What are the diagnostic procedures and treatment options for prostatitis?

Prostatitis Diagnosis

The diagnosis of prostatitis depends on the clinical presentation: for acute bacterial prostatitis, obtain midstream urine culture and blood cultures without prostatic massage; for chronic bacterial prostatitis, perform the Meares-Stamey 4-glass test or 2-specimen variant to localize infection to the prostate. 1, 2

Acute Bacterial Prostatitis Diagnosis

Avoid prostatic massage or vigorous digital rectal examination in suspected acute bacterial prostatitis due to risk of bacteremia. 1, 2

Essential Diagnostic Steps

• Take a midstream urine dipstick to check for nitrite and leukocytes in patients with clinical suspicion 1
• Obtain midstream urine culture to identify causative organisms (typically gram-negative bacteria like E. coli, Klebsiella, or Pseudomonas in 80-97% of cases) and guide antibiotic selection 1, 2, 3
• Collect blood cultures in febrile patients to assess for bacteremia 1, 2
• Obtain complete blood count to evaluate for leukocytosis 1, 2
• Perform gentle digital rectal examination to assess for prostate tenderness (the prostate will be tender, boggy, and warm), but avoid vigorous massage 1, 2

Imaging When Indicated

• Perform transrectal ultrasound in selected cases to rule out prostatic abscess, particularly if patients fail to respond to initial antibiotic therapy or if abscess is clinically suspected 1, 2

Clinical Presentation to Recognize

Patients typically present with fever, chills, dysuria, urinary frequency, pelvic or perineal pain, and may have systemic symptoms including hypotension in severe cases 3, 4, 5

Chronic Bacterial Prostatitis Diagnosis

The Meares-Stamey 4-glass test is the gold standard for diagnosing chronic bacterial prostatitis, requiring a 10-fold higher bacterial count in expressed prostatic secretions compared to midstream urine. 1, 2, 6

The Meares-Stamey 4-Glass Test Protocol

• Collect first-void urine (VB1: initial 10 mL of voided urine) 6
• Collect midstream urine (VB2: midstream catch) 6
• Perform prostatic massage and collect expressed prostatic secretions (EPS) 6
• Collect post-massage urine (VB3: first 10 mL after massage) 6
• Perform aerobic culture and Gram stain on all specimens 6
• Positive diagnosis requires ≥10-fold higher bacterial count in EPS or VB3 compared to VB2 2, 6

Simplified 2-Specimen Variant

• Collect midstream urine and expressed prostatic secretions only for a less cumbersome alternative that maintains diagnostic accuracy 2, 6

Additional Diagnostic Evaluation

• Perform accurate microbiological evaluation for atypical pathogens such as Chlamydia trachomatis and Mycoplasma species in patients with chronic bacterial prostatitis 1
• Do not routinely perform microbiological analysis of ejaculate alone as it is insufficient for diagnosis 1

Common Pathogens

Up to 74% of chronic bacterial prostatitis cases are caused by gram-negative organisms, particularly E. coli, with other pathogens including Proteus mirabilis, Enterobacter species, and Serratia marcescens 2, 6

Clinical Presentation

Patients present with recurrent urinary tract infections from the same bacterial strain, pelvic pain, urinary symptoms (frequency, urgency, dysuria), and ejaculatory pain 3, 4, 5

Chronic Prostatitis/Chronic Pelvic Pain Syndrome (CP/CPPS)

CP/CPPS is a diagnosis of exclusion made when pelvic pain persists for at least 3 months with urinary symptoms, but without documented bacterial infection on urine cultures or localization studies. 2, 6, 3

Diagnostic Criteria

• Pelvic pain or discomfort for ≥3 months associated with urinary symptoms such as frequency, urgency, or dysuria 3
• Negative urine cultures and negative Meares-Stamey test (no bacterial localization to prostate) 2, 6
• Rule out other causes including urinary tract infection, prostate cancer, bladder cancer, urinary obstruction, urinary retention, and neurologic disease 6, 3

Essential Workup

• Complete medical history focusing on urinary symptoms, pelvic pain location and character, and ejaculatory pain 6
• Use validated symptom score questionnaires such as the NIH Chronic Prostatitis Symptom Index (NIH-CPSI, scale 0-43) to assess severity and quality of life impact 6, 3
• Digital rectal examination to estimate prostate volume and assess for tenderness 6
• Urinalysis to identify UTIs, proteinuria, hematuria, or glycosuria 6
• Postvoid residual measurement to exclude urinary retention 3
• Uroflowmetry to correlate symptoms with objective voiding dysfunction 6
• Bladder diary for ≥3 days in patients with storage symptoms or nocturia 6

Key Distinction

CP/CPPS is not caused by a culturable infectious agent and requires symptom-focused management rather than antimicrobials. 2, 6

Asymptomatic Inflammatory Prostatitis

This is an incidental finding during evaluation for infertility or prostate cancer, diagnosed by elevated white blood cells in prostatic secretions or semen without symptoms, and does not require treatment 4, 5, 7

Critical Diagnostic Pitfalls to Avoid

• Never perform prostatic massage in acute bacterial prostatitis as it can precipitate bacteremia and sepsis 1, 2
• Do not rely on ejaculate culture alone for chronic bacterial prostatitis diagnosis 1
• Do not diagnose CP/CPPS without excluding bacterial infection through proper localization cultures 2, 6
• Consider differential diagnoses including acute cystitis, benign prostatic hyperplasia, urinary tract stones, bladder cancer, prostatic abscess, and urethral stricture 4