1. Department of Gastroenterology and Hepatology, Guangzhou Digestive Disease Center, Guangzhou First People's Hospital, School of Medicine, South China University of Technology, Guangzhou, Guangdong 510180, P.R. China
2. Department of Internal Medicine, Guangzhou No. 8 People's Hospital, Guangzhou, Guangdong 510180, P.R. China
3. Department of Pediatrics, Guangzhou First People's Hospital, School of Medicine, South China University of Technology, Guangzhou, Guangdong 510180, P.R. China