What is the recommended approach for diagnosing and treating a male patient with a suspected urinary tract infection (UTI) during a physical exam?

Physical Examination and Diagnostic Approach for UTI in Adult Males

All UTIs in males are classified as complicated infections requiring urine culture before treatment, digital rectal examination to assess the prostate, and a minimum 14-day antibiotic course because acute bacterial prostatitis cannot be reliably excluded at initial presentation. 1

Essential Physical Examination Components

Abdominal and Suprapubic Assessment

• Palpate the suprapubic area to detect bladder distention, which indicates urinary retention and potential obstruction requiring urgent intervention 2, 1
• Assess for suprapubic tenderness suggesting cystitis or bladder inflammation 3

External Genitalia Examination

• Inspect the penis and urethral meatus for discharge, erythema, or lesions that would indicate urethritis rather than UTI 2, 3
• Examine the scrotum for swelling, erythema, or tenderness suggesting epididymitis 2
• In epididymitis, look for unilateral testicular pain and tenderness with palpable swelling of the epididymis and possible hydrocele 2

Digital Rectal Examination (Mandatory)

• Perform DRE gently to assess prostate size, consistency, symmetry, and tenderness 2, 1
• A tender, boggy, warm prostate indicates acute bacterial prostatitis, which requires immediate recognition because vigorous massage risks bacteremia 1, 4
• An enlarged, firm, symmetrical prostate suggests benign prostatic hyperplasia with secondary infection 1
• Assess anal sphincter tone as part of neurologic evaluation 2, 4

Neurologic Assessment

• Evaluate motor and sensory function in the perineum and lower extremities to identify neurogenic bladder as a predisposing factor 2
• Check for lower extremity edema suggesting fluid overload contributing to nocturia 3

Critical Diagnostic Testing (Mandatory Before Treatment)

Urinalysis with Microscopy

• Dipstick testing for pyuria, bacteriuria, hematuria, nitrites, and proteinuria is essential in all cases 2, 1, 3
• If dipstick is abnormal, perform microscopic examination and culture 2, 3
• Pyuria (≥5 WBCs per high-power field) supports infection but is not specific 1

Urine Culture with Susceptibility Testing

• Urine culture is mandatory in ALL male patients before initiating antibiotics because males have broader microbial spectrum and higher resistance rates than females 1, 3, 5
• Collect midstream clean-catch specimen yielding ≥10³ colony-forming units/mL for diagnosis 6
• E. coli remains most common, but other gram-negative and gram-positive organisms cause up to 50% of cases in males 6, 5

Post-Void Residual Measurement

• Measure post-void residual by transabdominal ultrasound to assess for urinary retention and obstruction 2, 1
• Repeat measurement if initially elevated due to marked intra-individual variability 2

Age-Based Differential Diagnosis Framework

Males <35 Years Old

• Sexually transmitted urethritis (Chlamydia trachomatis, Neisseria gonorrhoeae) is the primary consideration 2, 3
• Perform Gram stain of urethral exudate or intraurethral swab looking for >5 polymorphonuclear leukocytes per oil immersion field 2
• Obtain nucleic acid amplification test for N. gonorrhoeae and C. trachomatis on intraurethral swab or first-void urine 2
• Consider epididymitis if unilateral testicular pain and swelling present 2

Males >35 Years Old

• Enteric gram-negative organisms (E. coli, Proteus, Enterobacter) causing UTI secondary to prostatic hypertrophy or obstruction are most likely 2, 6
• Acute bacterial prostatitis must be excluded through careful DRE and symptom assessment for fever, chills, perineal pain, and obstructive voiding 1
• Assess for history of urinary instrumentation, catheterization, or anatomical abnormalities 2, 6

Additional Testing When Indicated

Frequency-Volume Chart (Voiding Diary)

• Record time and volume of each void for 3 consecutive days when nocturia or frequency is prominent 2, 3, 4
• Identifies nocturnal polyuria versus reduced bladder capacity 2, 3

Symptom Quantification

• Use International Prostate Symptom Score (I-PSS) with bother score to quantify lower urinary tract symptoms and guide treatment decisions 2, 3
• A 6-point change in NIH-CPSI is clinically meaningful for chronic prostatitis 4

Serum PSA (Selective)

• Discuss risks and benefits before testing, including false-positives, biopsy complications, and false-negative biopsies 2
• Only perform if life expectancy >10 years and prostate cancer diagnosis would change management 2
• PSA can predict prostate volume for treatment planning 2, 3

Immediate Urologic Referral Criteria (Before Treatment Initiation)

Refer immediately to urology if any of the following are present: 2, 3

• DRE findings suspicious for prostate cancer 2
• Gross or persistent microscopic hematuria 2
• Abnormal PSA requiring further evaluation 2
• Recurrent UTIs (≥2 episodes) 2
• Severe obstruction (Qmax <10 mL/second) 3
• Neurological disease affecting bladder function 3
• History of urolithiasis or upper tract involvement 2
• Recent onset nocturnal enuresis 2
• Renal insufficiency 2

Critical Pitfalls to Avoid

• Never treat empirically without urine culture in males due to higher resistance rates and broader pathogen spectrum 1, 5
• Never perform vigorous prostatic massage if acute prostatitis is suspected due to bacteremia risk 4
• Do not use single-dose or 3-day therapy in males—minimum 7-14 days required because prostatitis cannot be excluded 1, 6, 5
• Do not miss testicular torsion in younger males—if sudden severe pain with negative infection workup, obtain emergency surgical consultation 2
• Avoid fluoroquinolones as first-line agents unless treating complicated infection or pyelonephritis; reserve for more invasive infections 5

Empiric Treatment Pending Culture Results

For Suspected Uncomplicated UTI (Rare in Males)

• Trimethoprim-sulfamethoxazole 160/800 mg twice daily for 7-14 days is first-line if local resistance <20% 7, 5
• Nitrofurantoin 100 mg twice daily for 7 days is alternative first-line 5

For Suspected Prostatitis or Complicated UTI

• Fluoroquinolones (levofloxacin 500 mg daily or ofloxacin 300 mg twice daily) for 14 days minimum due to prostatic penetration 2, 5
• Adjust based on culture and susceptibility results 1, 5

For Suspected STI-Related Epididymitis (<35 years)

• Ceftriaxone 250 mg IM single dose PLUS doxycycline 100 mg orally twice daily for 10 days 2

For Enteric Organism Epididymitis (>35 years)

• Ofloxacin 300 mg orally twice daily for 10 days OR levofloxacin 500 mg daily for 10 days 2