Ellström P, Feodoroff B, Hänninen M-L, Rautelin H
Department of Medical Sciences, Clinical Bacteriology, Uppsala University, Uppsala, Sweden.
Clin Microbiol Infect. 2014 Jun;20(6):524-9. doi: 10.1111/1469-0691.12382. Epub 2013 Oct 29.
Campylobacter jejuni is a highly diverse enteropathogen that is commonly detected worldwide. It can sometimes cause bacteraemia, but the bacterial characteristics facilitating bloodstream infection are not known. A total of 73 C. jejuni isolates, consecutively collected from blood-borne infections during a 10-year period all over Finland and for which detailed clinical information of the patients were available, were included. We screened the isolates by PCR for the lipooligosaccharide (LOS) locus class and for the presence of the putative virulence genes ceuE, ciaB, fucP, and virB11. The isolates were also tested for γ-glutamyl transpeptidase production. The results were analysed with respect to the clinical characteristics of the patients, and the multilocus sequence types (MLSTs) and serum resistance of the isolates. LOS locus classes A, B, and C, which carry genes for sialylation of LOS, were detected in only 23% of the isolates. These isolates were not more resistant to human serum than those with the genes of non-sialylated LOS locus classes, but were significantly more prevalent among patients with underlying diseases (p 0.02). The fucose permease gene fucP was quite uncommon, but was associated with the isolates with the potential to sialylate LOS (p <0.0001). LOS locus classes and some of the putative virulence factors were associated with MLST clonal complexes. Although some of the bacterial characteristics studied here have been suggested to be important for the invasiveness of C. jejuni, they did not explain why the clinical isolates in the present study were able to cause bacteraemia.
空肠弯曲菌是一种高度多样化的肠道病原体，在全球范围内普遍被检测到。它有时会引起菌血症，但促进血流感染的细菌特征尚不清楚。研究纳入了在芬兰全国10年期间从血行感染中连续收集的73株空肠弯曲菌分离株，且可获得患者的详细临床信息。我们通过聚合酶链反应（PCR）筛选分离株的脂寡糖（LOS）基因座类别以及假定的毒力基因ceuE、ciaB、fucP和virB11的存在情况。还对分离株进行了γ-谷氨酰转肽酶产生的检测。根据患者的临床特征、分离株的多位点序列类型（MLSTs）和血清抗性对结果进行了分析。携带LOS唾液酸化基因的LOS基因座类别A、B和C仅在23%的分离株中被检测到。这些分离株对人血清的抗性并不比那些具有非唾液酸化LOS基因座类别的基因的分离株更强，但在患有基础疾病的患者中显著更为普遍（p<0.02）。岩藻糖通透酶基因fucP相当罕见，但与具有唾液酸化LOS潜力的分离株相关（p<0.0001）。LOS基因座类别和一些假定的毒力因子与MLST克隆复合体相关。尽管本文研究的一些细菌特征已被认为对空肠弯曲菌的侵袭性很重要，但它们并不能解释本研究中的临床分离株为何能够引起菌血症。
