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

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 pylori as 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.

Gut inflammation induced by drugs: Can pathology help to differentiate from inflammatory bowel disease?

Drug‐induced mucosal injury (DIMI) in the gastrointestinal tract is important to recognise, partly because cessation of the culprit agent alone may result in resolution of symptoms. An ever‐growing list of medications, including newer immunotherapeutic agents and targeted therapies, can cause gastrointestinal inflammation of varying severity. However, the diagnosis of DIMI is challenging, as a single drug can induce a variety of histopathological patterns of injury including acute colitis, chronic colitis, microscopic colitis, apoptotic colopathy, and ischaemic‐type colitis. An additional consideration is the potential clinical, endoscopic and histological overlap of DIMI with gastrointestinal mucosal injury secondary to other entities such as inflammatory bowel disease (IBD). We discuss DIMI of the gastrointestinal tract with an emphasis on histological patterns that mimic IBD, histological features which may distinguish the two entities, and the diagnostic role and limitations of the pathologist.

ECCO Topical Review on Clinicopathological Spectrum and Differential Diagnosis of Inflammatory Bowel Disease

INTRODUCTION

Many diseases can imitate inflammatory bowel disease [IBD] clinically and pathologically. This review outlines the differential diagnosis of IBD and discusses morphological pointers and ancillary techniques that assist with the distinction between IBD and its mimics.

METHODS

European Crohn's and Colitis Organisation [ECCO] Topical Reviews are the result of an expert consensus. For this review, ECCO announced an open call to its members and formed three working groups [WGs] to study clinical aspects, pathological considerations, and the value of ancillary techniques. All WGs performed a systematic literature search.

RESULTS

Each WG produced a draft text and drew up provisional Current Practice Position [CPP] statements that highlighted the most important conclusions. Discussions and a preliminary voting round took place, with subsequent revision of CPP statements and text and a further meeting to agree on final statements.

CONCLUSIONS

Clinicians and pathologists encounter a wide variety of mimics of IBD, including infection, drug-induced disease, vascular disorders, diverticular disease, diversion proctocolitis, radiation damage, and immune disorders. Reliable distinction requires a multidisciplinary approach.

Pathologist's approach to paediatric and neonatal eosinophilic gastrointestinal disorders

Children are not simply miniature adults. The evaluation of their gastrointestinal disorders is therefore different from that in full-grown adults and requires a particular clinical/pathologic approach.

Different studies have tried to assess the normal eosinophil distribution in the gastrointestinal tract in adults while very few studies have investigated the paediatric population, consequently complicating the pathologist’s ability in identifying an abnormal number of eosinophils in this setting of patients.

When evaluating gastrointestinal tract biopsies with eosinophilia, eosinophilic count must be considered along with other histological features like eosinophil distribution in the gastrointestinal wall, their degranulation, cryptitis and crypt abscesses, other accompanying inflammatory cells, apoptotic bodies, foreign material or microorganisms; these findings, although rarely specific, may be a useful aid for diagnosis.

Reports should not include a diagnosis of primary eosinophilic gastrointestinal disorders (EoGID) if clinical data and test results do not rule out other forms of gastrointestinal eosinophilia. A more descriptive definition like “with eosinophilic pattern” should be favoured over a specific diagnosis of “eosinophilic disorder” in order to avoid potential confusion between different entities.

Histopathology of Non-IBD Colitis. A practical approach from the Italian Group for the study of the gastrointestinal tract (GIPAD)

Non-IBD colitides (NIBDC) are intestinal diseases clinically and endoscopically overlapping with Inflammatory Bowel Diseases (IBD), sometimes with a similar histological picture. NIBDC include entities such as infectious colitis, ischemic colitis, pseudomembranous colitis, eosinophilic colitis, autoimmune enterocolitis, segmental colitis associated with diverticulosis, drug-induced colitis, radiation-induced colitis, diversion colitis, and microscopic colitis, this last including two entities: collagenous and lymphocytic colitis. The knowledge of the most useful histological features and the main clinical data for each entity is mandatory in daily clinical practice, for correct pathological diagnosis and clinical management.

Iron Pill-Induced Gastritis in the Paediatric Population

Iron is the most common trace mineral in the body. The effects of iatrogenic iron pill-induced gastritis (IPIG) at therapeutic levels are underreported and underappreciated in the paediatric population. Herein, we report a case of an 11-year-old boy presenting with increasing epigastric pain and refusing oral intake secondary to iron pill tablets. We report only the second confirmed case of a paediatric patient with IPIG in the peer-reviewed literature.

Gastric Siderosis and Ulceration from Intravenous Iron Supplementation Manifesting as Chronic Upper Gastrointestinal Bleeding: A Case Report and Review of the Literature

Iron deficiency is the most common etiology of anemia worldwide and is often managed with varying methods of iron supplementation. Although rare, oral iron supplementation can perpetuate iron deficiency anemia by causing gastric ulceration and upper gastrointestinal bleeding in high-risk populations. However, this complication has not been previously described with intravenous iron supplementation. We present a case of a 63-year-old male with severe iron deficiency anemia on biweekly intravenous iron infusions and weekly packed red blood cell transfusions who presented with melena over several months. Upper endoscopy demonstrated a clean-based gastric body ulcer and nonbleeding gastric varices. Histology of the gastric ulcer was suggestive of iron-induced gastric mucosal injury. This case demonstrates that frequent utilization of intravenous iron and packed red blood cell transfusions may predispose certain patients to the development of iron-induced gastritis and ulceration.

A rare case of iron-pill induced gastritis in a female teenager: A case report and a review of the literature

RATIONALE

The treatment of iron-deficiency anemia with oral iron supplements can present side-effects on the GI tract mucosa including necrosis, ulceration, or ischemia. The particular endoscopic findings and the histopathological exam will establish the diagnosis of erosive gastritis with iron deposits in the gastric mucosa.

PATIENT CONCERNS

We present the case of a 14-year-old female admitted in our clinic for upper digestive hemorrhage, nausea, melena, and abdominal pain. Her personal history revealed iron deficiency anemia receiving oral iron supplements for approximately 2 weeks.

DIAGNOSIS

The laboratory tests at the moment of admission pointed out anemia, increased level of serum iron, increased liver transaminases, a decreased level of ferritin, but with normal levels of both total iron-binding capacity and transferrin.

INTERVENTIONS

The eso-gastro-duodenoscopy revealed multiple brown deposits on the surface of the gastric mucosa and multiple hemorrhagic lesions, under the aspect of erosions all over the gastric mucosa, but more severe in the antral part, and the histopathological exam confirmed the presence of iron deposits at this level.

CONCLUSION

Iron-pill induced gastritis is a rare, under-diagnosed entity that can be present even at pediatric ages with potential severe clinical impact.

The Impact of New Technologic and Molecular Advances in the Daily Practice of Gastrointestinal and Hepatobiliary Pathology

The practice of anatomic pathology, and of gastrointestinal pathology in particular, has been dramatically transformed in the past decade. In addition to the multitude of diseases, syndromes, and clinical entities encountered in daily clinical practice, the increasing integration of new technologic and molecular advances into the field of gastroenterology is occurring at a fast pace. Application of these advances has challenged pathologists to correlate newer methodologies with existing morphologic criteria, which in many instances still provide the gold standard for diagnosis. This review describes the impact of new technologic and molecular advances on the daily practice of gastrointestinal and hepatobiliary pathology. We discuss new drugs that can affect the gastrointestinal tract and liver, new endoluminal techniques, new molecular tests that are often performed reflexively, new imaging techniques for evaluating hepatocellular carcinoma, and modified approaches to the gross and histologic assessment of tissues that have been exposed to neoadjuvant therapies.

Gastric siderosis: An under-recognized and rare clinical entity

The increased deposition of iron in gastric mucosa is known as gastric siderosis. It is believed that the only regulated step of the iron metabolism cycle occurs during absorption in the small intestine. Once this system becomes overwhelmed due to either local or widespread iron levels, then iron can be absorbed very quickly by a passive concentration-dependent mechanism. This excess iron is initially stored in the liver but later can be found in the pancreas, heart and joints. Excess iron is not expected to deposit in the gastric mucosa. This gastric deposition has been found in association with hemochromatosis, oral iron medications, alcohol abuse, blood transfusions, hepatic cirrhosis and spontaneous portacaval shunt with esophageal varices. The precise mechanism of this iron deposition in gastric epithelial and stromal cells is still not well understood; thus, identification of iron in gastric mucosa raises many questions. On histology, the pattern of deposition is variable, and recognition of the pattern is often useful to choose the appropriate workup for the patient and to diagnose and possibly treat the cause of iron overload. In this article, we have described a well-referenced review of this rare clinical entity with different histological patterns, diagnostic tests and the clinical significance of the different patterns of iron deposition.

Iatrogenic pathology of the intestines

Many drugs and chemical agents can cause enteritis and colitis, producing clinical gastrointestinal side effects, the most common of which are diarrhoea, constipation, nausea and vomiting. Significant histological overlap exists between some patterns of medication or chemical injury and various disease entities. A particular medication may cause multiple patterns of injury and may mimic common entities such as coeliac disease, Crohn's disease, infectious enteritis and colitis. Thus, given the common absence of specific histopathological features, the diagnosis often relies upon thorough clinicopathological correlation. This review concentrates on selected examples of medication-induced injury of the intestinal tract in which the pathology can be recognized, particularly on biopsies, with a focus on newly described medication-induced gastrointestinal effects.

Esophagitis: Old Histologic Concepts and New Thoughts

Context

Inflammatory lesions of the esophagus are a diverse group, often with nonspecific histologic findings. These benign changes can produce diagnostic difficulties for pathologists.

Objective

To discuss the typical histologic findings of a variety of the most common causes of esophagitis (reflux, eosinophilic esophagitis, infections, medications) along with less common issues such as sloughing esophagitis and skin disorders involving the squamous mucosa.

Data Sources

The literature has been reviewed to discuss histologic definitions of current and developing issues in the area of esophagitis.

Conclusions

Histologic features are not entirely sensitive and specific for inflammatory esophageal disorders. Awareness of these problems is essential; clinical and endoscopic information can be very useful in distinguishing among the various lesions.

Drug-induced injury in the gastrointestinal tract

Abnormalities of the gastrointestinal tract due to drug-induced injuries are common and often have important clinical consequences. Medications may cause damage by direct corrosive effects on mucosae or by alter processes, mucosal immunity, and local environmental conditions. The aim of this review is to guide practicing pathologists in the identification of drug-related injuries in gastrointestinal mucosal biopsies and resection specimens. Common causes of injury and their gross, endoscopic, and microscopic features are presented.