What is the treatment for campylobacter and E. coli (Escherichia coli) infections in stool?

Treatment for Campylobacter and E. coli Infections in Stool

Azithromycin should be considered the first-line antibiotic treatment for Campylobacter infections, while most E. coli diarrheal infections are self-limiting and typically do not require antibiotic therapy unless specific indications are present. 1, 2

Treatment Algorithm for Campylobacter Infections

First-line therapy:

• Azithromycin: 500 mg daily for 3 days or 1 g single dose 1
  • Superior efficacy against Campylobacter, especially in areas with fluoroquinolone resistance
  • Well-tolerated with minimal side effects (primarily dose-related GI complaints)
  • Effective when started early in the illness course (within 72 hours of symptom onset)

Alternative therapy (if azithromycin unavailable):

• Fluoroquinolones (e.g., ciprofloxacin 500 mg twice daily for 3 days) 3
  • Note: Increasing fluoroquinolone resistance in Campylobacter worldwide limits effectiveness 4, 5
  • Treatment failures requiring rescue therapy have been reported in approximately 5% of cases 1

Key considerations for Campylobacter treatment:

• Antibiotics reduce symptom duration by approximately 1 day 1
• Treatment is most effective when started early in illness course
• Consider treatment particularly for:
  • Severe or prolonged symptoms
  • Immunocompromised patients
  • Patients with dysentery (bloody diarrhea)
  • Fever greater than mild

Treatment Algorithm for E. coli Infections

Most E. coli diarrheal infections:

• Supportive care only - most infections are self-limiting within 3-7 days 2
  • Oral rehydration with properly formulated oral rehydration solution
  • Maintain appropriate nutrition and diet

Specific E. coli types requiring treatment:

1. Enterotoxigenic E. coli (ETEC):

   • Ciprofloxacin 500 mg twice daily for 3 days 2, 3
   • Alternative: Azithromycin 500 mg daily for 3 days in areas with high fluoroquinolone resistance

2. Enteroinvasive E. coli (EIEC):

   • Azithromycin 500 mg daily for 3 days 1, 2

3. Enteroaggregative E. coli (EAggEC) with persistent symptoms:

   • Consider antibiotic treatment based on susceptibility testing 2

Important caution:

• Avoid antibiotics for suspected STEC (Shiga toxin-producing E. coli) infections 1
  • Fluoroquinolones, β-lactams, TMP-SMX, and metronidazole may increase risk of hemolytic uremic syndrome
  • Macrolides should also be avoided for STEC that produce Shiga toxin 2

Supportive Care for Both Infections

• Fluid replacement: Oral rehydration solution preferred over "clear liquids" 2
• Diet: Continue normal feeding; avoid unnecessary food restrictions 2
• Antimotility agents:
  • Adults with mild, non-bloody diarrhea: Loperamide may be used (4 mg initially, then 2 mg after each loose stool, maximum 16 mg/day) 2
  • Avoid antimotility agents in:
    • Children under 18 years
    • Patients with bloody diarrhea
    • Patients with fever
    • Suspected inflammatory diarrhea

Special Considerations

• Immunocompromised patients: Lower threshold for antibiotic treatment 1
• Severe illness: Consider hospitalization for IV fluids and electrolyte management 2
• Antibiotic resistance: Consider local resistance patterns when selecting therapy 1, 5
  • Fluoroquinolone resistance >85% in Southeast and South Asia
  • Emerging azithromycin resistance, though still limited

Common Pitfalls to Avoid

• Treating all E. coli infections with antibiotics, which may increase resistance and prolong bacterial shedding 1, 2
• Using antimotility agents in patients with bloody diarrhea or fever 2
• Failing to consider STEC in patients with bloody diarrhea (antibiotics may worsen outcomes) 1
• Delaying treatment of Campylobacter beyond 72 hours of symptom onset, which reduces effectiveness 1
• Using inappropriate oral rehydration fluids that may worsen osmotic diarrhea 2