What is the most common cause of dysuria (painful urination) in males?

Most Common Cause of Dysuria in Males

Urinary tract infection (UTI) is the most common cause of dysuria in males, with the specific etiology varying significantly by age: sexually transmitted organisms (particularly Chlamydia trachomatis) predominate in younger men under 35 years, while coliform bacteria (especially E. coli) are most common in older men, typically associated with prostatic hypertrophy and urinary stasis. 1, 2

Age-Stratified Etiologies

Younger Men (<35 years)

• Sexually transmitted infections are the primary cause of dysuria in this age group 1
• Chlamydia trachomatis accounts for 30-40% of nongonococcal urethritis cases and is the leading pathogen 3
• Chlamydial urethritis often presents with mild or absent symptoms, making it more prevalent than gonorrhea in asymptomatic cases 3
• Neisseria gonorrhoeae causes symptoms similar to chlamydia (urethral discharge, dysuria) but typically with more pronounced manifestations 3
• Epididymitis in sexually active men under 35 is most commonly caused by C. trachomatis or N. gonorrhoeae, usually accompanied by urethritis 3

Older Men (≥35 years)

• Coliform bacteria, particularly E. coli, are the predominant pathogens 1, 4
• Infection typically occurs secondary to urinary stasis from benign prostatic hyperplasia 1, 4
• Other gram-negative organisms (Proteus, Klebsiella, Pseudomonas, Serratia) and gram-positive organisms (Enterococcus) cause up to half of cases 5, 4
• Prostatitis should be considered and often cannot be excluded, requiring extended antibiotic courses 5

Diagnostic Approach

Essential Initial Evaluation

• Urinalysis (both dipstick and microscopic examination) is the cornerstone diagnostic test for most patients with dysuria 1, 2
• Urine culture with susceptibility testing should be obtained before initiating antimicrobial therapy, particularly in men where UTIs are classified as complicated 5
• The presence of pyuria, hematuria, or bacteriuria combined with clinical symptoms establishes a presumptive diagnosis 6
• A properly collected specimen yielding ≥10³ colony-forming units/mL of a single or predominant species confirms bacteriuria in men 3, 4

Age-Specific Testing Considerations

For men <35 years with dysuria:

• Obtain urethral swab or first-void urine for nucleic acid amplification testing for N. gonorrhoeae and C. trachomatis 3
• Gram stain of urethral exudate (>5 polymorphonuclear leukocytes per oil immersion field indicates urethritis) 3
• If persistent urethritis with negative initial testing, Mycoplasma genitalium testing is recommended 2

For men ≥35 years:

• Focus on identifying coliform bacteria and evaluating for underlying urological abnormalities (prostatic hypertrophy, urinary retention) 5, 1

Important Differential Diagnoses

Non-Infectious Causes to Consider

• Renal calculi can present with dysuria and should be considered when symptoms are atypical 1
• Genitourinary malignancy is more common in older men and may manifest as dysuria 1
• Bladder irritants (medications, chemical irritants) can cause dysuria without infection 2
• Spondyloarthropathy (Reiter's syndrome) presents with reactive arthritis, conjunctivitis, and urethritis, primarily in men with chlamydial infection 3

Common Diagnostic Pitfalls

• Vaginal discharge in female partners or other causes of urethritis may be misattributed to UTI 2
• Asymptomatic bacteriuria is common in elderly men (3.6-19% in community-dwelling men ≥70 years) but does not usually require treatment 3, 4
• Cloudy or malodorous urine alone should not be interpreted as symptomatic infection, especially in elderly or catheterized patients 3

Treatment Implications

Duration and Antibiotic Selection

• All UTIs in men are classified as complicated, requiring longer treatment courses than in women 5
• 14-day antibiotic course is recommended when prostatitis cannot be excluded 5
• Single-dose therapy is inadequate for men; recurrent infections require at least 6 weeks of treatment 4
• For younger men with STI-related dysuria, treatment must cover both C. trachomatis and N. gonorrhoeae 3

Empiric Therapy Options

• Amoxicillin plus aminoglycoside, second-generation cephalosporin plus aminoglycoside, or IV third-generation cephalosporin are recommended empiric options 5
• Ciprofloxacin may only be used when local resistance is <10%, entire treatment is oral, patient doesn't require hospitalization, and patient has β-lactam anaphylaxis 5
• Avoid fluoroquinolones if patient is from urology department or used fluoroquinolones in last 6 months 5

Follow-Up Requirements

• Monitor for symptom resolution and consider follow-up urine culture in complicated cases 5
• Evaluate for structural or functional urinary tract abnormalities that may contribute to infection, particularly in men with recurrent infections 5, 4
• Diagnostic evaluation is probably indicated only in young boys and men with recurrent or complicated infections 4