The effect of gastritis on human gastric alcohol dehydrogenase activity and ethanol metabolism.

BACKGROUND: Gastric mucosal alcohol dehydrogenase (ADH) may decrease the bioavailability of ingested ethanol. Because this enzyme is found in highest concentrations in the superficial gastric mucosa, diffuse abnormalities of this tissue could lead to a decrease in the first pass metabolism of ethanol. METHODS: Thirty-three adult subjects undergoing routine upper gastrointestinal endoscopy had gastric biopsies performed for assessment of gastric histology and the measurement of gastric ADH activity. Twenty of these subjects underwent separate oral dosing and intravenous infusion of ethanol (0.15 g/kg body weight) in order to determine the first pass metabolism, and hence bioavailability, of ethanol. RESULTS: Gastric histology was normal in 10 of the biopsies, showed chronic gastritis alone in 13 and significant glandular atrophy (i.e. atrophic gastritis) in a further 10. Gastric ADH activity in specimens with normal gastric histology was significantly higher than those with chronic gastritis (P = 0.02), and was further decreased in those specimens with significant atrophy (P < 0.00001). However, no correlation was found between gastric ADH activity and the first pass metabolism of ethanol (r = 0.09, P = 0.9). CONCLUSIONS: These results suggest that although gastric ADH activity was decreased in individuals with abnormal gastric mucosa, ethanol bioavailability was not affected by gastric ADH activity. These data support the view that gastric ADH does not play a significant role in the first pass metabolism of alcohol.

Interferon alfa for chronic active hepatitis B. Long term follow-up of 62 patients: outcomes and predictors of response.

OBJECTIVE: To evaluate the response to treatment with interferon alfa and the long term outcome of patients with chronic active hepatitis B. METHODS: Sixty-two patients with chronic active hepatitis B (43 males, 19 females; age range, 10-67 years) who were treated with interferon alfa at Westmead Hospital between 1984 and 1992 were followed up (mean period of follow-up, 44 months). Thirty-nine patients were treated with interferon alfa-2a and 23 with interferon alfa-2b for a mean of 22.5 weeks. Interferon was given three times a week with a dose range of 3-21 million U. We evaluated pretreatment predictors of response (patient's age, sex, ethnic origin, presence of cirrhosis, serum levels of alanine aminotransferase [ALT] and hepatitis B virus DNA [HBV-DNA]) and the effect of dose and type of interferon. RESULTS: Nine patients had a complete response to treatment with interferon alfa (loss of hepatitis B surface antigen), 26 had a partial response (permanently HBV-DNA negative, hepatitis B e antigen to anti-hepatitis Be seroconversion), eight had a transient response and 19 had no response. All patients with a complete response had normal ALT levels at last follow-up. Histological evidence of hepatic inflammation was significantly reduced in responders. A high pretreatment ALT level and a low HBV-DNA titre were both positive predictors of a favourable response. We found no significant difference in the response to different types of interferon or to high or low dose regimens, or in the responses of patients with cirrhosis. CONCLUSION: Treatment with interferon alfa was associated with prolonged suppression of HBV replication in over half these patients and 14% appear to have been cured of the infection. Suppression of HBV replication is associated with sustained abatement of liver disease.

Non-alcoholic steatohepatitis: impaired antipyrine metabolism and hypertriglyceridaemia may be clues to its pathogenesis.

Non-alcoholic steatohepatitis resembles alcoholic liver disease in hepatic morphology but appears to have a different natural history. We sought to assess the nature of non-alcoholic steatohepatitis by a prospective study of its clinical progression and the relationship of biochemical abnormalities to changes in serum lipids among 15 patients with this disorder. In addition, antipyrine clearance (Cl-AP), which reflects hepatic microsomal oxidative capacity, was measured serially. Although initial liver histology included micronodular cirrhosis in five cases and bridging fibrosis in another three, only one patient developed a hepatic complication during 1-10 years (median: 3.7) of follow up. This confirms the relatively benign nature of non-alcoholic steatohepatitis. Moreover, Cl-AP, which was below the normal range in 13 patients, did not change significantly during 10-40 months of follow up. However, compared with other chronic liver diseases, the reduced Cl-AP was disproportionately low relative to the uniformly normal serum albumin concentration and other indices of hepatic metabolic function. This is consistent with selective impairment of endoplasmic reticular drug oxidizing enzymes. Hyperlipidaemia was present in 11 patients. In three of these, diet-induced correction of serum triglyceride elevation was associated with reduction of hepatocellular damage as indicated by serum enzyme levels. A hypothesis that unites these and earlier findings is that release of cytokines may occur in non-alcoholic steatohepatitis and produce accumulation of free fatty acids in the liver, leading to focal necro-inflammatory lesions and the destruction or down-regulation of cytochrome P450.

The role of fibre optics in gastroenterology.

Diagnostic fibre optic endoscopy has a well established role in clinical gastroenterology. The authors highlight the expanding therapeutic applications of this technology.