title: Setting the Gray Zone of Near-Cutoff Values in a Real-Time PCR Test for the Detection of Mycobacterium tuberculosis in an Intermediate Burden Country.
abstract: BACKGROUND
  Recently, molecular detection of Mycobacterium tuberculosis in a respiratory specimens is accepted as one of the standard procedures for diagnosis of tuberculosis in Korea. When detecting tuberculosis using a real-time polymerase chain reaction (PCR), results showed the repeated near-cutoff values in a specimen make it difficult for the laboratory to give definitive reports as positive or negative.
  
  
  METHODS
  We retrospectively evaluated clinical state of ninety-eight patients who were not currently taking antituberculosis medications and had near-cutoff values of respiratory specimens using a real-time PCR test.
  
  
  RESULTS
  Sixty-eight percent of the patients had clinical tuberculosis. In subgroup analysis, patients less than the age of 50, 94.3% had tuberculosis while only 55.6% of the patients with the age of equal and over 50 had tuberculosis (p < 0.001).
  
  
  CONCLUSIONS
  Setting a gray zone for real-time PCR result and give additional tailored information onto the interpretative report would be suggested for the clinical practice in an intermediate burden of tuberculosis country.
authors: Sung Kuk
authors: SK
authors: Hong
authors: Sue
authors: S
authors: Shin
authors: Jong-Hyun
authors: JH
authors: Yoon
authors: Eui-Chong
authors: EC
authors: Kim
mesh_terms: D001431:Bacteriological Techniques; D001992:Bronchoalveolar Lavage Fluid / Q000382:microbiology; D004269:DNA, Bacterial / Q000235:genetics*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009169:Mycobacterium tuberculosis / Q000235:genetics*; D011237:Predictive Value of Tests; D060888:Real-Time Polymerase Chain Reaction; D015203:Reproducibility of Results; D056910:Republic of Korea / Q000453:epidemiology; D012189:Retrospective Studies; D013183:Sputum / Q000382:microbiology; D014397:Tuberculosis, Pulmonary / Q000175:diagnosis* / Q000453:epidemiology / Q000382:microbiology
chemical_list: D004269:DNA, Bacterial