Supplementary Material for: Helicobacter pylori Reinfection Diagnosed by Endoscopic and Histologic Recurrence in a Patient with Gastric Mucosa-Associated Lymphoid Tissue Lymphoma

Helicobacter pylori infection is a major cause of gastric mucosa-associated lymphoid tissue (MALT) lymphoma. Successful H. pylori eradication can induce a complete remission (CR); however, it takes a long time. In this case, the recurrence of gastric MALT lymphoma was observed by endoscopic and histologic findings during a 11-year follow-up and due to H. pylori reinfection twice. After the first successful eradication and achieving histologic CR, the patient was starting to work at a nursing home for older adults, where she frequently came in contact with their vomitus or feces. In the examinations 2 years later after the first successful eradication, endoscopic and histologic findings have demonstrated deterioration. Similar findings were continuously observed in the examinations 3 months later, and H. pylori reinfection was confirmed by the rapid urease test. After the second successful eradication, endoscopic and histologic CR of gastric MALT lymphoma was achieved. However, endoscopic and histologic findings have shown deterioration again 1 year later after the histologic CR and at 3.5 years later after the second successful eradication. H. pylori reinfection was confirmed by the repeated urea breath test, and the patient had received the third eradication treatment; and the patient had achieved successful eradication. In addition, proper hygiene practices were advised to avoid H. pylori reinfection. H. pylori reinfection is very rare in adults after successful eradication in developed countries. After successful eradication and proper hygiene practice, endoscopic and histologic CR has been maintained for 2 years up to the present.幽门螺杆菌（Helicobacter pylori，Hp）感染是胃黏膜相关淋巴组织（mucosa-associated lymphoid tissue，MALT）淋巴瘤的主要致病因素。成功根除Hp可诱导完全缓解（complete remission，CR），但该过程耗时较长。本病例中，患者在11年随访期间经内镜及组织学检查发现胃MALT淋巴瘤复发，且两次复发均与Hp再感染相关。首次成功根除Hp并达到组织学完全缓解后，患者就职于一家老年护理院，期间频繁接触老年患者的呕吐物与粪便。首次根除成功后2年的复查中，内镜及组织学检查显示病情恶化；3个月后的后续检查亦见类似表现，且快速尿素酶试验（rapid urease test）证实Hp再感染。第二次成功根除Hp后，患者实现胃MALT淋巴瘤的内镜及组织学完全缓解。然而，在组织学完全缓解后1年、第二次成功根除术后3.5年，内镜及组织学检查再次提示病情恶化，重复尿素呼气试验（urea breath test）证实Hp再感染，患者遂接受第三次根除治疗并成功根除Hp。此外，医师建议患者采取规范卫生习惯以预防Hp再感染。在发达国家，成人成功根除Hp后发生再感染的情况极为罕见。目前，患者坚持规范卫生习惯，其内镜及组织学完全缓解状态已维持2年至今。