Outpatient Management of Uncomplicated Diverticulitis: A Paradigm Shift in Colorectal Care

Abstract Over the past two decades, the management of acute uncomplicated diverticulitis (AUD) has undergone a substantial paradigm shift, moving from routine hospitalization and antibiotic therapy toward selective outpatient, non-antibiotic management. Historically, inpatient treatment with intravenous antibiotics and bowel rest was considered standard practice because of concerns regarding perforation and sepsis. However, advances in computed tomography (CT) have enabled accurate differentiation between uncomplicated and complicated disease, allowing safe identification of low-risk patients suitable for ambulatory care. The DIVER trial established that outpatient management is comparable to inpatient care in terms of safety and recurrence, while significantly reducing healthcare costs and minimizing disruption to patients' daily lives. Randomized controlled trials, including AVOD, DIABOLO, DINAMO, and STAND, have consistently demonstrated that routine antibiotic therapy does not reduce complications, recurrence, need for surgery, or mortality in immunocompetent patients with CT-confirmed AUD. These findings are further supported by multiple meta-analyses and long-term follow-up data confirming the safety of omitting antibiotics. Contemporary guidelines now endorse a risk-stratified approach centered on supportive care, including diet liberalization, acetaminophen-based analgesia, hydration, early mobilization, and structured follow-up. Biomarkers such as C-reactive protein may assist in identifying patients at higher risk of complications and guide antibiotic initiation when appropriate. Despite robust evidence, adoption of non-antibiotic outpatient strategies remains variable, particularly in North America, owing to physician and patient concerns as well as medicolegal considerations. Outpatient management of AUD exemplifies value-based, patient-centered care. Implementation frameworks, multidisciplinary collaboration, and structured follow-up pathways are essential to safely expand antibiotic stewardship and optimize resource utilization in modern diverticulitis care.