Gastrointestinal bleeding caused by gastrointestinal tract involvement in patients with Klippel–Trenaunay syndrome (KTS) is extremely rare and often overlooked. Case presentation A 9-year-old girl who presented with chronic gastrointestinal bleeding was admitted to our hospital. Laboratory examinations revealed microcytic hypochromic anemia and a positive fecal occult blood test. Computed tomography (CT) of the lower limbs combined with physical examination confirmed KTS. The pelvic CT showed concentric thickening of the sigmoid colon and rectum, with progressive enhancement after the administration of a contrast agent. Colonoscopy demonstrated vascular malformations of the sigmoid colon and rectum. The patient was finally diagnosed with KTS with gastrointestinal tract involvement. The patient improved after receiving conservative treatment. A suspicion of gastrointestinal tract involvement as an etiology for gastrointestinal bleeding should not be overlooked in patients with KTS. Endoscopy and imaging modalities can synergistically help diagnose this condition.

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Klippel-Trenaunay 综合征胃肠道出血：1 例报告

Klippel-Trenaunay 综合征 (KTS) 患者由胃肠道受累引起的胃肠道出血极为罕见且经常被忽视。病例介绍 一名 9 岁女孩因慢性消化道出血入院。实验室检查显示小细胞性低色素性贫血和粪便潜血试验阳性。下肢计算机断层扫描 (CT) 结合体格检查证实了 KTS。盆腔 CT 显示乙状结肠和直肠同心增厚，注射造影剂后逐渐增强。结肠镜检查显示乙状结肠和直肠血管畸形。该患者最终被诊断为胃肠道受累的 KTS。患者接受保守治疗后好转。对于 KTS 患者，不应忽视胃肠道受累是胃肠道出血的病因。内窥镜检查和成像方式可以协同帮助诊断这种情况。