What is the recommended treatment for acute on chronic prostatitis with a urine culture showing greater than 100,000 Colony-Forming Units per milliliter (CFU/mL) of Group B Streptococcus?

Treatment for Acute on Chronic Prostatitis with Group B Streptococcus

For acute on chronic prostatitis with urine culture showing Group B Streptococcus (>100,000 CFU/mL), penicillin or another beta-lactam antibiotic should be the first-line treatment for at least 4 weeks. 1, 2

Antibiotic Selection

Group B Streptococcus (GBS) is a gram-positive organism that is predictably susceptible to penicillin and other beta-lactams as noted in your culture results. The treatment approach should be:

1. First-line options:

   • Penicillin G: Due to excellent activity against GBS
   • Amoxicillin: 500 mg three times daily
   • Amoxicillin-clavulanate: 875/125 mg twice daily

2. For penicillin-allergic patients:

   • Ceftriaxone: 1-2 g daily (if no anaphylactic reaction history)
   • Levofloxacin: 500 mg once daily 2
   • Trimethoprim-sulfamethoxazole: If susceptibility confirmed 3

Duration of Treatment

• Minimum treatment duration: 4 weeks 3, 4
• For acute on chronic prostatitis, longer courses (6-12 weeks) may be necessary to prevent relapse 3
• Clinical improvement should be evident within 2-4 weeks; if no improvement is seen, treatment should be reassessed 5

Monitoring and Follow-up

• Clinical reassessment after 2 weeks of treatment 1
• Repeat urine culture at the end of treatment to confirm eradication 1
• Consider PSA measurement 3 months after resolution if elevated during infection 1
• Use NIH-Chronic Prostatitis Symptom Index (NIH-CPSI) to quantify symptoms and monitor treatment response 1

Important Considerations

• Prostate penetration: Beta-lactams have variable penetration into prostatic tissue, but higher doses and longer duration can overcome this limitation for susceptible organisms like GBS
• Biofilm formation: Chronic prostatitis may involve bacterial biofilms that require extended therapy
• Supportive measures:
  • Adequate hydration
  • Pain management with NSAIDs if needed
  • Alpha-blockers (e.g., tamsulosin) may help with urinary symptoms 1, 2

Common Pitfalls to Avoid

1. Inadequate treatment duration: Treating for less than 4 weeks significantly increases relapse risk 3, 4
2. Inappropriate antibiotic selection: Using antibiotics with poor prostatic penetration
3. Failure to follow up: Not confirming microbiological cure with repeat cultures
4. Missing complications: Not evaluating for prostatic abscess in patients with persistent fever or symptoms despite appropriate antibiotics

If symptoms persist despite appropriate antibiotic therapy, further evaluation for anatomical abnormalities, prostatic calculi, or abscess formation should be considered.