Bulletin Autumn‧Winter 1997

HlGHLIGHTS OF RGC-FUNDED PROJECTS Fig. 1 Peptic ulcer seen under endoscopy Fig. 2 Helicobacter pylori seen under an electronic microscope developed wh i ch merely suppress acid secretion w i t hou t changing the natural history o f the disease. Once medication is discontinued, ulcers invariably recur w i t h i n a f ew months. Helicobacter Pylori (HP) Closely Associated with the Disease I n 1983, researchers i n Australia discovered a bacterium residing i n the stomach of patients w i th chronic gastritis (inflammation of the stomach). Further studies s h owe d that this ba c t e r i um, subsequently called Helicobacter pylori (fig. 2 )， was f ound i n at least 90 per cent of patients suffering f r om peptic ulcers. The bacteria protect themselves f r om the high acidity i n the stomach by producing 'urease' in the gastric mucosa, wh i ch is an enzyme that metabolizes urea and n e u t r a l i z e s gastri c a c i d. T h ey also elaborate various toxic substances wh i c h i n d u c e i n f l amma t i on a nd caus e cell d ama g e i n t he s t oma ch a n d t he duodenum. HP Infection Treatment vs Acid Suppression Treatment I n view of these findings, Prof. Joseph Sung of the Department o f Medicine and Therapeutics, togethe r w i th Prof. Sydney Chung of the Department o f Surgery and Prof. Augustine Cheng of the Department of Microbiology, resolved to study the effects of treating HP infection o n the healing and recurrence o f peptic ulcers. T h e i r r e s ea r c h r e c e i v ed a g r ant of HK$386,000 f r om the Research Grant s Council in 1993. The researchers first studied a group of 153 patients w i t h duodenal ulcer, the mo r e c ommon type o f peptic ulcers. These patients w i t h HP infectio n and duodena l ulcers we r e r andom i z e d to receive either a one-week course of a three-drug regimen (bismuth , tetracycline and metronidazole) to treat HP infection, or four weeks of omeprazole (a potent acid suppression drug) in addition to the t h r ee - d r ug regimen. As a result, HP infection was cured in over 90 pe r cent of cases i n b o t h groups. There was, however, no significant difference in ulcer healing between th e t wo groups despite the fact that one group o f patients had not received an y medication for acid suppression. I n a second study, 50 patients w i t h gastric ulcer on a one-week course of the three-drug regime n was compared to 50 Chinese University Bulletin Autumn . Winter 1997 2 8