A J Greenup1,2, D Wright3, D Koorey4. 1. General Medicine and Gastroenterology, Tamworth Base Hospital, Tamworth, New South Wales, Australia. astrid_jg@hotmail.com. 2. Academic Colorectal Unit, University of Sydney Medical School, Concord, New South Wales, Australia. astrid_jg@hotmail.com. 3. Academic Colorectal Unit, University of Sydney Medical School, Concord, New South Wales, Australia. 4. AW Morrow Gastroenterology and Liver Centre, Royal Prince Alfred Hospital, Camperdown, New South Wales, Australia.