The upper gastrointestinal tract in chronic alcoholics

Abstract: Background: Gastrointestinal symptoms such as dyspepsia, diarrhoea, and nausea are often seen in alcoholics. The causes are not clear. The stomach and upper small intestine are exposed to high alcohol concentrations. Yet, the majority of alcohol abusers do not exhibit macroscopic abnormalities at upper gastrointestinal endoscopy, although histological and electron microscopic (SEM) changes have been described. However, there are only scanty and contradictory data on this subject so far. Aim: In order to extend our knowledge in this field, we have studied a fairly large number of chronic alcoholics with respect to GI symptoms and endoscopic findings. Moreover we also explored the occurrence of Helicobacter pylori and mucosal bacterial growth, electron microscopical changes in duodenal mucosal morphology and induction of gamma-glutamyl transferase (GGT), intestinal alkaline phosphatase (IAP) and neuropeptides in the duodenal mucosa. Materials and methods: Twenty-four chronic alcoholics who were admitted to hospital for detoxification were investigated using an interview, upper gastrointestinal endoscopy with biopsies, and laboratory tests. The mean daily consumption of alcohol during the weeks before admission was 338 g/day (102-680). The control groups consisted of 12–33 patients referred for upper gastrointestinal endoscopy because of dyspepsia of the ulcer or reflux type, but who felt healthy otherwise. In addition, an interview was carried out as well as laboratory tests including serum CDT and serum GGT. The alcohol consumption was less than 40 g/week. Results: Twenty-one of 24 alcoholics had gastrointestinal symptoms on examination: 15 had abdominal pain/dyspepsia, 12 had diarrhoea, and 6 had nausea. There were not more patients with H. pylori infection in the alcohol group compared to controls and prevalence studies. Endoscopy showed no difference between the groups. Histology showed a slightly reduced villus index in duodenal biopsies, as well as ultrastructural changes (SEM). There were significantly more bacteria in the gastric mucosa in alcoholics than in controls (p<0.05). IAP and GGT levels were significantly higher in duodenal biopsies in the alcohol group (p=0.001, p<0.0001). The density of all the peptidergic nerve fibres in the duodenal mucosa exhibited a moderate general increase, but none of the peptides was selectively and strongly influenced. The numbers of glucagon and GIP cells in the duodenal mucosa were slightly increased in the alcohol group (p=0.02). Summary and conclusion: Chronic alcoholics often have gastrointestinal symptoms. They frequently exhibit mucosal bacterial overgrowth. Electron microscopic morphological changes are commonly found. GGT and IAP in the duodenal mucosa are increased. An alteration in the peptidergic nerve system as well as in some endocrine cells could be observed. Thus, in spite of scarce endoscopic findings in the upper GI tract, chronic alcoholics do show definite alterations in several respects as mentioned above.