RE.GA.IN.: the Real-world Gastritis Initiative–updating the updates

Abstract

At the end of the last century, a far-sighted ‘working party’ held in Sydney, Australia addressed the clinicopathological issues related to gastric inflammatory diseases. A few years later, an international conference held in Houston, Texas, USA critically updated the seminal Sydney classification. In line with these initiatives, Kyoto Global Consensus Report, flanked by the Maastricht-Florence conferences, added new clinical evidence to the gastritis clinicopathological puzzle.The most relevant topics related to the gastric inflammatory diseases have been addressed by the Real-world Gastritis Initiative (RE.GA.IN.), from disease definitions to the clinical diagnosis and prognosis. This paper reports the conclusions of the RE.GA.IN. consensus process, which culminated in Venice in November 2022 after more than 8 months of intense global scientific deliberations. A forum of gastritis scholars from five continents participated in the multidisciplinary RE.GA.IN. consensus. After lively debates on the most controversial aspects of the gastritis spectrum, the RE.GA.IN. Faculty amalgamated complementary knowledge to distil patient-centred, evidence-based statements to assist health professionals in their real-world clinical practice. The sections of this report focus on: the epidemiology of gastritis;Helicobacter pylorias dominant aetiology of environmental gastritis and as the most important determinant of the gastric oncogenetic field; the evolving knowledge on gastric autoimmunity; the clinicopathological relevance of gastric microbiota; the new diagnostic horizons of endoscopy; and the clinical priority of histologically reporting gastritis in terms of staging. The ultimate goal of RE.GA.IN. was and remains the promotion of further improvement in the clinical management of patients with gastritis.

Autoimmune Gastritis and Hypochlorhydria: Known Concepts from a New Perspective

“…In contrast, other recent prospective studies reported an increased incidence of GC and high-grade dysplasia in a long-term follow-up in Hp-negative patients with AAG [111,112]. Methodological issues and different study populations, such as studies being limited to PA or lacking exclusion of Hp infection or inclusion of patients at a pre-atrophic stage, are probably responsible for the different GC risk estimates in AAG [45,113]. In any case, this debate has raised two significant issues: the need to define precise diagnostic criteria for AAG and specific criteria for excluding current or previous Hp infection in patients with corpus-restricted CAG [113].…”

“…However, IFAs are highly specific but poorly sensitive [10,44]. Several studies suggested that any type of atrophy can be diagnosed by dosing serum gastrin and pepsinogen (Pg) I and II and determining the PgI/II ratio [45][46][47][48]. In AAG patients, the PgI/PgII ratio is low because PgI is no longer produced by the oxyntic glands of the gastric body.…”

“…However, data in this field are scarce, and the role of the gastric microbiota in gastric carcinogenesis is still debated. Some studies have highlighted an increase in bacterial diversity in the gastric microbiota of patients with GC [45,95]; in particular, there has been an increase in oral taxa such as Streptococcus, Staphylococcus, Lactococcus, Bacillus, Prevotella, Veillonella and Leptotrichia. Furthermore, as mentioned earlier, the prevalence of streptococci, which belong to the oral microbiota, has been found in AAG.…”

Helicobacter pylori Infection in Patients with Gastric Cancer: A 2024 Update

“…3. It is unknown how additional factors, in the absence of H. pylori or after its eradication, contribute to the epidemiology of chronic gastritis [ 62 ]. It has also been demonstrated that a fraction of H. pylori -infected children, especially those harboring virulent strains, present premalignant lesions.…”