Background/aims: Data from previous studies on gastric acid secretion in patients with hepatic cirrhosis are controversial, due, at least in part, to the possible interference of liver failure and altered gastric mucosal microcirculation on the pharmacological action of the substances used to stimulate the parietal cell. For this reason, we wished to investigate the circadian pattern of gastric acidity by means of continuous 24-hour pH monitoring, which permits measurement of pH fluctuations in a nearly physiological manner and does not require any pharmacological stimulus.
Methods: Forty-nine patients with liver cirrhosis of different aetiology were recruited for this study. They underwent 24-hour gastric pH-metry with an electrode positioned in the gastric corpus, and their pattern of gastric acidity was compared with that of 49 healthy subjects, matched for age and sex. In a subgroup of 31 patients with cirrhosis, antral pH was recorded in addition to body pH in order to assess whether there are regional differences in gastric acidity.
Results: The circadian, daytime and nocturnal gastric acidity in patients with cirrhosis was significantly lower (p < 0.05-0.001) than that of controls. In the 31 patients studied with two electrodes, antral pH was higher (p < 0.05) than body pH only during the night. The prevalence of Helicobacter pylori infection was rather low (42%) in our patients.
Conclusions: There is a marked hypoacidity over the circadian cycle in patients with cirrhosis compared to controls, and the greatest difference between them is visible during the nocturnal hours. Also, in patients with liver cirrhosis the pH in the antrum is higher than that in the body of the stomach during the night for reasons that need to be elucidated.