Clinical usefulness of gastric-juice analysis in 2007: the stone that the builders rejected has become the cornerstone.

BACKGROUND: Gastric juice is usually discarded during upper-GI endoscopy. OBJECTIVE: By using a novel device, the Mt 21-42, we evaluated the potential of this important organic fluid in clinical practice, exploring its contribution to the diagnosis of Helicobacter pylori infection and atrophic gastritis of the oxyntic mucosa (AGOM). DESIGN AND PATIENTS: A multicenter study (17,907 patients; 10 endoscopy units) estimated the frequency of diagnosis of AGOM and H pylori infection in routine endoscopic practice. A prospective study (216 patients) at 1 of these units aimed to determine the real prevalence of these conditions and the possible benefits of gastric juice analysis. We considered gastric juice pH and ammonium concentration, endoscopic and histologic features, serologic parameters for atrophy and H pylori, gastric acid secretion, and costs. RESULTS: We found that H pylori infection and, even more markedly, AGOM were greatly underdiagnosed in routine endoscopic practice (20.1% and 0.8% vs 49.1% and 12.5% in the prospective study, respectively), because of the intrinsic limitations of the conventional tests and lack/inappropriateness of biopsy planning. Gastric-juice analysis proved to be a cheap, simple, and effective way to prevent such underdiagnosis and allowed detection of atrophic gastritis and H pylori in 96% and 98% of cases, and saved costs (cost-effectiveness ratio 209 vs 274-5047). CONCLUSIONS: Gastric juice provided a valuable source of clinicopathologic information that, properly analyzed, allowed detection of the main risk factors for gastric cancer (H pylori and atrophic gastritis), overcoming the diagnostic limitations associated with these conditions and also producing time and cost savings.

Mt 21-42: development and validation of an automatic device proposed for the endoscopic diagnosis of Helicobacter pylori infection and atrophic gastritis.

BACKGROUND: Gastric juice may give important clinico-pathological information, but measurements in this medium are difficult. In this study we present and validate an innovative device (Mt 21-42) performing gastric juice analyses during endoscopy and proposed for the endoscopic diagnosis of Helicobacter pylori infection and hypo/achlorhydria. METHODS: Analyses on both aqueous solutions (80 pH buffer + 120 ammonium chloride samples) and human gastric juice were carried out to assess the measuring performance of Mt 21-42 on the ideal and real matrix, respectively. Matrix spike and manipulation tests were also performed to investigate the matrix effect of gastric juice and to evaluate the consequences of its manipulation on the measurements. Furthermore, preliminary clinical tests were performed to evaluate the clinical potentiality of the device. RESULTS: Mt 21-42 showed a good measuring performance on ideal matrix (coefficient variation: pH = 1.3%, ammonium = 2.1%) and real matrix (coefficient variation: pH = 1.2%, ammonium = 1.9%). Analyses on gastric juice excluded a substantial matrix effect (percent recovery =96.5-98.7%) but demonstrated a significant influence of manipulation procedures (p < 0.05). CONCLUSIONS: Human gastric juice does not have a substantial matrix effect for pH and ammonium determination, but its manipulation may affect the measurement of these components. Mt 21-42 represents a precise instrument for the measurement of gastric juice and a potential precious tool for the endoscopic detection of H. pylori infection and hypo/achlorhydric conditions.