title: [Development of a gap ligase chain reaction for detection of Chlamydia trachomatis in newborn infants].
abstract: OBJECTIVE
  To establish a gap ligase chain reaction (G-LCR) assay for the detection of Chlamydia trachomatis (Ct) in neonates with pneumonia.
  
  
  METHODS
  A G-LCR DNA amplification assay that targeted the outer major membrane protein gene (omp1) of Ct was developed to detect Ct. The sensitivity and specificity of the G-LCR test was examined by the use of highly purified elementary bodies (EBs). Nasopharyngeal swabs taken from 328 neonates with pneumonia were analyzed by Gap-LCR and cell culture.
  
  
  RESULTS
  The detection limit of G-LCR was 2 EBs. G-LCR could detect five species of Ct and was not cross-reacted with C psittaci and other bacteria. The prevalence of Ct in 328 neonates with pneumonia, using an expanded gold standard of a positive cell culture or two confirmed positive non-culture tests, was 21% (69/328). After analysis of discrepant results, the sensitivity, specificity, and positive and negative predictive values for the G-LCR were 98.6%, 100%, 100% and 99.6%, respectively; whereas those for culture were 86.9%, 100%, 100% and 96.6%, respectively.
  
  
  CONCLUSIONS
  This study demonstrated that the G-LCR was a highly sensitive nonculture technique and good alternative test for the detection of chlamydial infections.
authors.affiliation: Department of Neonatology, Children's Hospital, Chongqing University of Medical Science, Chongqing 400014, China.
authors.forename: Hong
authors.initials: H
authors.lastname: Wei
authors.forename: Shi-xiao
authors.initials: SX
authors.lastname: Wu
authors.forename: Jia-lin
authors.initials: JL
authors.lastname: Yu
authors.forename: Jun
authors.initials: J
authors.lastname: Yang
authors.forename: Guan-xin
authors.initials: GX
authors.lastname: Liu
mesh_terms: D002690:Chlamydia Infections / Q000175:diagnosis / Q000382:microbiology; D002692:Chlamydia trachomatis / Q000235:genetics*; D005260:Female; D006801:Humans; D007231:Infant, Newborn; D022521:Ligase Chain Reaction / Q000379:methods*; D008297:Male; D012680:Sensitivity and Specificity