PANCREAS: Edited by Timothy B. GardnerBreath testing for the diagnosis of pancreatic diseaseDominguez-Muñoz, J. EnriqueAuthor Information Department of Gastroenterology and Hepatology, University Hospital of Santiago de Compostela, Santiago de Compostela, Spain Correspondence to J. Enrique Dominguez-Muñoz, MD, PhD, Professor of Medicine, Head of the Department of Gastroenterology and Hepatology, University Hospital of Santiago de Compostela, C/Choupana, s/n, 15706 Santiago de Compostela, Spain. Tel: +34 981 951 364; fax: +34 981 955 100; e-mail: Juan.Enrique.Dominguez.Munoz@sergas.es Current Opinion in Gastroenterology: September 2020 - Volume 36 - Issue 5 - p 421-427 doi: 10.1097/MOG.0000000000000664 Buy Metrics Abstract Purpose of review Pancreatic function tests are mainly used for the diagnosis of exocrine pancreatic insufficiency (EPI) in patients with pancreatic diseases or after pancreatic or gastric surgery. Breath tests evaluate not just pancreatic secretion but the digestion capacity of the pancreas. These tests are good candidates for the diagnosis of EPI as they are noninvasive, accurate and easy to apply to clinical practice. Recent findings The 13C-labelled mixed triglyceride (MTG) breath test has been optimized and validated against adequate reference methods for the diagnosis of EPI in patients with chronic pancreatitis and for the evaluation of the efficacy of pancreatic enzyme replacement therapy (PERT). In addition, reported 13C-MTG breath test results in patients with other pancreatic diseases and after pancreatic and gastric surgery support the accuracy and clinical applicability of this test. The evidence of pancreatic function breath tests with other 13C-labelled substrates is limited. Summary Increasing evidence supports the accuracy and clinical usefulness of the 13C-MTG breath test for the diagnosis of EPI and the evaluation of the efficacy of PERT in different clinical conditions. Commercial availability of this test is required for a wide clinical use. The use of optimized and validated breath test protocols is mandatory. Copyright © 2020 Wolters Kluwer Health, Inc. All rights reserved.