• Inflammation of the urethra
  • Common manifestation of sexually transmitted infection (STI)
  • Frequently associated with dysuria, pruritus, and/or urethral discharge; classified as gonococcal (caused by Neisseria gonorrhoeae) and nongonococcal (caused by other bacteria, or less common autoimmune disorders [Reiter syndrome], trauma, or chemical irritation)



  • In 2021, there were 1,644,416 reported cases of chlamydia, the most commonly reported bacterial STI, which is a 4.1% increase from 2020.
  • Young people aged 14 to 25 years comprise 2/3 of newly diagnosed chlamydial infections.
  • About 1 in 20 young women between 14 and 24 years of age have chlamydia.
  • In 2021, there were 710,151 reported cases of gonorrhea, the second most commonly reported bacterial STI; rates of gonorrhea have increased by 118% since 2009.
  • For both chlamydia and gonorrhea, rates have increased among men and women, among most age groups, as well as among most racial/ethnic groups.
  • In 2021, there were a total of 176,713 reported cases of syphilis.
  • The number of primary and secondary syphilis cases—the most infectious stages of syphilis—increased 28.6% to 53,767 cases from 2020 to 2021.

Etiology and Pathophysiology

  • Most common cause is infection via sexual transmission of N. gonorrhoeae, a gram-negative diplococcus.
  • N. gonorrhoeae is a gram-negative diplococcus that interacts with nonciliated epithelial cells → cellular invasion → inflammation, neutrophil production, and bacterial cell phagocytosis.
  • Sexually transmitted Chlamydia trachomatis infection is the most common cause of nongonococcal urethritis.
  • Other established pathogens:
    • Mycoplasma genitalium
    • Trichomonas vaginalis
    • Ureaplasma urealyticum
    • Herpes simplex virus (rare)
    • Adenovirus (rare)
  • Noninfectious causes (less common):
    • Chemical irritants (i.e., soaps, shampoos, douches, spermicides)
    • Foreign bodies
    • Urethral instrumentation

Risk Factors

  • Age 15 to 24 years
  • New sex partner
  • One or more sex partner(s)
  • History of coexisting STI
  • Sex partner with concurrent partner(s)
  • Inconsistent condom use outside a mutually monogamous relationship
  • Exchanging sex for money or drugs
  • Member of population with increased prevalence of infection, including incarcerated populations, military recruits, and economically disadvantaged populations

General Prevention

  • Use of male condoms, female condoms, or cervical diaphragms
  • Abstinence or reduction in the number of sex partners
  • Behavioral counseling

Commonly Associated Conditions

Annual chlamydia and gonorrhea screening is recommended for all sexually active women aged 24 years or younger as well as women aged 25 years and older with risk factors (B recommendation). There is insufficient evidence to recommend screening in men (1)[A].

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