Supplementary Material for: Iron Mettle- Unveiling an Unusual Incidental Case Report of Esophageal Ulcer

Background: Erosive injury to the upper gastrointestinal tract caused by therapeutic oral iron supplements is a rare occurrence. Although erosive injury to the mucosa of the upper gastrointestinal (GI) tract is commonly associated with overdoses of oral iron supplements, similar injuries can also occur with doses within the normal therapeutic range. Reports have documented upper gastrointestinal disorders induced by iron, primarily affecting the stomach and occasionally the esophagus. Iron preparations are initially absorbed as ferrous iron and then oxidized to ferric iron. Excess ferric iron, surpassing the binding capacity of transferrin, a binding protein, leads to cellular damage. Ferric iron directly corrodes the gastrointestinal mucosa and disrupts various cellular processes by generating free radicals and initiating lipid peroxidation.Case Description:A 55-year-old female with dysphagia, pain and anorexia showed linear to circumferential ulcers covered extensively with white slough around the central esophagus with thickened and erythematous mucosa with focal erosions on esophagogastroduodenoscopy. Conclusions:This case highlights a rare case report of Iron- Induced esophageal ulcer found incidentally and the significance of acknowledging that iron preparations can harm the esophageal mucosa especially in an Indian population where anemia is fairly predominant.

背景：治疗性口服铁剂引发的上消化道（upper gastrointestinal tract）侵蚀性损伤较为罕见。尽管上消化道黏膜（mucosa）侵蚀性损伤常与口服铁剂过量相关，但即便使用正常治疗剂量范围（therapeutic range）内的铁剂，也可能出现类似损伤。已有文献报道铁制剂（iron preparations）诱导的上消化道疾病，病变主要累及胃部，偶尔累及食管。铁制剂最初以亚铁（ferrous iron）形式被吸收，随后被氧化为三价铁（ferric iron）。当过量的三价铁超出结合蛋白（binding protein）转铁蛋白（transferrin）的结合能力时，会引发细胞损伤（cellular damage）。三价铁可直接腐蚀消化道黏膜，并通过产生自由基（free radicals）、启动脂质过氧化（lipid peroxidation）反应，干扰多种细胞生理过程。
病例描述：一名55岁女性患者，存在吞咽困难（dysphagia）、疼痛及厌食（anorexia）症状，食管胃十二指肠镜检查（esophagogastroduodenoscopy）显示食管中段可见线状至环形溃疡，表面广泛覆盖白色腐苔，黏膜增厚伴红斑（erythematous），可见局灶性糜烂（focal erosions）。
结论：本病例为一例偶然检出的铁剂诱导性食管溃疡（esophageal ulcer）罕见病例报告，旨在强调认识到铁制剂可损伤食管黏膜的临床意义，尤其在贫血（anemia）相当高发的印度人群中，该问题的临床关注度尤为重要。