Predictors for Successful Treatment of Infected Necrotizing Pancreatitis with Antibiotics Alone: A Nationwide Prospective Cohort

Objective: To identify predictors for successful treatment of patients with infected necrotizing pancreatitis with antibiotics alone. Background: Infected necrotizing pancreatitis is associated with mortality ranging from 15-35%. Recent studies have shown that in some patients, treatment with antibiotics alone is successful, thus avoiding invasive procedures. Methods: We performed a post-hoc analysis of a prospective cohort of 305 patients with suspected or proven infected necrotizing pancreatitis from 22 Dutch hospitals. The primary outcome was successful treatment with antibiotics alone (i.e. survival without radiological, endoscopic or surgical intervention). All computed-tomography images were reviewed to classify the pattern of pancreatic necrosis. A prediction model using clinical and radiological predictors was created using multivariable logistic regression. A prognostic nomogram was developed based on the final predictors. Results: Overall, 86 out of 305 patients (28%) with infected necrotizing pancreatitis were successfully treated with antibiotics alone. Our final prediction model included presence of organ failure at the start of antibiotics (OR 0.46, 95%CI 0.22-0.99, P=0.046), presence of central necrosis (OR 0.11, 95%CI 0.05-0.23, P<0.001) and presence of subtotal necrosis (OR 0.12, 95%CI 0.03-0.36, P<0.001). The area under the curve was 0.74 (95%CI 0.70-0.75). The prognostic nomogram yielded a probability of successful antibiotic treatment of 5% when organ failure and central necrosis were present and 47% when all predictors were absent. Conclusion: In patients with infected necrotizing pancreatitis, predictors negatively impacting successful treatment with antibiotics are organ failure at the start of antibiotics, and the presence of central or subtotal necrosis on imaging.