This prospective randomized study investigated the possibility that duodenal ulcer relapse associated with Helicobacter Pylori infection is mediated by oxygen-derived free radicals. To this end, the radical scavengers allopurinol (50 mg 4 times daily) and dimethyl sulphoxide (DMSO, 500 mg 4 times daily) were administered orally. One hundred and forty-six consecutive patients with previous symptomatic endoscopy proven duodenal ulceration, which had been shown endoscopically to have healed in the presence of gastric mucosal infection with Helicobacter Pylori, were randomized to receive for the period of one year either placebo, or cimetidine 400 mg at bedtime, or allopurinol, or DMSO. In one hundred and twenty-six patients evaluable for efficacy, the cumulative relapse at one year was: placebo 47%, cimetidine 24%, allopurinol 6% and DMSO 6%. Cimetidine was significantly effective in preventing the relapse (p < 0.01), however allopurinol and DMSO were superior to cimetidine in this respect (p < 0.05). In the patients who relapsed, ulcer recurrence tended to occur early in those on placebo and cimetidine and to be evenly distributed over the year in those on free radical scavenging therapy. In all groups, ulcer recurrence throughout the maintenance year was more frequently symptomatic than silent. The incidence of infection with Helicobacter Pylori was not influenced by any of the regimens employed and the bacterium was detected with every relapse noted in this study and during the follow-up endoscopy which was carried out at 6 months and at 12 months during the maintenance year. The results suggest that oxygen-derived free radicals are involved in the relapse of duodenal ulceration in patients infected with Helicobacter Pylori.
This review describes some of the mechanisms which are thought to be important in the causation of pain in chronic pancreatitis. Both medical and surgical techniques for treating this pain are described.
Refractory peptic ulceration refers to ulcers which are slow to heal despite active treatment for at least three months. Oxygen-derived free radicals are cytotoxic and promote tissue injury. Twelve consecutive patients with refractory peptic ulceration (eight with duodenal ulcers and four with solitary pre-pyloric gastric ulcers) were treated using the radical scavengers allopurinol or dimethyl sulphoxide. This treatment was well tolerated by all patients and produced no adverse effects. Endoscopic examination four weeks later demonstrated complete healing (an intact gastric or duodenal mucosa without any breaches) in all patients. The results suggest that oxygen-derived free radicals perpetuate the process of peptic ulceration and exert an adverse effect on healing. Scavengers of these radicals stimulate the healing of refractory gastric and duodenal ulceration.