Reasons for testing women for genital Chlamydia trachomatis infection in the Calgary region

OBJECTIVE: To determine the clinical reason(s) for screening women with varying degrees of risk for genital Chlamydia trachomatis (CT) in the Calgary region. DESIGN:Women aged 15 to 75 years were enrolled at various patient care locations.Pertinent risk factors for genital CT infection were recorded and a gynecological examination was performed.Two endocervical swabs and a first-void urine sample were collected for CT detection using two different nucleic acid amplification test methods. SETTING:Calgary is an urban region that provides healthcare services to a population of almost one million people.Microbiology services are provided by Calgary Laboratory Services through a centralized regional laboratory service. MAIN RESULTS:504 women with a mean age of 28.1 ± SD 8.22 years were enrolled.Two hundred ninety-one women (57.8%) were at high risk for acquiring genital CT infection.Twenty-eight (5.6%) tested positive for CT infection and almost all of these women (26 of 28, 93%) had risk factors for acquiring infection.Of the high-risk women, 9.8% were CT positive versus only 1.3% of women at low risk (P=0.0001).Only two of 152 (1.3%) women older than 30 years had genital CT infections.Although most women were asymptomatic, those with laboratory-confirmed CT infection were more likely to have genitourinary symptoms.Three hundred forty-three of 476 (72%) women who did not have genital CT infection had no risk factors, and screening was done as part of a routine gynecological examination for other purposes (prenatal visit, Pap smear). CONCLUSION:Women without risk factors are being screened routinely for genital CT infection as part of a routine gynecological examination done for other reasons.Elimination of the routine screening of low-risk women older than 30 years of age would decrease the current regional utilization of CT tests by as much as one-third.