aetiology

Last edited 09/2018

The majority of non gonococcal urethritis is a result of infection with

  • Chlamydia Trachomatis – more likely to be seen in younger patients
  • Mycoplasma genitalium – causes more symptoms (1)

Both organisms seldom coexist in the same individual. In around 30-80% of NGU patients neither C. trachomatis nor M. genitalium can be detected (1)

Other aetiological factors include:

  • Trichomonas vaginalis
    • more common in non-white ethnic groups
    • isolation is greater in men >30 years
  • bacterial infections, e.g. Ureaplasma urealyticum which may account for 5%–10% of cases of acute NGU
  • upper urinary tract infections – 6 % of cases
  • herpes simplex – less common 2-3%
  • Adenovirus – seen in 2-4% of symptomatic patients, conjunctivitis is often seen in these patients as well
  • rarely N. meningitidis, Haemophilus sp., Candida sp., urethral stricture and foreign bodies
  • condyloma accuminata
  • trauma - mechanical or chemical
  • cancer of the penis
  • primary syphilis
  • upper urinary tract abnormalities (1,2)

Reference:

  1. Horner P et al. 2015 UK National Guideline on the management of non-gonococcal urethritis. Int J STD AIDS. 2016;27(2):85-96.
  2. British Association for Sexual Health and HIV. 2007 UK National Guideline on the Management of Nongonococcal Urethritis