[Euricterus. A European database on icterus with emphasis on the Danish contribution]

Clinical and biochemical data were collected prospectively from 8032 jaundiced patients to form a database as part of a EU-supported project on computer-aided diagnosis. Patients were recruited prospectively from centres in all EU-countries and some other countries as well. Five hundred and twenty-eight jaundiced patients were collected from four centres in Denmark. Alcoholic cirrhosis, acute alcoholic liver disease and malignancy of the pancreas or the biliary tract were more common in the Danish data base: 49% of cases in Denmark as compared to 30% of cases in the international database. Viral hepatitis was underrepresented in Denmark, 16% as compared to 23% in the international group. A crude Bayesian diagnostic programme on the total database with 17 diagnostic groups achieved 63% accuracy. For the 528 Danish cases the diagnostic accuracy was 64% when the European data base was used, whereas it increased to 81% when only the Danish data base was taken as basis for the calculations. In conclusion, we found a drop in diagnostic accuracy for the Danish patients when using the large European data base instead of the national one.

[Randomized trial and meta-analysis of somatostatin versus placebo in bleeding esophageal varices]

We studied whether somatostatin or its derivative, octreotide, is more effective than placebo in the treatment of bleeding oesophageal varices in a randomised, double-blind trial and a meta-analysis with blinded data analysis and manuscript writing. Patients suspected of bleeding from oesophageal varices and of having cirrhosis of the liver were eligible. Eighty-six patients were randomised; 16 died in each group within six weeks (95% confidence interval (CI) for difference in mortality -19% to 22%). There were no differences between somatostatin and placebo in median number of blood transfusions (8 vs 5, p = 0.07, CI 0 to 4 transfusions) or in numbers of patients who needed balloon tamponade (16 vs 13, p = 0.54, CI -11% to 28%). In a meta-analysis of three trials, involving 290 patients, somatostatin had no effect on survival compared with placebo (p = 0.59, odds ratio 1.16, CI 0.67 to 2.01). For blood transfusions and use of balloon tamponade there was heterogeneity between the trials with no convincing evidence in favour of somatostatin.

Somatostatin v placebo in bleeding oesophageal varices: randomised trial and meta-analysis

OBJECTIVE

To study whether somatostatin or its derivative octreotide is more effective than placebo for treating bleeding oesophageal varices.

METHODS

Randomised, double blind trial and meta-analysis with blinded analysis of data and writing of manuscripts.

SETTING

Departments of medical and surgical gastroenterology in Copenhagen.

SUBJECTS

Patients suspected of bleeding from oesophageal varices and of having cirrhosis of the liver.

MAIN OUTCOME MEASURES

Survival, number of blood transfusions, and use of Sengstaken-Blakemore tube.

RESULTS

86 patients were randomised; in each group 16 died within six weeks (95% confidence interval for difference in mortality--19% to 22%). There were no differences between those treated with somatostatin or placebo in median number of blood transfusions (8 v 5, P = 0.07, 0 to 4 transfusions) or in numbers of patients who needed balloon tamponade (16 v 13, P = 0.54, -11% to 28%). In a meta-analysis of three trials involving 290 patients somatostatin had no effect on survival compared with placebo (P = 0.59, odds ratio 1.16; 0.67 to 2.01). For blood transfusions and use of balloon tamponade there was heterogeneity between the trials with no convincing evidence in favour of somatostatin. No placebo controlled trials have been performed with octreotide.

CONCLUSION

Within the limited power of this study and meta-analysis we were unable to show a clinical benefit of somatostatin in the emergency treatment of bleeding oesophageal varices.

Colonic fermentation of ispaghula, wheat bran, glucose, and albumin to short-chain fatty acids and ammonia evaluated in vitro in 50 subjects

The production of short-chain fatty acids and ammonia was measured in 16.6% fecal homogenates from 50 subjects incubated at 37 degrees C for 6 and 24 hours. All 50 homogenates produced ammonia and short-chain fatty acids of any chain length (C2-C5). Incubation for 24 hours with dietary fiber (ispaghula husk or wheat bran), albumin, or glucose (10 mg/mL) increased the short-chain fatty acid production (43.6 +/- 2.8, 45.4 +/- 2.0, 60.3 +/- 3.2, and 65.8 +/- 3.1 mmol/L, respectively) compared with controls (21.4 +/- 1.3 mmol/L). The degradation of different substrates was associated with the production of different amounts of ammonia and short-chain fatty acids. Ispaghula, wheat bran, albumin, and glucose were fermented to acetate (> 2 mmol/L; 24-hour incubations) in 86%, 96%, 98%, and 98% of the homogenates, to propionate in 80%, 76%, 100%, and 68%, and to butyrate in 32%, 94%, 88%, and 54% of the homogenates, respectively. Isobutyrate, valerate, and isovalerate were produced from albumin in all (100%) of the homogenates, but only in 2 to 4% of the homogenates incubated with ispaghula or glucose. Ammonia was always (100%) produced after the addition of albumin and always (98%) consumed (assimilated) when glucose was fermented. Surgery (sigmoid or right- or left-sided colonic resection) did not change the pattern of ammonia and short-chain fatty acid production from these substrates. This study suggests that the different colonic flora from a large number of subjects share general biochemical characteristics, which metabolize different substrates to specific patterns of ammonia and short-chain fatty acids.

Colonic fermentation to short-chain fatty acids is decreased in antibiotic-associated diarrhea

To elucidate the pathogenesis of antibiotic-associated diarrhea, colonic carbohydrate fermentation was investigated in three groups of subjects--a group of controls, a group of patients with antibiotic-associated diarrhea, and a group of patients receiving antibiotic therapy without diarrhea. Compared with controls, the colonic fermentation was markedly impaired in patients with antibiotic-associated diarrhea reflected by both very low concentrations (22.1 vs. 59.5 mmol/L; P less than 0.01) and production rates of short-chain fatty acids. In the group of patients without diarrhea, the effect on the colonic fermentation was dependent on the antibiotic administered. Penicillin and pivampicillin PO did not reduce the concentrations (69.9 and 66.7 mmol/L, respectively) or production rates. Dicloxacillin, erythromycin, and combined IV treatment with ampicillin, netilmicin, and metronidazole reduced both concentrations (27.1, 38.2, and 18.8 mmol/L; P less than 0.01) and production rates of short-chain fatty acids to levels seen in patients with diarrhea. L-Lactate and D-lactate concentrations were normal in all patients (less than 5 mmol/L), but lactate production was reduced in the patients who had reduced production of short-chain fatty acids, including patients with diarrhea. Thus, antibiotic-associated diarrhea was always related to reduced fecal concentrations and production rates of short-chain fatty acids and production rates of lactate. These results suggest that the antibiotic-associated diarrhea might be secondary to impaired colonic fermentation in otherwise disposed subjects, resulting in accumulation of luminal carbohydrate and/or decreased short-chain fatty acid-stimulated sodium and water absorption.

Colonic fermentation of dietary fibre to short chain fatty acids in patients with adenomatous polyps and colonic cancer

Short chain (C2-C6) fatty acids are produced in the colon through bacterial fermentation of mainly dietary fibre. Butyrate (C4) possesses antineoplastic effects on human colon carcinoma cells, and epidemiological studies indicate that high fibre diets may reduce the incidence of colorectal cancer. The role of dietary fibre during colorectal carcinogenesis might therefore be related to its fermentation to butyrate. Faecal concentrations of total short chain fatty acids and concentrations and ratios of the individual C2-C6 fatty acids did not differ between 16 healthy controls, 17 patients with colonic adenomas, and 17 patients with colonic cancer. Comparison of the molar production velocities (mmol/l.hour) of total and individual short chain fatty acids from glucose, ispagula, wheat bran, and albumin in six and 24 hour faecal incubations showed no differences. The ratio of butyrate production to total short chain fatty acid production from fibre, however, was reduced in patients with colonic cancer and adenomas compared with healthy controls (ispagula, six hours: 6.4, 7.6, and 11.5% respectively, p = 0.005 and 24 hour: 9.1, 9.9, and 15.4%, p = 0.002; wheat bran, six hours: 9.9, 10.2, and 14.7% respectively, p = 0.06 and 24 hours: 15.1, 16.8, and 21.0%, p = 0.01). It may be that the low ratios of colonic butyrate formation combined with low fibre diets increase the risk of colonic neoplasia.

The degradation of amino acids, proteins, and blood to short-chain fatty acids in colon is prevented by lactulose

Short-chain (C2-C5) fatty acids account for 60%-70% of the anions in the colon. Acetate (C2) is nontoxic in contrast to C(3)4-C5 fatty acids (propionate, butyrate, isobutyrate, valerate, and isovalerate), which induce coma in animals and may be important in the pathogenesis of hepatic coma in humans. An in-vitro fecal incubation system was used to map out short-chain fatty acid production in the presence of lactulose, amino acids, albumin, or blood. Albumin and blood increased production of all C2-C5 fatty acids. In contrast, lactulose was converted to acetate only and increased fecal acidity. The degradation of amino acids, albumin, and blood to short-chain fatty acids was completely inhibited by 10-25 mM lactulose. This was caused mainly by the acidifying effect of lactulose. pH-independent inhibition of blood and amino acid degradation to short-chain fatty acids required concentrations of lactulose exceeding 50-100 mM. Thus, the effect of lactulose in the treatment of hepatic coma may be related to its rapid fermentation into organic acids at rates exceeding colonic buffering capacity. This probably reduces formation of toxic fatty acids and ammonia from amino acids, polypeptides, and blood in the colon.