15-year-old girl with metaplastic atrophic gastritis and enterochromaffin-like cell hyperplasia

Clinical Heterogeneity of Early-Onset Autoimmune Gastritis: From the Evidence to a Pediatric Tailored Algorithm

Autoimmune gastritis (AIG) is an uncommon and often underestimated condition in children, characterized by chronic stomach inflammation leading to the destruction of oxyntic glands with subsequent atrophic and metaplastic changes. This condition is associated with hypo-/achlorhydria, impairing iron and vitamin B12 absorption. The pathogenesis involves the activation of helper type 1 CD4+/CD25-T-cells against parietal cells. Clinical manifestations in children are not specific and include abdominal pain, bloating, nausea, vomiting, and iron deficiency anemia (IDA). The disease is also linked to an increased risk of pernicious anemia, intestinal-type gastric cancer, and type I neuroendocrine tumors. AIG is often diagnosed through the presence of autoantibodies in the serum, such as parietal cell (APCA) and intrinsic factor (IF) antibodies. However, therapeutic recommendations for pediatric AIG are currently lacking. We aim to present two clinical cases of pediatric-onset AIG, highlighting the heterogeneous clinical manifestations and the challenges in diagnosis with the support of an updated literature review. A 9-year-old girl presented with refractory IDA, initial hypogammaglobulinemia, and a 12-year-old boy was initially diagnosed with eosinophilic esophagitis. Both cases underline the importance of considering AIG in children with chronic gastrointestinal symptoms and gastric atrophy. Diagnostic workup, including endoscopy and serological tests, is crucial for accurate identification. A better understanding of this condition is imperative for timely intervention and regular monitoring, given the potential long-term complications, including the risk of malignancy. These cases contribute to expanding the clinical spectrum of pediatric AIG and highlight the necessity for comprehensive evaluation and management in affected children.

Autoimmune Gastritis in the Pediatric Age: An Underestimated Condition Report of Two Cases and Review

Background: Diagnosis of pediatric autoimmune gastritis (AIG) in children is important due to poor outcome and risk of malignancy. This condition is often underestimated in the clinico-pathologic diagnostic work-up, leading to delayed time-to-diagnosis. To increase the awareness of this condition in the pediatric population, we present two cases encountered at our institution, discuss their clinical, biological, and histological presentations in relation with evidence from the literature, and propose an algorithm for diagnosis and follow-up of AIG in children. Case presentation: Two patients (12 and 17 years old) presented with iron deficiency anemia and negative family history for autoimmune disorders. In both cases, the final diagnosis of autoimmune gastritis was delayed until pathological examination of endoscopic gastric biopsies showed atrophy of oxyntic glands. Helicobacter pylori search was negative. Follow up biopsies revealed persistent disease. Literature review on this condition shows unclear etiology and poor long term outcome in some patients because of increased risk of malignancy. Conclusions: AIG should be considered in the differential diagnosis of iron deficiency anemia in the pediatric population.Standardized clinico-pathologic work-up is mandatory. Endoscopic follow-up should be performed due to the risk of malignancy.

Pediatric non-Helicobacter pylori atrophic gastritis: a case series

Although autoimmune atrophic gastritis is classically a disease of elderly adults, recent studies have described the disease in younger adults, particularly in those with other autoimmune diseases and iron-deficiency anemia. Atrophic gastritis in pediatrics is a rare and possibly underdiagnosed entity that has been primarily reported as single-case reports. This retrospective study of atrophic gastritis not associated with Helicobacter pylori infection was performed to further expand the knowledge of clinical presentation, pathologic findings, and natural history of this disease in the pediatric population. Twelve patients with a histologic diagnosis of atrophic gastritis were identified, with an age range of 8 months to 18 years. Seven had other autoimmune diseases and/or immunodeficiency. Atrophy was confined to the oxyntic mucosa in 10 patients, with intramucosal inflammation in a diffuse or basal-predominant pattern. Active inflammation was present in 7 patients. Pseudopyloric, intestinal, or squamous/mucinous metaplasia was seen at initial biopsy or on follow-up in 8 patients, and enterochromaffin-like cell hyperplasia was seen in 5. One patient developed an adenocarcinoma during the follow-up period of 10 years. Two false-negative diagnoses were retrospectively identified. In the majority of cases, the possibility of atrophic gastritis was not raised by the submitting physician, and the endoscopic findings were not specific. Therefore, accurate diagnosis requires a high degree of suspicion on the part of the pathologist, and the diagnosis should be considered particularly in patients with a clinical history of other autoimmune diseases or iron-deficiency anemia.

Autoimmune gastritis presenting as iron deficiency anemia in childhood

AIM: To characterize clinical, laboratorial, and histological profile of pediatric autoimmune gastritis in the setting of unexplained iron deficiency anemia investigation.

METHODS: A descriptive, observational study including pediatric patients with a diagnosis of autoimmune gastritis (positive parietal cell antibody and gastric corpus atrophy) established in a 6 year period (2006-2011) in the setting of refractory iron deficiency anemia (refractoriness to oral iron therapy for at least 6 mo and requirement for intravenous iron therapy) investigation, after exclusion of other potentially contributing causes of anemia. Helicobacter pylori (H. pylori) infection and anti-secretory therapy were also excluded. Data were retrospectively collected from clinical files, including: demographic data (age, gender, and ethnic background), past medical history, gastrointestinal symptoms, familial history, laboratorial evaluation (Hb, serum ferritin, serum gastrin, pepsinogen I/ pepsinogen II, B12 vitamin, intrinsic factor autoantibodies, thyroid autoantibodies, and anti-transglutaminase antibodies), and endoscopic and histological findings (HE, Periodic Acid-Schiff/Alcian blue, gastrin, chromogranin A and immunochemistry analysis for CD3, CD20 and CD68). Descriptive statistical analysis was performed (mean, median, and standard deviation).

RESULTS: We report a case-series concerning 3 girls and 2 boys with a mean age of 13.6 ± 2.8 years (3 Caucasian and 2 African). One girl had type I diabetes. Familial history was positive in 4/5 cases, respectively for autoimmune thyroiditis (2/5), sarcoidosis (1/5) and multiple myeloma (1/5). Laboratorial evaluation on admission included: Hb: 9.5 ± 0.7 g/dL; serum ferritin: 4.0 ± 0.9 ng/mL; serum gastrin: 393 ± 286 pg/mL; low pepsinogen I/ pepsinogen II ratio in 1/5 patients; normal vitamin B12 levels (analyzed in 3 patients). Endoscopy findings included: duodenal nodularity (2/5) and gastric fold softening (2/5), and histological evaluation showed corpus atrophic gastritis with lymphocytic infiltration (5/5), patchy oxyntic gland mononuclear cell infiltration (5/5), intestinal and/or pseudo-pyloric metaplasia in corpus mucosa (4/5), and enterochromaffin cell hyperplasia (4/5). Immunochemistry for gastrin on corpus biopsies was negative in all cases. Duodenal histology was normal. All biopsies were negative for H. pylori (Giemsa staining and cultural examination).

CONCLUSION: We highlight autoimmune gastritis as a diagnosis to be considered when investigating refractory iron deficiency anemia in children, particularly in the setting of a personal/familial history of autoimmune disease, as well as the diagnostic contribution of a careful immunohistological evaluation.