艰难梭菌感染已成为美国医院内与医疗保健相关感染的最常见原因,估计一年内美国患者中有 500,000 例感染,29,000 例死亡(初次诊断后 30 天内)。大约 65% 的病例与医疗保健有关(包括养老院和在门诊就诊过的患者),但只有 24% 的病例在住院期间发病。医疗保健相关感染的发病率为 92.8/100,000,而社区相关感染的发病率为 48.2/100,000。白人、女性和 65 岁及以上患者的感染率较高。[4]Lessa FC, Mu Y, Bamberg WM, et al. Burden of Clostridium difficile infection in the United States. N Engl J Med. 2015 Feb 26;372(9):825-34.http://www.nejm.org/doi/pdf/10.1056/NEJMoa1408913http://www.ncbi.nlm.nih.gov/pubmed/25714160?tool=bestpractice.com 一项前瞻性研究发现,艰难梭菌感染约占急诊科出现腹泻但无呕吐患者的 10%,其中超过三分之一的患者没有传统的感染危险因素。[5]Abrahamian FM, Talan DA, Krishnadasan A, et al; EMERGEncy ID NET Study Group. Clostridium difficile infection among US emergency department patients with diarrhea and no vomiting. Ann Emerg Med. 2017 Jul;70(1):19-27;e4.http://www.ncbi.nlm.nih.gov/pubmed/28242058?tool=bestpractice.com
由于毒性更强的北美脉冲场凝胶电泳 1 型 (NAP1) 菌株(也称为 PCR 核糖型 027 流行株)的出现,流行病学在 21 世纪发生了变化。[6]Bartlett JG, Perl TM. The new Clostridium difficile - what does it mean? N Engl J Med. 2005 Dec 8;353(23):2503-5.http://www.ncbi.nlm.nih.gov/pubmed/16322604?tool=bestpractice.com[7]Loo VG, Poirier L, Miller MA, et al. A predominantly clonal multi-institutional outbreak of Clostridium difficile-associated diarrhea with high morbidity and mortality. N Engl J Med. 2005 Dec 8;353(23):2442-9.http://www.nejm.org/doi/full/10.1056/NEJMoa051639#t=articlehttp://www.ncbi.nlm.nih.gov/pubmed/16322602?tool=bestpractice.com[8]McDonald LC, Killgore GE, Thompson A, et al. An epidemic, toxin gene-variant strain of Clostridium difficile. N Engl J Med. 2005 Dec 8;353(23):2433-41.http://www.nejm.org/doi/full/10.1056/NEJMoa051590#t=articlehttp://www.ncbi.nlm.nih.gov/pubmed/16322603?tool=bestpractice.com 北美、英国、欧洲和亚洲暴发了疫情。自从首次被分离后,NAP1 菌株的流行率一直在下降,但在美国仍是一个重大问题。这种菌株的出现可能是广泛使用氟喹诺酮类药物的结果。[9]Bartlett JG. Narrative review: the new epidemic of Clostridium difficile-associated enteric disease. Ann Intern Med. 2006 Nov 21;145(10):758-64.http://www.ncbi.nlm.nih.gov/pubmed/17116920?tool=bestpractice.com NAP1 菌株在医疗卫生相关感染中更普遍。[4]Lessa FC, Mu Y, Bamberg WM, et al. Burden of Clostridium difficile infection in the United States. N Engl J Med. 2015 Feb 26;372(9):825-34.http://www.nejm.org/doi/pdf/10.1056/NEJMoa1408913http://www.ncbi.nlm.nih.gov/pubmed/25714160?tool=bestpractice.com
据报道,复发率为 5% 到 50% 不等,但有一项研究发现,21% 的医疗保健相关感染和 14% 的社区相关感染中至少有一次复发。[4]Lessa FC, Mu Y, Bamberg WM, et al. Burden of Clostridium difficile infection in the United States. N Engl J Med. 2015 Feb 26;372(9):825-34.http://www.nejm.org/doi/pdf/10.1056/NEJMoa1408913http://www.ncbi.nlm.nih.gov/pubmed/25714160?tool=bestpractice.com 初次发作后第一次复发的风险为 25%,第二次复发风险为 38%,第三次复发风险为 29%,第四次复发风险为 27%。严重感染的风险随着每次后续疾病的复发而降低。[10]Sheitoyan-Pesant C, Abou Chakra CN, Pépin J, et al. Clinical and healthcare burden of multiple recurrences of Clostridium difficile infection. Clin Infect Dis. 2016 Mar 1;62(5):574-80.https://academic.oup.com/cid/article/62/5/574/2462831http://www.ncbi.nlm.nih.gov/pubmed/26582748?tool=bestpractice.com 近年来,多次复发感染的年发病率有所增加。复发性感染的危险因素包括女性性别、年龄增长、慢性肾脏病、在养老院被诊断以及近期使用皮质类固醇或质子泵抑制剂。[11]Ma GK, Brensinger CM, Wu Q, et al. Increasing incidence of multiply recurrent Clostridium difficile infection in the United States: a cohort study. Ann Intern Med. 2017 Aug 1;167(3):152-8.http://www.ncbi.nlm.nih.gov/pubmed/28672282?tool=bestpractice.com
在欧洲急诊医院内,艰难梭菌导致了 48% 的医疗卫生相关胃肠道感染。[12]European Centre for Disease Prevention and Control (ECDC). Point prevalence survey of healthcare-associated infections and antimicrobial use in European acute care hospitals. 2011-2012. July 2013 [internet publication].https://ecdc.europa.eu/sites/portal/files/media/en/publications/Publications/healthcare-associated-infections-antimicrobial-use-PPS.pdf 在英国,2017 年 1 月至 2018 年 1 月期间就上报了 5038 例 2 岁及以上的患者(仅综合医院分配的病例)。[13]Public Health England. Clostridium difficile infection: monthly data by NHS acute trust. March 2018 [internet publication].https://www.gov.uk/government/statistics/clostridium-difficile-infection-monthly-data-by-nhs-acute-trust据报道,亚洲的发病率与欧洲和北美的发病率近似。[14]Borren NZ, Ghadermarzi S, Hutfless S, et al. The emergence of Clostridium difficile infection in Asia: a systematic review and meta-analysis of incidence and impact. PLoS One. 2017 May 2;12(5):e0176797.https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5413003/http://www.ncbi.nlm.nih.gov/pubmed/28463987?tool=bestpractice.com