对2021年1月—2025年10月于北京大学第三医院儿科确诊的4例胶原性胃炎（collagenous gastritis, CG）患儿的临床资料进行回顾性分析。患儿起病中位年龄为10.8岁，均有缺铁性贫血，其中2例伴有腹痛。胃镜下均表现为结节样外观，病理结果均证实上皮下胶原带厚度>10 μm，并观察到不同的炎症细胞浸润模式（2例为嗜酸细胞增多型，1例为淋巴细胞性胃炎型），其中2例患儿合并胶原性十二指肠炎，均未合并胶原性结肠炎。血清学检查显示，1例血清抗核抗体低滴度阳性，1例胃泌素17水平升高。所有患儿均接受铁剂治疗，其中3例联合胃黏膜保护剂，1例应用糖皮质激素。在获得随访的3例患儿中，临床症状及血红蛋白均有改善，其中2例胃黏膜炎症及胶原沉积出现组织学减轻。提示儿童CG以缺铁性贫血和胃结节样改变为主要表现，部分患儿合并十二指肠受累，强调了对确诊患儿进行全消化道评估的必要性；CG的诊断依赖于特征性病理及内镜表现，但仍需关注潜在的生物标志物，综合治疗（补铁、黏膜保护剂及必要时使用糖皮质激素）可取得良好的临床与组织学缓解。

The clinical data of 4 pediatric patients with collagenous gastritis (CG) diagnosed at the Department of Pediatrics of Peking University Third Hospital between January 2021 and October 2025 were retrospectively analyzed. The median age at onset was 10.8 years. All patients presented with iron-deficiency anemia, and two also experienced abdominal pain. Gastroscopy in all cases revealed a nodular gastric mucosal appearance. Histopathological examination confirmed subepithelial collagen band thickness greater than 10 μm in all patients, with varied patterns of inflammatory infiltrate, including two cases with eosinophil-predominant inflammation and one with lymphocytic gastritis. Two patients were found to have collagenous duodenitis, while none showed collagenous colitis. Serological testing identified one patient with low-titer positive antinuclear antibodies and another with elevated gastrin-17 levels. Treatment consisted of iron supplementation in all cases, combined with gastric mucosal protectants in three patients and glucocorticoid therapy in one patient. Follow-up of three patients showed clinical improvement with resolution of anemia, and two also demonstrated histological improvement with reduced gastric inflammation and collagen deposition. Pediatric CG is characterized primarily by iron-deficiency anemia and nodular gastric mucosal changes, accompanied by duodenal involvement in some patients. These findings underline the importance of a comprehensive evaluation of the entire gastrointestinal tract. Diagnosis relies on distinct endoscopic and pathological features, while attention should also be paid to potential biomarkers. A combined treatment approach, including iron supplementation, mucosal protection, and glucocorticoids when necessary, may lead to clinical and histological remission.