Development and Diagnostic Accuracy of a Breath Test for Pancreatic Exocrine Insufficiency in Chronic Pancreatitis

Objective To develop a C-13-labeled substrate breath test by defining the optimal C-13-labeled substrate, substrate dose, test meal, and duration of the test and evaluating its accuracy for the diagnosis of pancreatic exocrine insufficiency (PEI) in chronic pancreatitis (CP). Methods Five consecutive prospective comparative studies in patients with known advanced CP and healthy controls were performed to develop the optimal breath test. Coefficient of fat absorption was used as the reference method. The diagnostic accuracy of the optimized breath test was prospectively further evaluated in patients with advanced CP using coefficient of fat absorption as the reference method. Results The optimal breath test protocol was that using 250 mg of C-13-mixed triglyceride as substrate together with a test meal containing 16 g of fat. Coefficient of fat absorption and breath test results correlated significantly (r = 0.736, P < 0.001). The test has sensitivity, specificity, and overall accuracy of 92.9%, 91.7%, and 92.3%, respectively, for the diagnosis of PEI. Conclusions The optimized C-13-mixed triglyceride breath test is an accurate and simple breath test for the diagnosis of PEI in patients with CP, easily applicable to the clinical routine.