中毒性巨结肠是各种病因所致结肠炎的严重并发症,可累及所有年龄段的男性和女性。中毒性巨结肠的总发病率难以确定,因为这取决于结肠炎和结肠扩张的病因。根据报告,在炎症性肠病 (inflammatory bowel disease, IBD) 患者中,中毒性巨结肠的终身发病率是 1% 至 5%,在伪膜性或艰难梭菌结肠炎患者中,终身发病率为 0.4% 至 3%。[2]Grieco MB, Bordan DL, Geiss AC, et al. Toxic megacolon complicating Crohn's colitis. Ann Surg. 1980 Jan;191(1):75-80.https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1344622/http://www.ncbi.nlm.nih.gov/pubmed/7352781?tool=bestpractice.com[3]Greenstein AJ, Sachar DB, Gibas A, et al. Outcome of toxic dilatation in ulcerative and Crohn's colitis. J Clin Gastroenterol. 1985 Apr;7(2):137-43.http://www.ncbi.nlm.nih.gov/pubmed/4008909?tool=bestpractice.com[4]Ausch C, Madoff RD, Gnant M, et al. Aetiology and surgical management of toxic megacolon. Colorectal Dis. 2006 Mar;8(3):195-201.http://www.ncbi.nlm.nih.gov/pubmed/16466559?tool=bestpractice.com 由于能够更早对严重加重情况的做出诊断并给予更好的药物治疗,IBD 相关性中毒性巨结肠的发病率逐渐降低,但是 IBD 患者在病程早期发生中毒性结肠炎/中毒性巨结肠的风险仍然最高,并且这可能是初始表现。在艰难梭菌相关性结肠炎患者中,中毒性巨结肠的发病率估计为 3%。[4]Ausch C, Madoff RD, Gnant M, et al. Aetiology and surgical management of toxic megacolon. Colorectal Dis. 2006 Mar;8(3):195-201.http://www.ncbi.nlm.nih.gov/pubmed/16466559?tool=bestpractice.com[5]Dallal RM, Harbrecht BG, Boujoukas AJ, et al. Fulminant Clostridium difficile: an underappreciated and increasing cause of death and complications. Ann Surg. 2002 Mar;235(3):363-72.https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1422442/http://www.ncbi.nlm.nih.gov/pubmed/11882758?tool=bestpractice.com 伪膜性结肠炎和其他感染性结肠炎的发病率的增加,很可能导致相关中毒性巨结肠的发病率增加。