Acute diverticulitis

Antimicrobial prescribing: NHS Lothian
NHS Lothian
  • For patients with acute uncomplicated diverticulitis who are immunocompetent and systemically well: consider a NO antibiotic prescribing strategy
  • Features of complicated diverticulitis requiring IV antibiotics:
    • intra-abdominal abscess
    • bowel perforation and peritonitis
    • sepsis
    • fistula into the bladder or vagina
    • intestinal obstruction
  • Source control is a vital part of management for complicated diverticulitis

Recommended investigations

  • Blood cultures prior to starting antibiotics.
  • Intra-operative or percutaneous drainage samples (if applicable)

Antibiotic recommendation

Amoxicillin 1g every 8 hours IV

AND

Gentamicin (use NHS Lothian Calculator located AMT intranet page)

AND

Metronidazole 400mg every 8 hours orally (500mg every 8 hours IV if oral route unavailable)

Penicillin allergy or known MRSA carriage:

Vancomycin IV (use NHS Lothian Calculator located AMT intranet page) - target trough level 10-15mg/L

AND

Gentamicin (use NHS Lothian Calculator located AMT intranet page)

AND

Metronidazole 400mg every 8 hours orally (500mg every 8 hours IV if oral route unavailable)

IV to oral stepdown

  • Review IV antibiotics within 48 hours OR as soon as imaging results available
  • In the absence of complications, consider IV to oral switch

Preferred:

Co-trimoxazole 960mg every 12 hours orally

PLUS

Metronidazole 400mg every 8 hours orally

Alternative:

Co-amoxiclav 625mg every 8 hours orally (Suitable for those ≤ 65 years old with a low risk of C.diff infection. See Prevention, diagnosis and management of CDI.)

Recommended total duration

  • Uncomplicated: 5 days total (IV + PO)
  • Complicated infection with adequate source control (either surgery or radiological drainage); 5 days total (IV + PO) post source control

Longer courses may be required for complex patients and abscess not amenable to drainage. Please discuss with microbiology