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Resistant Duodenal Ulcer: When, Why and What to Do?

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Resistant Duodenal Ulcer: When, Why and What to Do? Postgraduate Medical Journal (1988) 64, 369-372 Postgrad Med J: first published as 10.1136/pgmj.64.751.369 on 1 May 1988. Downloaded from Difficult Decisions Resistant duodenal ulcer: when, why and what to do? R.P. Walt' and T.K. Daneshmend2 'Department of Medicine, Queen Elizabeth Hospital, Birmingham BJ5 2TH and 2Department of Therapeutics, Queen's Medical Centre, Nottingham NG7 2UH, UK. Introduction Duodenal ulceration is a chronic disease the causes Many people include ulcer relapse as evidence of of which remain unknown. Current medical treatment failure or resistance. Unfortunately treatment interrupts the natural history and relapse of duodenal ulcer is even less well accelerates ulcer healing. It does not cure ulcers. All understood and available data do not allow us to duodenal ulcers are generally considered together distinguish between expected and unexpected even though pathophysiological mechanisms differ relapse.6 A recent study has shown that asympto- from patient to patient. It should not be surprising matic relapse and subsequent healing are common that some duodenal ulcer patients respond relatively during maintenance and that most maintenance poorly. However, duodenal ulcers which do not trials have probably underestimated true ulcer heal in the 'usual' time have traditionally been recurrence by nearly half.7 There is also an unsub- labelled as difficult, refractory, intractable, stantiated belief that most ulcers which recur within copyright. stubborn, recalcitrant, persistent, or resistant. There a few days of stopping treatment had never really is no agreement on the definition of resistance and healed and were missed by endoscopists. For these such patients may merely represent one extreme of reasons we will not consider failure of long-term the 'normal' ulcer population. For the purposes of treatment any further. this article, our definition of resistant duodenal It is evident that the frequency of resistant ulcer is: The failure of a duodenal ulcer to heal duodenal ulcers changes with alternative definitions. after two months of full-dose treatment with an Ours is arbitrary and should be reconsidered as H2-receptor antagonist. newer drugs become available. It could be argued http://pmj.bmj.com/ that no ulcer should be labelled as resistant until it has failed to heal during treatment with the most Frequency of resistant ulceration potent gastric anti-secretory compounds such as the proton pump inhibitor omeprazole. Cimetidine given for 495 episodes of duodenal ulceration resulted in 83% and 93% healing after two and three months, respectively.' Thus 17% or 7% of duodenal ulcers could be regarded as What makes some duodenal ulcers resistant? on September 29, 2021 by guest. Protected refractory depending on your 'pet' definition. In other studies with H2 antagonists, 95% of duodenal In many studies lower healing rates for duodenal two of ulcer are found in those patients who are males, are ulcers were healed by months2 and review old, smoke, have large ulcers, consume analgesics, many healing trials suggests that an overall figure have low fasting serum gastrin, have high maximal for non-healed duodenal ulcers may be somewhat acid output in response to pentagastrin, and have higher at lO%,3'4 though in individual studies the nocturnal hypersecretion of gastric acid.8-"5 Of figure may be as low as 3%.5 As a consequence of these various factors, smoking is thought to be the relative rarity of resistant duodenal ulcer, few most important in delaying ulcer healing and studies have improved our understanding or have predicting relapse while the other factors are much compared the available treatment options. less consistent predictors. Indeed, in one study' 6 there were no clinical features that could distinguish Correspondence: R.P. Walt, M.D., M.R.C.P. between patients with responsive or refractory Received: 16 November 1987 ulcer. In another investigation' comparing 66 t The Fellowship of Postgraduate Medicine, 1988 Postgrad Med J: first published as 10.1136/pgmj.64.751.369 on 1 May 1988. Downloaded from 370 R.P. WALT AND T.K. DANESHMEND refractory with 105 responsive ulcer patients, there in acceleration of ulcer healing. Present thera- was no difference in sex ratio, smoking habits, ulcer peutic options include (a) continuing the same number, or basal and maximum secretion of acid H2 antagonist for longer, perhaps at a higher dose, and pepsin. However, refractory patients in this (b) changing to another H2 antagonist, (c) adding particular group were more likely to be younger, another agent, (d) changing to another conven- have a large ulcer, a family history of peptic ulcer tional agent, and (e) surgery. and to have bled from their ulcer in the past. In Continuing the same H2 antagonist for a longer addition, there was no difference in the reduction of period at a higher dose is not tremendously acid secretion by cimetidine. successful. Follow-up of 65 patients with refractory By contrast, Gledhill investigated relatively non- ulcer showed that 60% healed after 4 to 14 (mean responsive patients and found that cimetidine in 7.4) months on cimetidine (at two or three times usual or double dose was less able to suppress the usual dose), while the remaining 40% did not nocturnal gastric secretion compared to unselected even heal after a mean of 9.4 months.' Another duodenal ulcer patients.17 The non-responders to trial found that increasing doses of ranitidine, cimetidine were rendered hypochlorhydric by however, was successful.19 addition of atropine. Additional anticholinergic On present evidence changing to another H2 drug has been found by others18 to enhance the antagonist probably has little more to offer than antisecretory effects of H2 antagonists. More increasing the dose of the current drug. recently a study showed that patients with resistant Conventional doses of cimetidine have less of an ulcers were likely to have an increased basal acid antisecretory effect than ranitidine, while the output, those with a basal acid output greater than newer H2 antagonists famotidine and nizatidine 10mEq/h being unlikely to show ulcer healing on are probably no more effective than ranitidine. In standard dose ranitidine.19 However, these resistant one study20 standard doses of cimetidine and ulcers healed with increasing ranitidine dosage ranitidine produced similar healing rates in patients (mean 650mg/day, range 600 to 900mg/day).'9 with resistant ulcer. However, there is reasonable Formal investigations are awaited to test the evidence that ulcer healing is directly proportional hypothesis that failure to respond to ulcer to the potency of antisecretory effect at night2' and copyright. treatment is due to colonization of the mucosa by therefore trials comparing larger than usual bedtime Campylobacter pylori. The good general response or evening doses H2 antagonists may be of resistant cases to colloidal bismuth (toxic to worthwhile. C. pylori) is the first supportive evidence. Addition of another anti-ulcer drug while continuing the current H2 antagonist at standard or higher doses may bring about greater reduction in Diagnosis of resistant duodenal ulceration gastric acidity. This may be achieved by the addition of an anticholinergic, or high dose http://pmj.bmj.com/ Very occasionally ulcers fail to heal for identifiable antacids.22 23 Such an approach has not reasons. It is likely that some patients simply fail to convincingly been shown to improve healing rates take treatment at all or at the correct dose. In in patients with resistant duodenal ulcers.24 Other addition, endoscopy may have identified rare causes combinations such as an H2 antagonist plus drugs of duodenal ulceration including Crohn's disease, which 'improve mucosal defence', e.g. sucralfate tuberculosis, neoplasia or cytomegalovirus infection and bismuth chelate, have not been formally tested in the immunocompromised patient. The fasting in clinical trials. on September 29, 2021 by guest. Protected plasma gastrin concentration should be measured Another strategy is to change from H2 off treatment and if raised, other investigations to antagonists to one of a number of drugs which exclude the Zollinger-Ellison syndrome should heal ulcers by mechanisms other than reduction follow. Similarly, the serum calcium should be of gastric acid or vice versa. The bismuth chelate, checked to exclude primary hyperparathyroidism. tripotassium dicitrato bismuthate (TDB), acceler- ates ulcer healing and, following healing with TDB, relapse is less frequent than after cimetidine6 or Practical management of the resistant ulcer ranitidine.5 Cimetidine-resistant ulcers appear to respond well to TDB.25'26 Fifty two patients with Advice of a general nature is usually given: to stop resistant duodenal ulcers given cimetidine 1.2g/day, smoking and to discontinue non-steroidal anti- 2 g/day or TDB 480 mg/day, had 4-week healing inflammatory drugs where possible. However rates of 39%, 44% and 82%, respectively.26 After 8 despite medical good intentions we neither know weeks, these figures had risen to 65%, 75% and how many patients with resistant ulcer manage to 94%, respectively. These studies suggest that stop smoking nor whether this manoeuvre results resistant duodenal ulcers may be more responsive Postgrad Med J: first published as 10.1136/pgmj.64.751.369 on 1 May 1988. Downloaded from RESISTANT DUODENAL ULCER 371 to an agent which improves mucosal defences than the antisecretory ones.31 There are no comparative one which reduces gastric acid. There is
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