Department of Medicine, Kainuu Central Hospital, Kajaani, Finland.
Finnish Food Safety Authority Evira, Helsinki, Finland.
Ann Rheum Dis. 2014 Oct;73(10):1793-6. doi: 10.1136/annrheumdis-2013-203431. Epub 2013 Jul 12.
We describe the epidemiological and microbiological process in the clearing of a foodborne outbreak of Yersinia pseudotuberculosis O:1 linked to raw carrots and frequency of the associated reactive extra-gastrointestinal manifestations.
The patient samples were investigated by routine culture or antibody testing methods. The real-time bacterial PCR was used to detect Y pseudotuberculosis in samples from the grated carrots and in those taken from the carrot storage. Genotype of bacterial isolates was determined by pulsed-field gel electrophoresis. For case identification, we retrospectively looked over the laboratory files of the central hospital focusing on the time period of the outbreak.
Altogether 49 case patients were identified. Y pseudotuberculosis was detected by real-time PCR analysis in samples taken from grated carrots and from the carrot distributor. Bacterial isolates originating from the farm environment showed identical serotype (O:1) and genotype (S12) with the patients' isolates. Among 37 adults, reactive arthritis (ReA) was found in 8 (22%) and three adults had probable ReA. Six (67%) out of nine human leucocyte antigen (HLA) typed patients with ReA were HLA-B27 positive. Erythema nodosum was found in 42% of the 12 children, whereas none of them had definite ReA.
In this outbreak, Y pseudotuberculosis was for the first time detected in both patient and food samples. ReA was more common than earlier reported in the outbreaks associated with this pathogen; the reason may be that the previous outbreaks have occurred among children. HLA-B27 frequency was higher than usually reported in single-source outbreaks of ReA.
我们描述了与生胡萝卜有关的食源性耶尔森菌假结核 O:1 暴发的流行病学和微生物学过程，以及相关的反应性肠外表现的频率。
通过常规培养或抗体检测方法对患者样本进行检测。采用实时细菌 PCR 检测生胡萝卜和胡萝卜储存样本中的假结核耶尔森菌。通过脉冲场凝胶电泳确定细菌分离株的基因型。为了进行病例鉴定，我们回顾了中心医院的实验室档案，重点关注暴发期间。
共发现 49 例病例患者。实时 PCR 分析在取自磨碎胡萝卜和胡萝卜分销商的样本中检测到假结核耶尔森菌。来自农场环境的细菌分离株与患者分离株具有相同的血清型（O:1）和基因型（S12）。在 37 名成年人中，发现反应性关节炎（ReA）8 例（22%），3 例成人可能患有 ReA。6 例（67%）接受 HLA 分型的 ReA 患者中有 6 例 HLA-B27 阳性。12 例儿童中有 42%出现结节性红斑，而他们均无明确的 ReA。
在此次暴发中，首次在患者和食物样本中检测到假结核耶尔森菌。ReA 的发病率高于以往报道的与该病原体相关的暴发；原因可能是以往的暴发发生在儿童中。HLA-B27 的频率高于以往报道的单源暴发。
