血流感染患者分离的肺炎克雷伯菌高毒力荚膜型和毒力基因分析  

Capsular serotypes and virulence genes of Klebsiella pneumoniae in patients with bloodstream infection

作　　者：余倩[1] 李静[1] 李妍淳[1] 田彬[1] 胡志东[1] 

机构地区：[1]天津医科大学总医院医学检验科,天津300052

出　　处：《临床检验杂志》2015年第10期785-788,共4页Chinese Journal of Clinical Laboratory Science

摘　　要：目的研究社区获得性血流感染肺炎克雷伯菌(CAK)与医院获得性血流感染肺炎克雷伯菌(HAK)、高黏液表型肺炎克雷伯菌(HMVKP)与普通肺炎克雷伯菌(CKP)主要荚膜血清型、毒力基因的差异,并探讨毒力因子与产超广谱β内酰胺酶(ESBL)的关系。方法收集2014年1月至2015年1月分离于临床血流感染患者肺炎克雷伯菌41株,利用拉丝试验检测高黏液(HMV)表型,PCR方法及基因测序检测主要荚膜型和毒力基因,Vitek 2 Compact系统进行菌株耐药性检测。结果 17株(41.5%)拉丝试验阳性;主要荚膜分型K1型8株(19.5%),K2型5株(12.2%),K57型3株(7.3%),3类荚膜血清型共占39.0%;黏液表型编码基因A(rmp A)阳性19株(46.3%),其中16株HMV表型阳性;20株菌需氧菌素基因aerobactin阳性,其中19株rmp A阳性。CAK与HAK的HMV表型(65%/19%)、rmp A(70%/2.38%)、aerobactin(70%/28.6%)阳性率差异具有统计学意义(P<0.05)。HMVKP与CKP的荚膜血清型K1(35.29%/8.33%)、毒力基因rmp A(94.12%/12.5%)和aerobactin(94.12%/16.67%)阳性率差异具有统计学意义(P<0.05)。CKP耐药情况较HMVKP严重。非产ESBL菌株较产ESBL菌株的HMV表型、高毒力荚膜型K1/K2/K57及毒力基因rmp A和aerobactin的阳性率高,差异具有统计学意义。结论高毒力荚膜血清型、毒力基因主要见于CAK,且HMV表型菌株携带更多的毒力因子,这类菌株大多为非产ESBL的敏感株。Objective To investigate the difference of capsular serotype,virulence gene between community-acquired bacteremia Klebsiella pneumoniae and,hospital acquired bacteremia-Klebsiella pneumoniae,hypermucoviscosity（ HMV） phenotype Klebsiella pneumoniae,classic Klebsiella pneumoniae and the relationship between virulence factors and extended-spectrum beta-lactamase（ ESBL）.Methods Forty-one of K. pneumoniae isolates were collected from the patients with bacteremia from January 2014 to January 2015.HMV phenotype was detected by string-test. The major capsular serotypes and virulence factors were detected by polymerase chain reaction and DNA sequencing. The drug susceptibility was identified with Vitek 2 compact system. Results 17（ 41. 5%） isolates expressed the HMV phenotype. Eight（ 19. 5%）,5（ 12. 2%） and 3（ 7. 3%） in the 41 strains of K. pneumoniae belonged to K1,K2 and K57 capsular serotype. The positive strain of virulence gene rmp A was found in 19 strains（ 46. 3%）,in which 16 were HMV phenotype. The positive strain of aerobactin was found in 20 strains,in which 19 were also positive rmp A. The expressions of HMV phenotype,rmp A and aerobactin in community-acquire bacteremia K. pneumoniae were significantly higher than those in hospital-acquire bacteremia K. pneumoniae（ P 0. 05）. There were significant differences between HMV strains and classic K. pneumoniae in capsular serotype K1,rmp A and aerobactin（ P 0. 05）. The drug resistance situation of classic K. pneumoniae was much more serious. The positive rates of HMV phenotype,K1 / K2 / K57 and rmp A,aerobactin were higher in non-ESBL producing strains than those in ESBL producing strains. Conclusion High virulence capsular serotypes and virulence genes were more common in community-acquire bacteremia K. pneumoniae,and hypermucoviscosity strains may carry more virulence factors,most of which were non-ESBL producing strains.

关 键 词：毒力 肺炎克雷伯菌 黏液 

分 类 号：R446.5[医药卫生—诊断学]