Retesting and follow-up of first-catch urines from men yield variable results with three Chlamydia trachomatis nucleic acid amplification tests

First-catch urines from 276 asymptomatic male military recruits were screen ed by polymerase chain reaction for the detection of Chlamydia trachomatis. Eight initially positive specimens were retested by polymerase chain react ion, ligase chain reaction and transcription-mediated amplification. Urine specimens from six (2.2%) subjects were considered to contain C, trachomati s. However, retesting of serially collected urines from five of these six s ubjects using different nucleic acid amplification methods showed some disc repancy. This may have a major impact on the efficacy of screening programs for C. trachomatis in low prevalence populations.