Molecular Amplification Assays to Detect Chlamydial Infections in Urine Specimens from High School Female Students and to Monitor the Persistence of Chlamydial DNA after Therapy

Abstract

Polymerase chain reaction (PCR) and ligase chain reaction (LCR) were compared for the diagnosis of Chlamydia trachomatis infections by testing urine specimens from 408 high school female students. After therapy, sequential urine specimens were tested to determine persistence of chlamydial DNA in urine. Baseline PCR of cervical specimens was positive in 53 (13.0%) students, and PCR and LCR of urine specimens were positive in 63 (15.4%) and 60 (14.7%), respectively. After discrepant analysis, 64 (15.7%) patients could be confirmed as truly infected. Follow-up urine specimens from 33 infected patients demonstrated that at 1 -3 days after therapy, PCR and LCR were positive for 40% and 73.3%, respectively. Only at 15 days after therapy did all specimens test negative. Urine tests for Chlamydia organisms should not be used as a test of cure within 3 weeks after treatment. Use of urine assays for screening sexually active adolescents has the potential to significantly improve control of chlamydial infections. Joint Committee for Clinical Investigation of Johns Hopkins University were women, PCR is only approved for use with urine from men followed in the conduct of this study. The study was approved by the Institu-[10]. However, research has demonstrated that PCR is highly tional Review Boards of Johns Hopkins University and the Baltimore City Health Department. sensitive (87.8%) and specific (97.6%) when urine specimens Financial support: Region III Chlamydia Program (CDC); Roche Molecular from female subjects are used [16]. Because PCR and LCR Systems (Branchburg, NJ) and Abbott Laboratories (Abbott Park, IL) donated are so exquisitely sensitive and can detect DNA from nonviable test kits.

Duration of Persistence of Gonococcal DNA Detected by Ligase Chain Reaction in Men and Women following Recommended Therapy for Uncomplicated Gonorrhea

“…Similarly, detectable chlamydial nucleic acids were demonstrated in urine specimens tested by LCR and PCR for up to 2 weeks after adequate therapy in a population of female high school students. These findings are consistent with those from a smaller study of men and women who were treated with a single dose of azithromycin and who submitted urine specimens daily for testing for chlamydia by PCR and transcriptionmediated amplification (1,5). Collectively, these findings have led to the recommendation to refrain from using urine nucleic acid amplification tests for test of cure within the first 3 weeks following therapy for C. trachomatis (3).…”

“…Because of the exquisite sensitivity of nucleic acid amplification tests such as LCR, DNA from nonviable organisms could be detected following effective therapy, leading to a false-positive result and unnecessary additional treatment. This phenomenon has been reported in several studies evaluating the persistence of C. trachomatis nucleic acids by PCR or LCR following effective treatment (1,5,14). For instance, Workowski and colleagues (14) documented that 15% (3 of 20) of their female population continued to shed chlamydial DNA in cervical specimens for 1 week following completion of successful treatment with doxycycline.…”

“…Because nucleic acid amplification tests do not require living organisms for the detection of infection, concern has also been expressed about the potential for residual nucleic acids from nonviable organisms to persist in the genital tract, giving rise to false-positive test results if patients are retested too soon following successful therapy. Support for these concerns comes from studies demonstrating the persistence of Chlamydia trachomatis nucleic acids for periods as long as 2 to 3 weeks following therapy (1,5,14). No similar studies have been performed to describe the clearance of Neisseria gonorrhoeae nucleic acids from genital specimens following therapy.…”

Correlation between culture testing of swabs and ligase chain reaction of first void urine from patients recently treated for Chlamydia trachomatis

“…5 Other nucleic acid amplification (NAA) tests such as polymerase chain reaction (PCR) and transcription mediated amplification (TMA) have demonstrated similar efficacy on FVU and some data are available on the role of NAA assays as tests of cure. [6][7][8] …”

Evaluation of a Modified Sanitary Napkin as a Sample Self-Collection Device for the Detection of Genital Chlamydial Infection in Women

“…In a study, as many as 60% of chlamydia-infected adolescents would have been missed if the urine screening program had not been in place, because they refused the gynecologic examination (14). In addition, specimens may be collected in nontraditional medical settings, such as community centers and schools, and eventually at home (6,11,15,17). Although these methods have been shown to be relatively easy to use and sensitive for the detection of C. trachomatis, some women failed to collect adequate specimens or did not feel at ease with the technique (2,16,31).…”