Treatment of Bacterial Prostatitis
Acute Bacterial Prostatitis
For acute bacterial prostatitis, initiate empiric broad-spectrum antibiotics immediately targeting Enterobacterales (primarily E. coli), with fluoroquinolones as first-line oral therapy or intravenous beta-lactams for severe cases, continuing for 2-4 weeks total. 1, 2
Diagnostic Approach
- Obtain midstream urine culture before starting antibiotics to identify the causative organism and guide therapy 1, 2
- Collect blood cultures in febrile patients to assess for bacteremia 2
- Perform gentle digital rectal examination only—avoid vigorous prostatic massage or manipulation due to risk of inducing bacteremia 1, 2
- Consider transrectal ultrasound in selected cases to rule out prostatic abscess 2
Pathogen Profile
- Gram-negative bacteria cause 80-97% of acute bacterial prostatitis cases, predominantly E. coli, followed by Klebsiella pneumoniae and Pseudomonas aeruginosa 2, 3
- Gram-positive organisms including Staphylococcus aureus, Enterococcus species, and Group B streptococci account for the remainder 2
Treatment Selection
Outpatient Management (Mild-Moderate Cases):
- Ciprofloxacin 500-750 mg orally twice daily for 2-4 weeks if local fluoroquinolone resistance is <10% 2, 4, 3
- Levofloxacin 500-750 mg orally once daily for 2-4 weeks as an alternative 2, 5, 3
- Avoid amoxicillin or ampicillin empirically due to very high worldwide resistance rates 2
Inpatient Management (Severe Cases or Unable to Tolerate Oral Medications):
- Hospitalize patients with systemic illness, inability to void, intolerance of oral intake, or risk factors for antibiotic resistance 2, 6
- Initiate intravenous therapy with ceftriaxone, piperacillin-tazobactam, or ciprofloxacin 400 mg IV twice daily 2, 3, 6
- Switch to oral antibiotics once clinically improved (typically after 48-72 hours) and complete 2-4 weeks total therapy 2
Critical Considerations
- Local resistance patterns should guide antibiotic selection—fluoroquinolones should only be used empirically when resistance is <10% 2
- For healthcare-associated infections with suspected enterococci, use ampicillin, piperacillin-tazobactam, or vancomycin based on susceptibility 2
- Stopping antibiotics prematurely can lead to chronic bacterial prostatitis—ensure completion of the full 2-4 week course 2
- Approximately 10% of acute bacterial prostatitis cases progress to chronic bacterial prostatitis, and another 10% develop chronic pelvic pain syndrome 7
Chronic Bacterial Prostatitis
For chronic bacterial prostatitis, prescribe fluoroquinolones (levofloxacin 500 mg once daily or ciprofloxacin 500 mg twice daily) for a minimum of 4 weeks, as these agents achieve superior prostatic tissue penetration compared to other antibiotic classes. 1, 2, 3, 8
Diagnostic Approach
- Perform the Meares-Stamey 4-glass test (first-void urine, midstream urine, expressed prostatic secretions, and post-massage urine) as the gold standard for diagnosis 2
- A simplified 2-specimen variant (midstream urine and expressed prostatic secretions only) can be used in routine practice 2
- Diagnosis requires a 10-fold higher bacterial count in expressed prostatic secretions compared to midstream urine 2
Pathogen Profile
- Up to 74% of chronic bacterial prostatitis cases are caused by gram-negative organisms, particularly E. coli 2, 3
- Other pathogens include Proteus mirabilis, Enterobacter species, Serratia marcescens, and Enterococcus faecalis 2, 5
- Chronic bacterial prostatitis encompasses a broader spectrum of species than acute prostatitis, potentially including atypical organisms like Chlamydia trachomatis and Mycoplasma species 1, 2
Treatment Regimen
First-Line Therapy:
- Levofloxacin 500 mg orally once daily for minimum 4 weeks (28 days) 2, 5, 3, 8, 9
- Ciprofloxacin 500 mg orally twice daily for minimum 4 weeks (28 days) as equally effective alternative 2, 4, 3, 8
- Both regimens demonstrate 75-77% microbiologic eradication rates and similar clinical success rates 8
Evidence Supporting Fluoroquinolones:
- Levofloxacin and ciprofloxacin are equivalent in efficacy, with microbiologic eradication rates of 75% and 76.8% respectively, and clinical success rates of 75% and 72.8% 8
- Levofloxacin offers the advantage of once-daily dosing and superior prostatic tissue penetration compared to ciprofloxacin 9
- FDA-approved indication for levofloxacin includes chronic bacterial prostatitis due to E. coli, Enterococcus faecalis, or methicillin-susceptible Staphylococcus epidermidis 5
- FDA-approved indication for ciprofloxacin includes chronic bacterial prostatitis with 28-day treatment duration 4
Treatment Duration and Follow-up
- Minimum treatment duration is 4 weeks (28 days), though more prolonged therapy may be required for severe or complicated infections 1, 2, 4, 3
- Clinical long-term success rates at 24-45 days after completion of therapy range from 66.7-76.9% 5
- Six-month relapse rates are similar for both levofloxacin and ciprofloxacin regimens 8
Important Caveats
- Increasing fluoroquinolone resistance is a significant clinical problem—obtain susceptibility testing before initiating therapy when possible 7
- Test for atypical pathogens (Chlamydia trachomatis, Mycoplasma species) if standard therapy fails, as these require specific antimicrobial therapy 2
- Biofilm formation by bacterial isolates may facilitate development of chronic bacterial prostatitis and contribute to treatment failure 7
- Do not treat catheter-associated asymptomatic bacteriuria in general, except before traumatic urinary tract interventions 1
Key Distinction: Chronic Prostatitis/Chronic Pelvic Pain Syndrome (CP/CPPS)
- CP/CPPS is not caused by culturable bacterial infection and requires different management focused on symptom relief rather than antimicrobials 2
- Fewer than 10% of prostatitis cases are confirmed to have bacterial infection—the majority are CP/CPPS 1, 2
- First-line therapy for CP/CPPS with urinary symptoms is α-blockers (tamsulosin, alfuzosin), not antibiotics 3