Aetiology and assessment of urethritis

Urethritis is characterised by urethral irritation, dysuria or discharge. The most common bacterial causes of urethritis are Chlamydia trachomatis, Neisseria gonorrhoeae and Mycoplasma genitaliumOng, 2023. Other pathogens include adenoviruses, herpes simplex virus (HSV) and occasionally, Trichomonas vaginalis. In 50% or more of cases, no pathogen is identifiedOng, 2023.

Collect a first-pass1 urine sample for nucleic acid amplification testing (NAAT) (eg polymerase chain reaction [PCR]) for C. trachomatis and N. gonorrhoeae. Restrict testing for M. genitalium to patients with persistent urethritis despite empirical therapy, because treatment may be expensive and has uncertain efficacy. Other Mycoplasma and Ureaplasma species are often co-reported with M. genitalium NAAT results but do not require treatment for patients with urethritis2.

Distinguishing between gonococcal and nongonococcal urethritis is important to guide treatment. Gonococcal urethritis typically presents with a purulent discharge within a few days of acquisition, and is more common inOng, 2023:

  • gay, bisexual and other men who have sex with men, and transgender women
  • people who have recently had sex with a new partner in a country with a high prevalence of gonorrhoea (eg developing countries)
  • remote Aboriginal and Torres Strait Islander populations.

Health outcomes are significantly impacted by geographical, historical, socioeconomic, spiritual, emotional and cultural determinants. In Aboriginal and Torres Strait Islander peoples, the incidence of infection and increased risk of poor health outcomes can be linked to complex socioeconomic factors, including poverty, reduced access to health services, incarceration, discrimination and intergenerational trauma. A shared strengths–based approach to healthcare that recognises each patient's unique cultural determinants and circumstances is essential.

If urethral discharge is present, collect a swab for Gram stain, culture, and susceptibility testing of N. gonorrhoeae, because antimicrobial resistance is increasing and NAAT does not detect antimicrobial resistance. Urgent microscopy of a stained urethral smear can distinguish gonococcal from nongonococcal urethritis.

Note: Collect a urethral swab for Gram stain, culture, and susceptibility testing if gonorrhoea is suspected.

Gonococcal and chlamydial urethritis are commonly associated with extragenital (anorectal, pharyngeal) infection, especially in gay, bisexual and other men who have sex with men, and transgender women. Test these sites and treat accordingly.

For general principles of sexually transmissible infection (STI) management, including investigations and counselling, and considerations for children in whom an STI is identified, see Principles of STI management.

1 A first-pass urine specimen is the first part of the urine stream, and can be collected at any time of the day; see the diagnosis section of the relevant condition in the Australian STI Management Guidelines for Use in Primary Care for more information.Return
2 M. hominis, U. urealyticum and U. parvum are part of the normal genital flora. Treatment is not required if these organisms are identified from a urethral swab.Return