Efficacy and Safety of Nonantibiotic Outpatient Treatment in Mild Acute Diverticulitis (DINAMO-study): A Multicentre, Randomised, Open-label, Noninferiority Trial

Ann Surg. 2021 Nov 1;274(5):e435-e442. doi: 10.1097/SLA.0000000000005031.


Objective: Mild AD can be treated safely and effectively on an outpatient basis without antibiotics.

Summary of background data: In recent years, it has shown no benefit of antibiotics in the treatment of uncomplicated AD in hospitalized patients. Also, outpatient treatment of uncomplicated AD has been shown to be safe and effective.

Methods: A Prospective, multicentre, open-label, noninferiority, randomized controlled trial, in 15 hospitals of patients consulting the emergency department with symptoms compatible with AD.The Participants were patients with mild AD diagnosed by Computed Tomography meeting the inclusion criteria were randomly assigned to control arm (ATB-Group): classical treatment (875/125 mg/8 h amoxicillin/clavulanic acid apart from anti-inflammatory and symptomatic treatment) or experimental arm (Non-ATB-Group): experimental treatment (antiinflammatory and symptomatic treatment). Clinical controls were performed at 2, 7, 30, and 90 days.The primary endpoint was hospital admission. Secondary endpoints included number of emergency department revisits, pain control and emergency surgery in the different arms.

Results: Four hundred and eighty patients meeting the inclusion criteria were randomly assigned to Non-ATB-Group (n = 242) or ATB-Group (n = 238). Hospitalization rates were: ATB-Group 14/238 (5.8%) and Non-ATB-Group 8/242 (3.3%) [mean difference 2.58%, 95% confidence interval (CI) 6.32 to -1.17], confirming noninferiority margin. Revisits: ATB-Group 16/238 (6.7%) and Non-ATB-Group 17/242 (7%) (mean difference -0.3, 95% CI 4.22 to -4.83). Poor pain control at 2 days follow up: ATB-Group 13/230 (5.7%), Non-ATB-Group 5/221 (2.3%) (mean difference 3.39, 95% CI 6.96 to -0.18).

Conclusions: Nonantibiotic outpatient treatment of mild AD is safe and effective and is not inferior to current standard treatment.

Trial registration: ClinicalTrials.gov (NCT02785549); EU Clinical Trials Register (2016-001596-75).

Publication types

  • Equivalence Trial
  • Multicenter Study
  • Randomized Controlled Trial

MeSH terms

  • Acute Disease
  • Adolescent
  • Adult
  • Aged
  • Aged, 80 and over
  • Ambulatory Care / methods*
  • Anti-Bacterial Agents
  • Disease Management*
  • Diverticulitis, Colonic / diagnosis
  • Diverticulitis, Colonic / therapy*
  • Female
  • Follow-Up Studies
  • Humans
  • Male
  • Middle Aged
  • Outpatients*
  • Prospective Studies
  • Tomography, X-Ray Computed
  • Young Adult


  • Anti-Bacterial Agents

Associated data

  • ClinicalTrials.gov/NCT02785549