Tropical Disease Research Center and Microbiology Faculty, Universidad de Costa Rica, 2060 San José, Costa Rica.
Research Center of Environmental Pollution (CICA), Universidad de Costa Rica, 2060 San José, Costa Rica.
J Food Prot. 2014 Jun;77(6):880-4. doi: 10.4315/0362-028X.JFP-13-368.
Arcobacter species have been recognized as potential food- and waterborne pathogens. The lack of standardized isolation methods and the relatively scarce knowledge about their prevalence and distribution as emerging pathogens are due to the limitations in their detection and identification. This study aimed to determine the presence and the identification of Arcobacter in chicken breast samples commercially retailed in San José, Costa Rica, as well as to describe the adherence and invasive potential of the strains to human cells (HEp-2). Fifty chicken breast samples were collected from retail markets in the metropolitan area of the country. Six different isolation methodologies were applied for the isolation of Arcobacter. Isolation strategies consisted of combinations of enrichments in de Boer or Houf selective broths and subsequent isolation in blood agar (directly or with a previous passive membrane filtration step) or Arcobacter selective agar. Suspicious colonies were identified with a genus-specific PCR, whereas species-level identification was achieved with a multiplex PCR. The overall isolation frequency of Arcobacter was 56%. From the isolation strategies, the combination of enrichment in Houf selective broth followed by filtration on blood agar showed the best performance, with a sensitivity of 89% and a specificity of 84%. A total of 46 isolates were confirmed as Arcobacter with the genus-specific PCR, from which 27 (59%) corresponded to Arcobacter butzleri, 9 (19%) to Arcobacter cryaerophilus, and 10 (22%) were not identified with this multiplex PCR. Regarding the potential pathogenicity, 75% of the isolates presented adherence to HEp-2 cells, while only 22% were invasive to that cell line. All invasive strains were A. butzleri or nonidentified strains. The results show the presence of potentially pathogenic Arcobacter in poultry and recognize the importance it should receive as a potential foodborne pathogen from public health authorities.
空肠弯曲菌已被确认为潜在的食源性和水源性致病菌。由于其检测和鉴定方法存在局限性，导致缺乏标准化的分离方法，并且对其作为新兴病原体的流行率和分布的了解相对较少。本研究旨在确定哥斯达黎加圣何塞市商业销售的鸡胸肉样本中是否存在空肠弯曲菌，以及鉴定空肠弯曲菌，并描述其对人细胞（HEp-2）的黏附和侵袭潜能。从该国大都市区的零售市场采集了 50 份鸡胸肉样本。应用了六种不同的分离方法来分离空肠弯曲菌。分离策略包括在 de Boer 或 Houf 选择性肉汤中进行富集，然后直接或通过先前的被动膜过滤步骤在血琼脂（blood agar）或空肠弯曲菌选择性琼脂上进行分离。使用属特异性 PCR 鉴定可疑菌落，而种水平的鉴定则通过多重 PCR 实现。空肠弯曲菌的总体分离频率为 56%。在分离策略中，Houf 选择性肉汤富集后过滤到血琼脂上的组合表现出最佳性能，灵敏度为 89%，特异性为 84%。通过属特异性 PCR 确认了 46 株空肠弯曲菌的分离株，其中 27 株（59%）为空肠弯曲菌 butzleri，9 株（19%）为空肠弯曲菌 cryaerophilus，10 株（22%）不能用这种多重 PCR 鉴定。关于潜在的致病性，75%的分离株对 HEp-2 细胞具有黏附性，而只有 22%的分离株对该细胞系具有侵袭性。所有侵袭性菌株均为空肠弯曲菌或未鉴定菌株。结果表明，家禽中存在潜在致病性的空肠弯曲菌，并认识到从公共卫生当局的角度来看，它作为潜在的食源性致病菌应受到重视。
