Synopsis
Distinguish incidental diverticulosis, symptomatic diverticular disease and acute diverticulitis, identify complicated infection early, and choose conservative, antimicrobial, radiological or surgical care proportionately.
- Diverticulosis means the presence of diverticula, diverticular disease means attributable chronic symptoms, and diverticulitis is acute inflammation that may be uncomplicated or complicated.
- Typical acute diverticulitis produces constant left lower-quadrant pain and tenderness with fever or raised inflammatory markers, but right-sided disease and atypical presentations occur.
- Peritonitis, abscess, fistula, obstruction, perforation or sepsis defines complicated disease and changes the setting, imaging urgency and treatment.
Key red flags
Persistent fever, focal mass, sepsis, failure to improve or CT fluid collection and extraluminal gas suggests a complication requiring hospital antibiotics and radiological or surgical source-control planning.
Investigation priorities
Detect physiological deterioration, dehydration and organ dysfunction that determines admission and urgency.
Management branches
Focal symptoms suggest acute diverticulitis but the person is systemically well with no complication signal.
- Check observations, hydration, peritonism, oral intake, immune status and comorbidity, considering urinary, gynaecological and malignant alternatives.
- Offer simple analgesia, consider a no-antibiotic strategy and give practical oral fluid and short-term diet advice without imposing prolonged restriction.
Key medicines
ParacetamolUse the standard adult oral dose within the current BNF maximum, reduced when low body weight, liver disease or other risk makes that necessary.
Oral antibiotic for selected diverticulitisChoose the current NICE and local oral regimen only for systemic illness, immunosuppression or significant comorbidity, adjusting for allergy, renal function and interactions.