Segal W N, Greenberg P D, Rockey D C, Cello J P, McQuaid K R
San Francisco Veterans Affairs Hospital, University of California San Francisco, USA.
Am J Gastroenterol. 1998 Feb;93(2):179-82. doi: 10.1111/j.1572-0241.1998.00179.x.
The objective of this study was to determine whether specific clinical symptoms associated with hematochezia are predictive of important GI pathology and whether full colonoscopic examination is necessary.
A total of 103 outpatients (> or = 45 yr) with hematochezia, defined as the passage of bright red blood per rectum, underwent anoscopy and colonoscopy. Before endoscopy, patients completed a detailed interview, quantitating the amount and frequency of bleeding, weight loss, use of aspirin/NSAIDs, change in bowel habits, family history, and prior GI illnesses. Based on this information, physicians were asked to predict whether the bleeding was from a perianal or more proximal site. At colonoscopy, pathology was stratified as either proximal or distal to the sigmoid/descending junction. Substantial pathology was defined as one or more adenomas > 8 mm, carcinoma, or colitis.
Anoscopy demonstrated internal and external hemorrhoids in 78 and 29 patients, respectively. On colonoscopy, 36 patients had 43 substantial lesions. Thirty-seven of these lesions were distal to the junction of the descending and sigmoid colons and six were proximal lesions. Four patients had cancer; all were distal lesions. Patients with substantial lesions were more likely to give a history of blood mixed within their stool (p = 0.03), to have more episodes of hematochezia per month (p = 0.008), and to have a significantly shorter duration of bleeding before medical evaluation (p = 0.02) than did patients without such lesions. However, the physician's clinical assessment did not predict reliably which patients were likely to have substantial pathology.
In patients with hematochezia, clinicians were unable to distinguish between those patients with and those without significant colonic lesions by history alone. Flexible sigmoidoscopy would have demonstrated most (95%) substantial lesions. The lesions that flexible sigmoidoscopy missed were an unlikely cause of bleeding in this small group of patients.
本研究的目的是确定与便血相关的特定临床症状是否可预测重要的胃肠道病变，以及是否有必要进行全结肠镜检查。
共有103例便血门诊患者（年龄≥45岁）接受了肛门镜检查和结肠镜检查，便血定义为经直肠排出鲜红色血液。在内镜检查前，患者完成了详细的访谈，对出血的量和频率、体重减轻、阿司匹林/非甾体抗炎药的使用、排便习惯改变、家族史和既往胃肠道疾病进行了量化。根据这些信息，要求医生预测出血是来自肛周还是更近端的部位。在结肠镜检查时，病理结果被分为乙状结肠/降结肠交界处近端或远端。重大病变定义为一个或多个直径>8mm的腺瘤、癌或结肠炎。
肛门镜检查分别在78例和29例患者中发现内痔和外痔。结肠镜检查显示，36例患者有43处重大病变。其中37处病变位于降结肠和乙状结肠交界处远端，6处为近端病变。4例患者患有癌症；均为远端病变。与无此类病变的患者相比，有重大病变的患者更有可能有大便中带血的病史（p = 0.03），每月便血次数更多（p = 0.008），且在接受医学评估前出血持续时间明显更短（p = 0.02）。然而，医生的临床评估并不能可靠地预测哪些患者可能有重大病变。
在便血患者中，临床医生仅通过病史无法区分有和没有显著结肠病变的患者。乙状结肠镜检查可发现大多数（95%）重大病变。在这一小群患者中，乙状结肠镜检查遗漏的病变不太可能是出血的原因。
