What is the recommended antibacterial treatment for colitis?

Recommended Antibacterial Treatment for Colitis

For Clostridioides difficile colitis, oral vancomycin 125 mg four times daily for 10 days is recommended for severe cases, while metronidazole 500 mg three times daily for 10 days is recommended for non-severe cases. 1, 2, 3

Disease Severity Assessment

Disease severity should guide treatment choice:

• Non-severe C. difficile colitis: stool frequency < 4 times daily, no signs of severe colitis, WBC < 15 × 10^9/L 2
• Severe C. difficile colitis: fever, hemodynamic instability, signs of peritonitis or ileus, marked leukocytosis, elevated serum creatinine, elevated serum lactate, or pseudomembranous colitis on endoscopy 2

First-Line Treatment Recommendations

Non-Severe C. difficile Colitis

• Metronidazole 500 mg three times daily orally for 10 days 1, 2, 3
• In non-epidemic situations with clear antibiotic-induced CDI, consider stopping the inducing antibiotic and observing clinical response for 48 hours, but follow patients closely for deterioration 1, 2

Severe C. difficile Colitis

• Vancomycin 125 mg four times daily orally for 10 days 1, 2, 3, 4
• Consider increasing vancomycin dosage to 500 mg four times daily for 10 days in severe cases 1
• Fidaxomicin 200 mg twice daily for 10 days is an alternative option 1, 2
• Avoid metronidazole in severe or life-threatening disease 1

Treatment for Recurrent C. difficile Infection

• For first recurrence: Fidaxomicin 200 mg twice daily for 10 days 1, 2
• Alternative for first recurrence: Vancomycin 125 mg four times daily for 10 days followed by either pulse or taper strategy 1, 2
• For multiple recurrent CDI unresponsive to repeated antibiotic treatment, fecal microbiota transplantation (FMT) in combination with oral antibiotic treatment is strongly recommended 1, 2

Important Considerations

• Avoid antiperistaltic agents and opiates in C. difficile infection 2, 3
• Discontinue the inciting antibiotic if possible 2, 3
• Oral vancomycin is not systemically absorbed when administered orally, making it ideal for treating intestinal infections 4
• Monitor renal function in patients >65 years of age during and after treatment with vancomycin, as nephrotoxicity can occur 4
• Clinical response should be the primary measure of treatment success rather than repeat stool testing 2

Surgical Considerations

• Consider colectomy in situations such as:
  • Perforation of the colon
  • Systemic inflammation with deteriorating clinical condition not responding to antibiotics
  • Toxic megacolon
  • Severe ileus 1, 2, 3
• Surgery should preferably be performed before colitis becomes very severe (before serum lactate exceeds 5.0 mmol/L) 1, 2

Regional Variations in Practice

• While European and American guidelines now recommend fidaxomicin as first-line treatment with vancomycin as second choice, the Swiss Infectious Diseases Society still recommends metronidazole as first-line treatment for patients without risk factors and with low probability of relapse 5
• Cost considerations may influence treatment choice, as metronidazole is considerably more economical than vancomycin 6, 7

Treatment Efficacy

• Studies have shown equivalent efficacy and relapse rates between metronidazole and vancomycin for C. difficile-related diarrhea and colitis 6
• Fidaxomicin has been shown to be as effective as vancomycin with lower relapse rates 7