Laboratory of Bacteriology, Department of Microbiology, Center of Biological Sciences, Universidade Estadual de Londrina, Londrina, Brazil.
Laboratory of Avian Medicine, Department of Preventive Veterinary Medicine, Agricultural Sciences Center, Universidade Estadual de Londrina, Londrina, Brazil.
Braz J Microbiol. 2019 Jul;50(3):685-694. doi: 10.1007/s42770-019-00086-2. Epub 2019 May 3.
Proteus mirabilis is an opportunistic pathogen often associated with a variety of human infections acquired both in the community and in hospitals. In this context, the present work aimed to evaluate the genotypic and phenotypic characteristics of the virulence factors and antimicrobial resistance determinants of 32 P. mirabilis strains isolated from chicken carcasses in a poultry slaughterhouse in the north of the state of Paraná, Brazil, in order to assess a potential zoonotic risk. The isolates presented a variety of virulence genes that contribute to the development of infection in humans. The mrpA, pmfA, atfA (fimbriae), ireA (siderophores receptor), zapA, ptA (Proteases), and hpmA (hemolysin) genes were found in 32 (100%) isolates and ucaA (fimbriae) in 16 (50%). All isolates showed aggregative adherence in HEp-2 cells and formed biofilms. Of all strains, 27 (84.38%) showed cytotoxic effects in Vero cells. Antimicrobial susceptibility was tested using 20 antimicrobials, in which 25 (78.13%) strains were considered multidrug-resistant. The presence of bla and bla genes conferring resistance to β-lactams and qnr to quinolones were also detected in the isolates after presumption in the phenotypic test, in which 7 (21.88%) isolates contained the CTX-M-2 group, 11 (34.38%) contained CIT group and 19 (59.38%) contained qnrD. Therefore, chicken carcasses contaminated with P. mirabilis may pose a health risk to the consumer, as these isolates have a variety of virulence and antimicrobial resistance characteristics that can be found in P. mirabilis strains isolated from human infections.
奇异变形杆菌是一种机会致病菌，常与人类在社区和医院获得的各种感染有关。在这种情况下，本研究旨在评估从巴西巴拉那州北部一家家禽屠宰场的鸡胴体中分离的 32 株奇异变形杆菌的毒力因子和抗菌药物耐药决定因子的基因型和表型特征，以评估潜在的人畜共患病风险。这些分离株表现出多种有助于人类感染发展的毒力基因。在 32 株（100%）分离株中发现了 mrpA、pmfA、atfA（菌毛）、ireA（铁载体受体）、zapA、ptA（蛋白酶）和 hpmA（溶血素）基因，而 ucaA（菌毛）基因则在 16 株（50%）分离株中发现。所有分离株在 HEp-2 细胞中均表现出聚集性黏附，并形成生物膜。在所有菌株中，27 株（84.38%）对 Vero 细胞表现出细胞毒性作用。使用 20 种抗生素进行了药敏试验，其中 27 株（78.13%）被认为是多重耐药菌。在表型试验中推测存在 bla 和 bla 基因，这些基因赋予了对β-内酰胺类和喹诺酮类的耐药性，还在分离株中检测到 qnr 基因，其中 7 株（21.88%）分离株含有 CTX-M-2 组，11 株（34.38%）含有 CIT 组，19 株（59.38%）含有 qnrD。因此，受奇异变形杆菌污染的鸡胴体可能对消费者的健康构成威胁，因为这些分离株具有多种毒力和抗菌药物耐药特征，这些特征也可以在人类感染中分离到奇异变形杆菌。
