Lymphocytic Gastritis: Clinicopathologic Features, Etiologic Associations, and Pathogenesis

Prevalence and Clinical Significance of Helicobacter Pylori-negative Chronic Gastritis in Children

OBJECTIVES

The clinical significance of Helicobacter pylori-negative chronic gastritis (HPNCG) in children is unclear. We examined this issue in patients who had undergone esophagogastroduodenoscopy with systematic gastric sampling.

METHODS

Data of 1178 consecutive children who underwent diagnostic esophagogastroduodenoscopy were collected. Baseline characteristics and long-term outcomes were compared between children with active and inactive HPNCG and those with normal gastric histology. Follow-up data were available for up to 13 years.

RESULTS

Altogether 24 (2.0%) children had active and 235 (19.9%) inactive HPNCG, 27 (2.3%) were Hpylori-positive, 46 (3.9%) had other gastric pathology, and 846 (71.8%) normal histology. Diarrhea (31.3% vs 25.1%, P  = 0.033), poor growth (23.6% vs 14.7%, P  < 0.001), bloody stools (13.9% vs 7.2%, P < 0.001), anemia (46.5% vs 23.4%, P < 0.001), hypersedimentation (39.7% vs 21.4%, P < 0.001), hypoalbuminemia (40.4% vs 16.2%, P < 0.001), and elevated fecal calprotectin (62.4% vs 31.5%, P < 0.001) were more common and heartburn (13.9% vs 22.9%, P = 0.002) less common in the HPNCG group than in the controls. Both active (OR 3.64,95% CI 1.35-9.82) andinactive (2.98, 2.18-4.08) HPNCG predicted a diagnosis in the initial investigations. Crohn disease (41.7%) was the most common diagnosis in active HPNCG and celiac disease (37.4%) in inactive HPNCG. During follow-up, 7 (9.9%) of the 71 initially nondiagnosed HPNCG children received a diagnosis.

CONCLUSIONS

HPNCG is a frequent finding in children undergoing EGD, the active form being associated especially with Crohn disease and the inactive with celiac disease. The long-term prognosis of patients with HPNCG who do not receive an initial diagnosis is good.

Lymphocytic gastritis in a patient with dyspepsia

Lymphocytic gastritis (LG) is uncommon and presents histologically with a nonspecific inflammatory pattern. It is most often associated with celiac disease and Helicobacter pylori gastritis and is rarely associated with other conditions including lymphoma. LG is of clinical importance since its recognition should prompt further clinical evaluation for other disorders.

Propionibacterium acnes overabundance and natural killer group 2 member D system activation in corpus-dominant lymphocytic gastritis

Corpus‐dominant lymphocytic gastritis (LyG) is characterized by CD8⁺ T‐cell infiltration of the stomach epithelium by a so far uncharacterized mechanism. Although Helicobacter pylori is typically undetectable in LyG, patients respond to H. pylori antibiotic eradication therapy, suggesting a non‐H. pylori microbial trigger for the disease. Comparative microbiota analysis of specimens from LyG, H. pylori gastritis and healthy controls precluded involvement of H. pylori in LyG but identified Propionibacterium acnes as a possible disease trigger. In addition, the natural killer group 2 member D (NKG2D) system and the proinflammatory cytokine interleukin (IL)‐15 are significantly upregulated in the gastric mucosa of LyG patients, and gastric epithelial cells respond to microbe‐derived stimuli, including live P. acnes and the microbial products short‐chain fatty acids, with induction of NKG2D ligands. In contrast, H. pylori infection does not activate or even repress NKG2D ligands. Together, our findings identify P. acnes as a possible causative agent for LyG, which is dependent on the NKG2D system and IL‐15 activation. © 2016 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland.

Iron deficiency anemia due to lymphocytic gastritis with Helicobacter pylori infection in childhood: case report

Lymphocytic gastritis (LG) is a chronic inflammatory process of poorly understood pathogenesis. We report the case of a 12-year-old premenstrual girl with refractory iron deficiency anemia in which the oral iron absorption challenge suggested iron malabsorption. Laboratory studies ruled out celiac disease and autoimmune gastritis, and carbon-13 urea breath test for Helicobacter pylori was also negative. Upper endoscopy with gastric body and antral mucosa biopsies revealed a LG with focal intestinal metaplasia and H. pylori infection. H. pylori eradication was undertaken with success and 3 months later her hematologic parameters normalized. Histologic reevaluation showed disappearance of LG. This case shows that investigation of malabsorption disease in the presence of refractory iron deficiency anemia can lead to the diagnosis of important gastric diseases, even in the absence of gastrointestinal symptoms. This nonceliac child was diagnosed with a severe histopathologic pattern of LG, with potential risk of malignant transformation, which was completely reverted with adequate H. pylori eradication treatment.