Urethritis

Definition | Aetiology | Pathophysiology | Risk Factors | Signs and Symptoms | Investigations | Management

Definition

Urethritis is inflammation of the urethra, commonly caused by sexually transmitted infections (STIs) or non-infectious irritants. It is classified into:

  • Gonococcal Urethritis (GU): caused by Neisseria gonorrhoeae.
  • Non-Gonococcal Urethritis (NGU): commonly caused by Chlamydia trachomatis, Mycoplasma genitalium, or other organisms.

Aetiology

Infectious Causes:

  • Sexually Transmitted Infections (STIs):
    • Neisseria gonorrhoeae (gonorrhoea).
    • Chlamydia trachomatis (most common cause of NGU).
    • Mycoplasma genitalium (resistant to standard treatment).
    • Trichomonas vaginalis (less common in the UK).
    • Ureaplasma urealyticum (associated with persistent urethritis).
  • Viral Infections: Herpes simplex virus (HSV), Adenovirus.

Non-Infectious Causes:

  • Mechanical trauma (e.g., catheterisation, vigorous sexual activity).
  • Chemical irritation (e.g., soaps, spermicides, antiseptics).
  • Reiter’s syndrome (reactive arthritis following infection).

Pathophysiology

  • Pathogens adhere to and invade the urethral epithelium, triggering inflammation.
  • Increased neutrophil activity leads to urethral discharge.
  • Persistent infection may cause complications like epididymitis, prostatitis, or urethral stricture.

Risk Factors

  • Unprotected sexual intercourse.
  • Multiple sexual partners.
  • History of STIs.
  • Recent use of irritants (e.g., spermicides, soaps).
  • Urinary catheterisation.
  • Engaging in anal sex (increases exposure to certain bacteria).

Signs and Symptoms

Common Symptoms:

  • Dysuria: burning sensation during urination.
  • Urethral discharge:
    • Gonococcal: thick, purulent yellow-green discharge.
    • Non Gonococcal: clear or mucoid discharge.
  • Urethral discomfort or itching.

Associated Symptoms:

  • Reactive arthritis: conjunctivitis, urethritis, arthritis (Reiter's syndrome).
  • Systemic symptoms: fever, lymphadenopathy (if severe or disseminated infection).

Investigations

  • First-void urine sample: nucleic acid amplification test (NAAT) for Chlamydia trachomatis and Neisseria gonorrhoeae.
  • Urethral swab: used if discharge is present (microscopy and culture for gonorrhoea).
  • Gram stain: gram negative diplococci suggest gonorrhoea.
  • Blood tests: HIV and syphilis screening (STI risk assessment).

Management

1. Empirical Antibiotic Treatment (Before Test Results):

  • Gonococcal Urethritis:
    • Ceftriaxone 1g IM (single dose) + Azithromycin 1g PO (single dose).
    • Alternative: Cefixime 400mg PO + Azithromycin 1g PO.
  • Non-Gonococcal Urethritis (NGU):
    • Doxycycline 100mg PO BD for 7 days OR Azithromycin 1g PO single dose.
    • Persistent/recurrent NGU: consider Mycoplasma genitalium, treat with Moxifloxacin 400mg OD for 10 days.

2. Partner Notification and STI Screening:

  • Sexual partners within the last 60 days should be tested and treated.
  • Advise abstinence from sexual activity until treatment is complete.

3. Symptomatic Relief:

  • Increase fluid intake to flush the urinary tract.
  • Paracetamol or ibuprofen for pain relief.
  • Avoid chemical irritants (soaps, spermicides).

4. Follow-Up:

  • Test of cure for gonorrhoea at 2 weeks post-treatment.
  • Persistent symptoms: repeat testing for alternative causes.
RenalmypanotesUrethritis