time Polymerase Chain Reaction; D012680:Sensitivity and Specificity; D055815:Young Adult
chemical_list: D004269:DNA, Bacterial; D011933:Reagent Kits, Diagnostic; D005063:Europium
keywords: Chlamydia trachomatis; Europium; Point-of-care systems