1127. Role of gastric acid suppression in the treatment of gastro-oesophageal reflux disease.
Gastro-oesophageal reflux disease is a common condition with a complex pathophysiology. Despite the spectrum of abnormalities, gastric acid has a central role in mucosal damage, and the mainstay of medical treatment is suppression of gastric acid secretion. The results of antisecretory treatment as assessed by endoscopic healing are reviewed. H2 receptor antagonists give more rapid symptom relief than placebo and can produce endoscopic improvement in 31-88% of cases depending on the severity of oesophagitis. Complete healing, however, is seen only in 27-45% of patients and these have mainly grades I-II disease. Improved healing rates can be obtained by increasing the degree of acid suppression or the length of treatment. The addition of a prokinetic agent may be beneficial. Omeprazole heals 67-92% of patients overall and although most successful in the lower grades of oesophagitis, can also heal 48-62% of patients with grade IV disease. The degree and rate of healing seem to be related to the reduction in oesophageal acid exposure and thus may correlate with the degree and duration of acid suppression over 24 hours obtained by the various treatments. The underlying pathophysiology is unchanged, however, and long term treatment may be needed to maintain remission.
1128. Overview of screening and management of familial adenomatous polyposis.
The rarity of familial adenomatous polyposis (FAP) means that many clinicians may be unaware of the major advances that have taken place in screening for the condition over the past five years. This review is not only to document the current scene but also to give details of those involved in establishing registries throughout the country. FAP is a hereditary disorder which carries with it almost a 100% risk of colorectal cancer. The aim of screening is to detect gene carriers before they present with symptoms attributable to colonic polyps. In this way the incidence of colorectal cancer can be greatly reduced. The use of gene probes to identify patients with FAP is in its infancy but in selected pedigrees gene carriers can be identified using a venous blood sample. The recognition that congenital hypertrophy of the retinal pigment epithelium is an extracolonic manifestation of FAP in most pedigrees allows non-invasive ophthalmological screening of relatives at risk. The combination of these new screening methods with an effective regional registry for FAP can increase the number of patients detected by screening rather than by symptoms. This facilitates appropriate prophylactic surgery and reduces mortality related to colorectal cancer.
1130. Small intestinal length: a factor essential for gut adaptation.
Changes in small intestinal structure, cytokinetics, and function are dynamic ways in which the gut adapts to diet, disease, and damage. Adequate length provides a static 'reserve' permitting an immediate response to pathophysiological changes. The length of the small intestine from conception to adulthood using data taken from eight published reports of necropsy measurement of 1010 guts is described. Mean length at 20 weeks' gestation was 125 cm, at 30 weeks' 200 cm, at term 275 cm, at 1 year 380 cm, at 5 years 450 cm, at 10 years 500 cm, and at 20 years 575 cm. Prenatal small intestinal growth exceeded that of body length according to the law: small intestinal length alpha body length to the power 4/3. After birth there was a noticeable deceleration: small intestinal length alpha body length to the power 1/2. The coefficient of variation of small intestinal length postnatally was 24%, sixfold greater than for body length. The rapid prenatal small intestinal growth rate ensures that the mature newborn has adequate small intestine to meet postnatal nutritional demands, but handicaps the preterm infant who undergoes intestinal resection. The wide variation in lengths suggests a 'surplus' surface area that is immediately available to respond, independent of dynamic mucosal changes, to fluctuations in food availability, local intestinal disease, damage, rapid transit, and resection.
1132. Alkaline reflux oesophagitis.
Duodenal and gastric contents do reflux into the oesophagus and acid alone certainly causes oesophageal damage which will be worsened by pepsin. In the patient who has undergone gastrectomy duodenal secretions may also be harmful. There is evidence that when the two mix there may be a toxic synergism, leading to mucosal disruption and intracellular damage to oesophageal cells which produces the clinical picture of reflux oesophagitis, with or without symptoms. Clear evidence of the toxicity of duodenal refluxate in humans is lacking, but the ability to measure bile and acid reflux continuously, together with a method of detecting oesophageal damage at a cellular level should help to solve this long debated problem.
1133. Appropriateness of cholecystectomy in the United Kingdom--a consensus panel approach.
A consensus development approach was used to assess the extent to which doctors in the UK agreed about the appropriate indications for cholecystectomy. Two panels, one composed entirely of surgeons and one containing a mix of relevant specialists, were asked to rate a series of possible indications. A consensus was achieved for 61% (surgical panel) and 67% (mixed panel) of indications considered. The surgical panel considered more indications as being appropriate for cholecystectomy (29% v 13%) and fewer indications as being inappropriate (27% v 50%) than the mixed panel. For between one third and a half of all indications, the panels were unable to reach agreement, partly as a result of differences in views as to the role of endoscopic sphincterotomy.
1134. Ursodeoxycholic acid in chronic liver disease.
The hydrophilic bile acid ursodeoxycholic acid has recently been shown to reduce biochemical markers of both cholestasis and hepatocellular damage in patients with chronic liver diseases. The most compelling evidence available is for chronic cholestatic liver diseases, in particular primary biliary cirrhosis, primary sclerosing cholangitis, and cholestasis associated with cystic fibrosis. The effects may be less beneficial in patients with advanced liver disease from these conditions. Data from placebo controlled trials are now available in support of earlier uncontrolled observations, but it is not yet clear whether short term benefit results in an improvement in longterm prognosis. The mechanism of action of the compound seems to reside in its displacement of toxic hydrophobic bile acids from both the bile acid pool and hepatocellular membranes. There may be an independent effect on bile flow, which could be of particular importance in cystic fibrosis, and possibly an effect on the immune system. Ursodeoxycholic acid should now be regarded as occupying a central place in the medical management of chronic cholestatic liver diseases, in particular primary biliary cirrhosis, because it improves cholestasis and reduces hepatocellular damage and it is not toxic. Research should now be targeted on whether treatment with ursodeoxycholic acid, initiated early in cholestatic liver conditions, improves the long-term outcome.
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