Improving the Diagnosis and Linkage to Care of Chlamydia and Gonorrhea Infection in Prenatal Females in Edmonton, Alberta

• Author / Creator

  Walsh, Taylor

• Chlamydia and gonorrhea (CTNG) are sexually transmitted infections (STIs) that can lead to complications in males and females. If a pregnant individual is infected with CTNG, they risk passing the infection to their newborn through vertical transmission during delivery, which can lead to newborn pneumonia or ophthalmia neonatorum, potentially resulting in blindness. To prevent vertical transmission to the infant, in 2018, the Alberta government updated prenatal screening guidelines to include universal CTNG screening during the first trimester of pregnancy and an additional third-trimester screen for those at high risk for infection. This screening process depends on physicians' awareness of CTNG prenatal guidelines and knowledge of patients' lifestyles, which may not capture all females at risk for infection.
  Additionally, antimicrobial susceptibility testing (AST) is routinely conducted on positive NG isolates throughout Alberta to determine strains with antimicrobial resistance (AMR). Up-to-date AST results are essential to ensure that the most effective treatment is available for strains present in the province.
  This thesis investigates provincial AST results from 2016 to 2022, CTNG prenatal screening proportions from 2019 to 2022, and results from the establishment of a pilot “at delivery” universal screening program.
  To develop an antibiogram of Alberta’s NG isolates, AST results were collected for six antimicrobials: penicillin, tetracycline, ciprofloxacin, azithromycin, cefixime, and ceftriaxone, between the years 2016 and 2022, along with individual demographic data. The lowest susceptibilities were observed in penicillin, followed by ciprofloxacin and tetracycline. As of 2022, susceptibility rates were 100% for ceftriaxone and cefixime, followed by azithromycin (99%), tetracycline (34%), ciprofloxacin (27%), and penicillin (7%). Higher frequencies of strains non-susceptible to penicillin, ciprofloxacin, tetracycline, or azithromycin were found in individuals from higher income quintiles. The frequency of strains with azithromycin non-susceptibility was also higher in individuals from Edmonton health zones (51.90%, p=0.001).
  To determine guideline adherence for first-trimester screening, a retrospective analysis of laboratory data from January 1, 2019, to December 31, 2022, was conducted. 85.7% of distinct pregnancies received a CTNG screen. Of those tested, 68.6% underwent screening in the first trimester, and 8.3% of those screened in the first trimester were additionally screened in the third trimester following high-risk screening protocols. When adjusting for confounders, females testing positive at least once during their pregnancy were more likely to be screened according to first-trimester protocols if they were from income quintiles Q3 (p=0.047), Q4 (p=0.27), or Q5 (p=0.003) compared to individuals from Q1, the lowest income quintile. Individuals from southern Alberta health zones were less likely to be screened in the first trimester (p=0.026) compared to those from northern Alberta health zones.
  An “at delivery” CTNG screening program was established at the Royal Alexandra Hospital (RAH) in Edmonton, Alberta. Females delivering at the RAH were approached to participate in CTNG screening at delivery (17.7%), and 11.5% of females approached opted out of screening, with the majority citing the decision not to provide a sample as their primary reason for opting out (71.1%). In total, 15.7% of the target population provided a sample for testing, with 2.20% of results positive for a CT, NG, or CTNG infection. Results from this study were similar to proportions observed in the previous year from province-wide high-risk screening (14.2% screened following high-risk protocol and 2.40% positive).
  In conclusion, this thesis develops a complete antibiogram for provincial NG isolates, describes factors associated with the likelihood of being screened following first-trimester CTNG screening guidelines, and identifies barriers and perspectives on universally screening individuals at a later perinatal time point.

• Subjects / Keywords

  • Prenatal
  • Chlamydia trachomatis
  • Neisseria gonorrhoeae
  • Prenatal screening
  • diagnosis
  • STI
  • Chlamydia
  • Gonorrhea

• Graduation date

  Fall 2024

• Type of Item

  Thesis

• Degree

  Master of Science

• DOI

  https://doi.org/10.7939/r3-t3ey-wp35

• License

  This thesis is made available by the University of Alberta Library with permission of the copyright owner solely for non-commercial purposes. This thesis, or any portion thereof, may not otherwise be copied or reproduced without the written consent of the copyright owner, except to the extent permitted by Canadian copyright law.