Chlamydia trachomatis

Chlamydia trachomatis

General Information

Chlamydia is the most common bacterial cause of sexually transmitted infection (STI) in both males and females. While the majority of patients are asymptomatic, the most frequent manifestation of uncomplicated C. trachomatis is urethritis in males and cervicitis in females. Proctitis, lymphogranuloma venerum, prostatitis, PID and other complications can also occur.


On all genital STI samples, Island Health uses a molecular STI Pathogen Panel that tests for Chlamydia trachomatisNeisseria gonorrhoea and Trichomonas vaginalis. All requests for Chlamydia trachomatis and/or Neisseria gonorrhoea and/or Trichomonas vaginalis will result in testing for all three pathogens from any genital sample. The new combined assay is referred to as the STI Pathogen Panel and this is now the preferred order.

Preferred testing specimen varies by syndrome. Please ensure the correct STI swab is submitted to avoid rejection:

  • A vaginal swab (can be self collected) is preferred in women.
  • First catch urine can also be done in women but it is somewhat less sensitive than vaginal swab. Volume of urine for STI testing should be no more than 60 mL.
  • First catch urine is preferred in men; a urethral swab can also be collected. Volume of urine for STI testing should be no more than 60 mL.
  • A rectal swab should be collected if proctitis or LGV is suspected. All positive samples are referred to BCCDC for testing that distinguishes between regular and LGV strains of Chlamydia trachomatis.
  • Testing can also be performed on other swabs (e.g. conjunctival, throat).

Treatment for Uncomplicated Chlamydia

  • Patients with persistent symptoms are usually re-infected and should be retreated as primary treatment failure with adherence is rare
  • With adherence, cure is achieved in 95% of patients
  • Resistance to tetracyclines and macrolides is rare; both are first line
  • Choose azithromycin if patient is unlikely to comply to treatment
  • Treatment of infections outside the genitourinary tract warrant a referral to an appropriate specialty (e.g. Ophthalmology, Infectious Diseases)

Safe in pregnancy and breastfeeding


Do not use if pregnant or breastfeeding

Second Line Alternatives

Not a benefit; requires special authority

Not appropriate for pregnant women or children < 18 y/o

Ciprofloxacin or Moxifloxacin should not be substituted; Ofloxacin is not readily available

Alternative in Pregnancy

Perform test of cure

Extra-genital and Complicated Chlamydia


Chlamydia trachomatis