A gentleman in his early 40s with a background of schizophrenia on clozapine presented with a 2-month history of rectal bleeding, diarrhoea, weight loss, a microcytic anaemia and a quantitative faecal immunochemical test (qFIT) result >400 µg Hb/g. Colonoscopy demonstrated multiple large polypoid lesions in the rectum and in the sigmoid colon; the sigmoid was unable to be passed by the colonoscope due to narrowing of the lumen (figure 1). Prior to histology being reported, CT colonography was performed to further assess the colon. It reported four malignant-appearing lesions in the rectum and sigmoid with suspicious sigmoid and retroperitoneal lymph nodes (figure 2). Figure 1 Index colonoscopy demonstrating multiple erythematous polypoid lesions causing congestion and narrowing of the lumen throughout the sigmoid colon and rectum: (A) proximal sigmoid (white light endoscopy (WLE)), (B) distal sigmoid (WLE), (C) …

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精神分裂症患者直肠出血的异常原因

一位 40 岁出头的男士，患有精神分裂症，服用氯氮平，有 2 个月的直肠出血史、腹泻、体重减轻、小细胞性贫血，粪便定量免疫化学检测 (qFIT) 结果 > 400 µg Hb/g。结肠镜检查显示直肠和乙状结肠中有多个大的息肉样病变；由于管腔变窄，乙状结肠无法通过结肠镜（图 1）。在报告组织学之前，进行 CT 结肠成像以进一步评估结肠。它报告了直肠和乙状结肠中有四个恶性病变，并伴有可疑的乙状结肠和腹膜后淋巴结（图 2）。图 1 索引结肠镜检查显示多个红斑息肉样病变，导致整个乙状结肠和直肠内腔充血和狭窄：(A) 近端乙状结肠（白光内窥镜检查 (WLE)），(B) 远端乙状结肠 (WLE)，(C) …