Causes of UTI in Males
The primary causes of urinary tract infections (UTIs) in males include urinary tract obstruction, anatomical abnormalities, instrumentation, and sexually transmitted infections, with specific pathogens varying based on age and risk factors 1.
Common Causes of UTIs in Males
Anatomical and Functional Factors
- Urinary tract obstruction: Prostatic enlargement, urethral strictures, and calculi
- Anatomical abnormalities: Congenital malformations or acquired structural changes
- Instrumentation: Recent urinary catheterization or urologic procedures
- Incomplete bladder emptying: Neurogenic bladder or prostatic hyperplasia
Infectious Agents
Age <35 years: Primarily sexually transmitted pathogens
- Chlamydia trachomatis
- Neisseria gonorrhoeae
- Sexually transmitted E. coli (especially in men who have insertive anal intercourse) 2
Age >35 years: Primarily gram-negative enteric organisms
- Escherichia coli (most common)
- Klebsiella species
- Enterobacter species
- Proteus mirabilis and Proteus vulgaris 3
Risk Factors
- Recent urinary tract instrumentation or surgery
- Anatomical abnormalities of the urinary tract
- Prostatic disease: BPH, prostatitis
- Sexual activity: New sexual partners, unprotected intercourse
- Diabetes mellitus: Poor glycemic control increases UTI risk 1
- Advanced age: Associated with increased incidence of complicating factors
- Immunosuppression: HIV infection, transplant recipients
Clinical Presentations of UTIs in Males
Urethritis
- Urethral discharge
- Dysuria
- Urethral itching or burning
Cystitis
- Dysuria
- Frequency
- Urgency
- Suprapubic pain
Prostatitis
- Perineal, suprapubic, or low back pain
- Dysuria
- Fever (in acute bacterial prostatitis)
- Recurrent UTIs (in chronic bacterial prostatitis) 4
Epididymitis
- Unilateral testicular pain and tenderness
- Hydrocele
- Palpable swelling of the epididymis
- Often accompanied by urethritis (which may be asymptomatic) 2
Pyelonephritis
- Fever
- Flank pain
- Costovertebral angle tenderness
- Systemic symptoms (nausea, vomiting)
Diagnostic Approach
Essential Tests
- Urinalysis: Look for pyuria (increased polymorphonuclear leukocytes), bacteriuria, and nitrites 1
- Urine culture: Obtain before starting antibiotics to identify causative organism and susceptibility
- Significant bacteriuria defined as ≥50,000 CFUs/mL of a single uropathogen 1
- Urethral swab (in suspected STI cases): For Gram stain and culture or nucleic acid amplification testing 2
Additional Evaluation for Males with UTI
- Evaluation for anatomical abnormalities or obstruction may be warranted
- Prostate examination: To assess for prostatitis, especially in recurrent UTIs
- Imaging studies: Consider in recurrent or complicated UTIs
Treatment Approaches
Uncomplicated UTI
- First-line options:
- Trimethoprim-sulfamethoxazole: 160/800 mg (1 DS tablet) twice daily for 10-14 days 3
- Fluoroquinolones (e.g., ciprofloxacin, levofloxacin) when susceptibility is known
Epididymitis
For likely gonococcal or chlamydial infection (age <35 years):
- Ceftriaxone 250 mg IM single dose PLUS
- Doxycycline 100 mg orally twice daily for 10 days 2
For likely enteric organisms (age >35 years):
- Ofloxacin 300 mg orally twice daily for 10 days 2
Prostatitis
Acute bacterial prostatitis:
- Fluoroquinolones or trimethoprim-sulfamethoxazole for 4 weeks 4
Chronic bacterial prostatitis:
- Prolonged antibiotic therapy (6-12 weeks) with agents that penetrate prostatic tissue
- Trimethoprim-sulfamethoxazole or fluoroquinolones preferred 4
Prevention Strategies
- Adequate hydration: Increasing fluid intake reduces recurrent UTI risk 1
- Proper hygiene: Avoiding harsh cleansers that disrupt normal flora
- Voiding after sexual intercourse 1
- Treatment of underlying conditions: Managing diabetes, prostatic disease
- Consider non-antibiotic preventive measures for recurrent UTIs:
Special Considerations
- Asymptomatic bacteriuria should generally not be treated in most male populations 2, 1
- Drug interactions should be considered in elderly patients due to common polypharmacy 1
- Antimicrobial stewardship: Use narrow-spectrum antibiotics when possible to reduce resistance 6
- Follow-up: Persistent symptoms after 3 days require reevaluation of diagnosis and therapy 2
Pitfalls to Avoid
- Failure to obtain cultures before starting antibiotics
- Inadequate treatment duration, especially for prostatitis
- Not evaluating for underlying anatomical or functional abnormalities in males with UTI
- Treating asymptomatic bacteriuria unnecessarily
- Not considering sexually transmitted infections in younger males with urinary symptoms