1. Division of Gastroenterology and Hepatology, University Medicine Cluster, National University Health System, Singapore
2. Yong Loo Lin School of Medicine, National University of Singapore, Singapore
3. Division of Rheumatology, University Medicine Cluster, National University Health System, Singapore
4. Department of Medicine, The University of Hong Kong, Hong Kong, China
5. Department of Dermatology, Division of Dermato-Allergy, University of Minnesota, Minneapolis, MN, USA