Background: Among the previous described noninvasive markers for screening of exocrine pancreatic insufficiency, fecal elastase-1 test has been reported to be the most satisfactory exocrine pancreatic function test. Recently, indirect tests such as breath tests have developed in which stable isotopes (13C) are incorporated into test meals. The aim of this study was to evaluate the diagnostic efficacy of 13C-labeled mixed triglyceride breath test as an exocrine pancreatic test for patients undergoing pancreatic resection.
Methods: The 13C-labeled mixed triglyceride breath test and fecal elastase-1 test were performed in 7 healthy subjects, 10 patients with chronic pancreatitis and 95 patients undergoing pancreatic surgery. The 95 pancreatic resections consisted of 42 pylorus-preserving pancreatoduodenectomies (PPPD), 9 pancreatic head resections with segmental duodenectomy, 14 local resections of head of the pancreas combined with longitudinal pancreaticojejunostomy for chronic pancreatitis (Frey procedure), 8 necrosectomies for necrotizing acute pancreatitis, 6 segmental resections of the pancreas (SR), 13 distal pancreatectomies (DP) and 3 total pancreatectomies (TP). All patients undergoing surgery were examined when about one year had passed since operation. After a 12-hour fast, 200 mg of 13C-labeled mixed triglyceride was orally administered with a test meal, and breath samples were taken before and at 1-hour intervals for 7-hour. Thereafter, the increase in 13C/12C isotopic ratio in breath was analyzed by mass spectrometry. The concentration of fecal elastase-1 was determined using an enzyme-linked immunosorbent assay (Schebo-Tech, Wettenberg, Germany).
Results: The 13CO2 cumulative recovery at 7-hour was found to be significantly correlated with the concentration of fecal elastase-1 (n = 112, R2 = 0.14, P < 0.0001). Not only the 13CO2 cumulative recoveries at 7-hour, but also fecal elastase-1 concentrations of patients undergoing PPPD, patients undergoing Frey procedure and patients undergoing TP were significantly lower than those of healthy volunteers (P < 0.05). On the fourth day after withdrawal of oral pancreatic enzyme supplement, 20/25 (80 %) patients with low 13CO2 cumulative recoveries (less than 5 %) showed symptoms of exocrine pancreatic insufficiency such as excessive volumes of stool or loose stool.
Conclusions: These results suggested that 13C-labeled mixed triglyceride breath test was an useful test for evaluating exocrine pancreatic function in patients undergoing pancreatic resection.