Bacterial Infections Unit, Department of Health Security, National Institute for Health and Welfare (THL), P.O. Box 30, 00271, Helsinki, Finland.
Infectious Disease Control Unit, Department of Health Security, National Institute for Health and Welfare (THL), P.O. Box 30, 00271, Helsinki, Finland.
Eur J Clin Microbiol Infect Dis. 2017 Oct;36(10):1939-1945. doi: 10.1007/s10096-017-3017-5. Epub 2017 May 30.
We evaluated Clostridium difficile (CD) diagnostics in Finnish clinical microbiology laboratories during 2006-2011, with an update in 2015, in relation to CD surveillance data of the National Infectious Disease Register (NIDR) and ribotyping data from the national reference laboratory during the years 2008-2015. In 2011, diagnostic activity varied regionally more than three-fold and the positivity rate ranged between 7 and 21%. Nucleic acid amplification testing (NAAT) was implemented in the regions with high activity and NAAT users tested 30% more patients and found 15% more cases per population than those not using it. Culture was performed in 79% of laboratories, primary toxin testing by enzyme immunoassay (EIA) in 83% and by NAAT in 17%. In 2014, 12/19 laboratories used NAAT as the primary detection method and four as the secondary method, and ten cultured. Increasing usage of NAAT was not systematically related to various trends detected regionally in annual CD rates. Polymerase chain reaction (PCR) ribotyping of 1771 CD isolates (4.1% of CD cases) identified 146 distinct profiles, of which 37% were binary toxin positive. The most common ribotype was 027, but its proportion decreased, while 078 slightly increased. Transition from culture to NAAT in CD infection (CDI) diagnostics did not cause a significant increase in the observed CDI incidence. Major differences between diagnostic activity, methods and strategies in different regions have persisted over the years, which should be considered when comparing the regional epidemiology of CDI.
我们评估了 2006-2011 年芬兰临床微生物学实验室中的艰难梭菌（CD）诊断情况，并在 2015 年进行了更新，同时还参考了国家传染病登记处（NIDR）的 CD 监测数据以及 2008-2015 年国家参考实验室的核糖体分型数据。2011 年，诊断活动在不同地区的差异超过三倍，阳性率在 7%至 21%之间。在活性较高的地区实施了核酸扩增检测（NAAT），使用 NAAT 的地区检测的患者比不使用 NAAT 的地区多 30%，每人口发现的病例比不使用 NAAT 的地区多 15%。79%的实验室进行培养，83%的实验室通过酶联免疫吸附试验（EIA）、17%的实验室通过 NAAT 进行初次毒素检测。2014 年，19 个实验室中的 12 个将 NAAT 作为主要检测方法，4 个作为次要检测方法，10 个进行培养。NAAT 使用量的增加与各地 CD 发病率的各种趋势没有系统关联。对 1771 株 CD 分离株（占 CD 病例的 4.1%）进行的聚合酶链反应（PCR）核糖体分型鉴定出 146 种不同的模式，其中 37%为双毒素阳性。最常见的核糖体型是 027，但比例下降，而 078 略有增加。在 CD 感染（CDI）诊断中，从培养到 NAAT 的转变并没有导致观察到的 CDI 发病率显著增加。多年来，不同地区在诊断活动、方法和策略方面存在显著差异，在比较 CDI 的地区流行病学时应予以考虑。
