Infection (most common cause):

• Bacterial cystitis (e.g., E. coli, S. saprophyticus)
  • Rationale: Dysuria, frequency, urgency, suprapubic pain.
• Sexually transmitted infections (e.g., Chlamydia, Gonorrhea)
  • Rationale: Often accompanied by vaginal discharge or pelvic pain.
• Vaginitis (e.g., yeast, bacterial vaginosis)
  • Rationale: May cause external dysuria due to inflammation.

• Non-infectious causes:
  • Urethral stricture (post-inflammatory or traumatic)
    • Rationale: May present with weak stream, straining.
  • Interstitial cystitis/bladder pain syndrome (IC/BPS)
    • Rationale: Chronic pelvic pain, urinary urgency.
  • Chemical irritants (e.g., spermicides, soaps)
    • Rationale: External dysuria without systemic symptoms.

• Next steps:
  • Urinalysis (leukocytes, nitrites, RBCs) to assess for infection.
  • Culture if symptoms persist or recurrent.
  • Consider pelvic exam for STIs/vaginitis if indicated.