title: [Ligase chain reaction testing of pooled urine specimens to diagnose Chlamydia trachomatis infection].
abstract: OBJECTIVE
  The purpose of this study was to assess the utility and validity of pooling urine samples for molecular diagnosis of Chlamydia trachomatis infection.
  
  
  METHODS
  Of 1,220 urine samples collected from Mexican female and male adolescents, 305 pools were composed of fourth individual samples each, based on a calculation of optimal pool size. These were processed by ligase chain reaction (LCR) for the detection of C. trachomatis. Positive and gray-zone pools were reanalyzed individually. Cost savings were calculated comparing actual costs of testing to the cost that would have been incurred testing all 1,220 samples individually.
  
  
  RESULTS
  Pools results were: 56 positive, 19 gray-zones and 230 negative. Following individual retesting of positive and gray-zone pools, 59 cases of C. trachomatis infection were identified (4.8% prevalence). Thus, a total of 601 LCR tests were performed, for a 50.4% savings considering only the direct cost of the test.
  
  
  CONCLUSIONS
  Our experience shows that sample pooling is both a reliable and convenient tool for CT surveillance in our setting. It should be considered in other similar settings where limited resources constraint surveillance of STIs.
authors.affiliation: Centro de Investigación sobre Enfermedades Infecciosas, Cuba.
authors.forename: Miguel Angel
authors.initials: MA
authors.lastname: Sánchez-Alemán
authors.forename: Juan Pablo
authors.initials: JP
authors.lastname: Gutiérrez
authors.forename: Stefano Michael
authors.initials: SM
authors.lastname: Bertozzi
authors.forename: Maydelín
authors.initials: M
authors.lastname: Frontela-Noda
authors.forename: Victor
authors.initials: V
authors.lastname: Guerrero-Lemus
authors.forename: Carlos Jesús
authors.initials: CJ
authors.lastname: Conde-González
mesh_terms: D000293:Adolescent; D000328:Adult; D002690:Chlamydia Infections / Q000175:diagnosis* / Q000453:epidemiology / Q000382:microbiology / Q000652:urine; D002692:Chlamydia trachomatis / Q000302:isolation & purification*; D017046:Cost Savings; D003362:Cost-Benefit Analysis; D003365:Costs and Cost Analysis; D004269:DNA, Bacterial / Q000652:urine*; D005260:Female; D006801:Humans; D022521:Ligase Chain Reaction / Q000191:economics / Q000379:methods; D008297:Male; D008403:Mass Screening / Q000191:economics / Q000379:methods; D008800:Mexico / Q000453:epidemiology; D011159:Population Surveillance / Q000379:methods; D015995:Prevalence; D013048:Specimen Handling / Q000191:economics / Q000379:methods*; D014556:Urine / Q000382:microbiology*
chemical_list: D004269:DNA, Bacterial