猪传染性胸膜肺炎放线杆菌的鉴定和耐药性研究

猪传染性胸膜肺炎是由猪传染性胸膜肺炎放线杆菌(Actinobacillus pleuralpneumoniae，APP)引起的一种高度传染性呼吸道疾病，临床上准确鉴定该病原菌并合理选择抗生素施药十分重要。研究比较了应用传统方法、PCR方法和MALDI TOF方法鉴定45株临床APP，并比较了三种优势血清型的毒力表型，最后测定了其对临床34种常见抗生素的MIC。结果发现MALDI TOF微生物学鉴定方法具有快速、准确的优势；临床菌株血清型主要包括3型（20株）、1型（13株）、7型（7株），其他血清型菌株5株，其中1型毒力最强；APP对罗红霉素、头孢噻呋、恩诺沙星、氨苄西林等高度敏感，对四环素、土霉素等耐药率较高。研究为临床快速鉴定APP和合理选择用药提供了参考依据，为APP临床耐药折点的制定奠定了基础。

Identification and Antimicrobial Resistance of Actinobacillus pleuralpneumoniae

Actinobacillus pleuralpneumoniae (APP) is the causative agent of porcine contagious pleuropneumonia, a highly contagious respiratory disease in pigs. With the severe situation of clinical bacterial resistance, it is very important to accurately identify the pathogen and rationally select antibiotics in clinical practice. Traditional methods, PCR assay and MALDI TOF method were used to identify APP, and the virulence was evaluated amongst isolates from three predominant serotypes. Lastly, the MICs of 34 common antibiotics in clinical practice were determined. The results showed that the MALDI TOF was more rapid and accurate than other methods. The serotypes of clinical strains mainly included type 3 (20 strains), type 1 (13 strains), type 7 (7 strains), and other serotype (5 strains). Among which, type 1 was the most virulent. MIC test showed that APP was sensitive to roxithromycin, ceftiofur, enrofloxacin, ampicillin, etc, and resistant to tetracycline and oxytetracycline. Therefore, this study provided a reference for clinical rapid identification of APP and rational selection of antimicrobial agents, and a foundation for the development of APP clinical breakpoints.