[1] Greenslopes Hosp, Gallipoli Med Res Fdn, Brisbane, Qld, Australia
[2] Princess Alexandra Hosp, Dept Gastroenterol & Hepatol, Brisbane, Qld 4102, Australia
[3] Univ Calif Los Angeles, Med Ctr, Dept Internal Med, Los Angeles, CA 90024 USA
[4] Univ Queensland, Dept Med, Brisbane, Qld 4000, Australia