Management of acute diverticulitis in Stage 0-IIb: indications and risk factors for failure of conservative treatment in a series of 187 patients.

Left-sided acute diverticulitis in WSES Stage 0-IIb preferentially undergoes conservative management. However, there is limited understanding of the risk factors for failure of this approach. The aim of this study was to investigate the factors associated with the decision to perform conservative treatment as well as the predictors of its failure. We included patients with a diagnosis of WSES diverticulitis CT-driven classification Stage 0-IIb treated in the Emergency Surgery Unit of the Agostino Gemelli University Hospital Foundation between 2014 and 2020. The endpoints were the comparison between the characteristics and clinical outcomes of acute diverticulitis patients undergoing conservative versus operative treatment. We also identified predictors of conservative treatment failure. A set of multivariable backward logistic analyses were conducted for this purpose. The study included 187 patients. The choice for operative versus conservative treatment was associated with clinical presentation, older age, higher WSES grade, and previous conservative treatment. There were 21% who failed conservative treatment. Of those, major morbidity and mortality rates were 17.9% and 7.1%, respectively. A previously failed conservative treatment as well as a greater WSES grade and a lower hemoglobin value were significantly associated with failure of conservative treatment. WSES classification and hemoglobin value at admission were the best predictors of failure of conservative treatment. Patients failing conservative treatment had non-negligible morbidity and mortality. These results promote the consideration of a combined approach including baseline patients' characteristics, radiologic features, and laboratory biomarkers to predict conservative treatment failure and therefore optimize treatment of acute diverticulitis.