Chao-Feng Chang1, Tien-Yu Huang1, Te-Yu Lin2. 1. Division of Gastroenterology, Department of Internal Medicine, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan. 2. Division of Infectious Diseases and Tropical Medicine, Department of Internal Medicine, Tri-Service General Hospital, National Defense Medical Center, No. 325, Section 2, Cheng-Kung Road, Neihu District, Taipei, 11490, Taiwan. lin.deyu@msa.hinet.net.