Assessment of gastric acidity by short-duration intragastric pH-monitoring with standardised breakfast in functional and some other dyspepsias

Abstract

Introduction: Preliminary assessment of gastric secretion in the treatment of organic and functional dyspepsia may offer advantages over the empirical administration of proton pump inhibitors suggested by most clinical guidelines.

Aim: To develop a simplified pH-metric test with standardised meal, and on its basis to perform an assessment of the functional state of gastric secretion in the most common dyspepsias.

Material and methods: Serum pepsinogen 1 and 2 were used for reference. Intragastric pH-monitoring was performed during 45 min in basal phase and 135 min after provocative breakfast (507 kcal, 100 mg caffeine). Consecutive adults enrolled in the study were divided into groups: 1 - "Non-dyspeptic" - 30 persons; 2 - "Duodenal peptic ulcer" - 13; 3 - "GERD" - 82; and 4 - "Functional dyspepsia" - 125 patients.

Results: There was a moderate association between concentration of pepsinogen-1 and parameters of pH-monitoring. The best correlation coefficients were for the nadir pH in basal conditions and the time of acid neutralisation > 3.5 after the meal - r = -0.534 and r = -0.541, respectively (p < 0.0001). Using these two parameters we considered discriminants for four patterns of acidity. Proposed criteria of Hipo-anacidity included an absence of active secretion of hydrochloric acid in basal (pHmin > 5) and postprandial phases, with the achievement of stable pH < 3.5 after 80 min from meal time. They showed sensitivity 88.9% and specificity 100%. In cases of a detected pattern of hyperacidity, these parameters were 80% and 66.67%, respectively. According to the prevalence of hyperacidic cases, the groups were ranked in the following order: duodenal ulcer (76.9%) - GERD (51.1%) - functional dyspepsia (40.8%) - non-dyspeptic (19.0%).

Conclusions: Acid production is increased among patients with functional dyspepsia. There is a small number of patients with functional dyspepsia (12.1%) with hypochlorhydria due to atrophic gastritis. The latter was independently associated with age > 50 years (OR = 20.139), symptoms of postprandial distress-syndrome (OR = 9.821), and signs of atrophy (OR = 5.914) after conventional endoscopy.

Keywords: atrophic gastritis; dyspepsia; intragastric pH-metry; pepsinogens.

Figure 1

Design of 200-minute gastric pH-monitoring with provocative breakfast and sample pH-tracing. Marks pH1, pH2, and pH3 depict minimal value in basal and two postprandial phases; t1 – time of acid-neutralisation, t2 – time after breakfast until reaching a threshold pH < 3.5

Figure 2

The distribution of patients by patterns of gastric acidity after a 200-minute intragastric pH-monitoring with a standardised breakfast GERD – gastroesophageal reflux disease.