Supplementary Material for: A Rapid Development of Post-Colonoscopy Appendicitis Within Twelve Hours: A Case Report

Introduction
Colon cancer has seen a steady decline in incidence due to increased colonoscopy use. We can assume that this increased use, results in a higher incidence of post-colonoscopy complications such postpolypectomy syndrome, perforation and post-colonoscopy appendicitis (PCA). In this report we present a case of post-colonoscopy appendicitis presenting to the emergency department within 12 hours of a screening colonoscopy.
Case Presentation
Our patient, a 77-year-old male, underwent an uncomplicated screening colonoscopy and was discharged home after briefly being monitored without any complaints. Later that day, the patient presented to the emergency department complaining of acute generalized abdominal pain. On presentation, the patient was found to be hypertensive and febrile with a distended abdomen with right lower quadrant tenderness on examination. Laboratory investigations noted an elevated white blood cell count with no evidence of acute appendicitis or focal inflammatory changes on contrast-enhanced abdominal and pelvic computer tomography. The patient was subsequently admitted and, developed worsening right lower quadrant abdominal pain and distention overnight. Due to this worsening clinical condition, the decision was made to proceed with a diagnostic laparoscopy. After frank pus was found laparoscopically around the cecum and appendix, it was then converted to an exploratory laparotomy. Subsequently, a perforated gangrenous appendix was found with an erythematous and indurated cecum.
Conclusion
Major complications of colonoscopy can include perforation and/or post-colonoscopy bleeding which have been shown to have a respective incidence of 0.21% and 0.1%. With the anticipated rise in the number of colonoscopies, much rarer complication such as PCA with an incidence of less than 0.05% will be seen more frequently. Due to its nonspecific presentation, it is necessary for providers to consider PCA as an important differential for all patients presenting with abdominal pain after a colonoscopy.

引言
由于结肠镜检查（colonoscopy）的应用增加，结肠癌的发病率呈稳步下降趋势。我们可以推测，结肠镜检查使用率的提升会导致结肠镜检查后并发症的发生率升高，例如息肉切除术后综合征（postpolypectomy syndrome）、穿孔以及结肠镜检查后阑尾炎（post-colonoscopy appendicitis, PCA）。本报告展示一例在筛查性结肠镜检查后12小时内于急诊科就诊的结肠镜检查后阑尾炎病例。

病例报告
患者为77岁男性，接受了无并发症的筛查性结肠镜检查，短暂监测后无任何不适主诉，遂出院回家。当日晚些时候，患者因急性全腹痛前往急诊科就诊。就诊时，患者表现为高血压、发热，查体可见腹胀，右下腹压痛。实验室检查显示白细胞计数升高，但增强腹盆腔计算机断层扫描（computer tomography）未提示急性阑尾炎或局灶性炎症改变。患者随后入院，夜间出现右下腹腹痛及腹胀加重。鉴于临床状况恶化，决定实施诊断性腹腔镜手术（diagnostic laparoscopy）。术中于盲肠及阑尾周围发现明显脓性渗出物，遂转为开腹探查术。术中可见穿孔坏疽性阑尾，盲肠发红且质地发硬。

结论
结肠镜检查的主要并发症包括穿孔和/或结肠镜检查后出血，其发生率分别为0.21%和0.1%。随着结肠镜检查数量的预期增长，诸如结肠镜检查后阑尾炎这类发生率低于0.05%的罕见并发症将会更为多见。由于其临床表现缺乏特异性，临床医师需将结肠镜检查后阑尾炎作为所有结肠镜检查后出现腹痛患者的重要鉴别诊断之一。