胶囊内镜对不明原因消化道出血诊断价值的评估

背景：对于不明原因消化道出血（OGIB），胶囊内镜是一种有价值的诊断方法。但迄今为止，该技术在OGIB诊断中应用的研究多限于小样本病例。目的：评价胶囊内镜对OGIB的诊断价值，确定其敏感性，特异性，阳性，阴性预测值和总诊断率。方法：2002年5月-2005年1月，对连续选取的91例OGIB患者行胶囊内镜检查94次，对胶囊排出时间，再检查，治疗，再出血，依从性和并发症等情况进行随访观察。结果：胶囊内镜检查的阳性率为74.7%，疑诊率为11.0%，阴性率为14.3%。其诊断OGIB的敏感性，特异性以及阳性，阴性预测值分别为94.6%、88.9%和80.0%，总诊断率为93.8%。检查过程中仅1例（1.1%）患者发生胶囊滞留，后经手术取出并证实为克罗恩病所致的肠腔狭窄。结论：胶囊内镜对于OGIB是一种有效而安全的检查手段，迟早行胶囊内镜检查可使患者早日明确诊断并得到及时治疗，从而改善预后。

Evaluation of Capsule Endoscopy in the Diagnosis of Obscure Gastrointestinal Bleeding

Background: Capsule endoscopy plays an important role in the diagnosis of obscure gastrointestinal bleeding (OGIB). However, this technique has been studied mainly in small number of OGIB cases since its introduction. Aims: To evaluate the diagnostic value of capsule endoscopy for OGIB patients, and to estimate its sensitivity, specificity, positive and negative predictive values, and overall diagnostic yield. Methods: 91 consecutive OGIB patients referred for capsule endoscopy (94 examinations) from May 2002 to Jan. 2005 were enrolled. After completing the examination, follow-up data including excretion of capsule endoscope in the stool, further examination, treatment, bleeding episodes, compliance and complications were recorded and analyzed. Results: The findings of capsule endoscopy were positive in 74.7% cases, suspicious in 11.0% cases, and negative in 14.3% cases, respectively. Sensitivity, specificity, positive and negative predictive values and overall diagnostic yield of capsule endoscopy were 94.6%, 88.9%, 96.4%, 80.0%, and 93.8%, respectively. Capsule retention because of unsuspected stenosis occurred in 1 patient (1.1%) and was removed by surgery. The final diagnosis was Crohn's disease. Conclusions: Capsule endoscopy is a safe and effective diagnostic tool for OGIB. If done early in the course of workup, capsule endoscopy can lead to definite diagnosis and better treatment in a substantial proportion of patients, and then improve their prognosis.