粪便中分离肺炎克雷伯菌的血清型与毒力基因检测

目的了解粪便标本分离肺炎克雷伯菌（KPN）的血清型与毒力基因分布，为临床治疗提供依据。方法收集2013年11月—2014年6月某院健康体检者及住院非腹泻患者粪便标本分离KPN，检测其黏液表型、 6种荚膜血清型（K1、K2、K3、K5、K54和K57)及6种毒力基因（rmpA、fimH、Aero、mrkA、wabG和ironB），分析不同黏液表型、不同人群来源菌株荚膜血清型与毒力基因分布情况。结果收集粪便标本510份，其中健康体检者92份，住院非腹泻患者418份，分离KPN 107株（健康体检者19株，住院非腹泻患者88株），粪便标本KPN总分离率为20.98%，其中高黏液表型菌24株，非高黏液表型菌83株。分离的KPN中6种血清型和6种毒力基因均有检出，以K1、K2、K57、K54血清型为主(48.60%)；毒力基因mrkA和wabG检出率最高（分别为90.65%、83.18%），rmpA+fimH+Aero +mrkA +wabG基因同时检出最常见（30.84%），主要分布于K1、K2、K57、K54血清型中。rmpA和Aero毒力基因主要在K1、K2、K57、K54血清型中检出。健康体检者KPN血清型以K1型为主（26.32%），未检测到K3和K57型；住院非腹泻患者6种血清型均有检出，以K1、K2、K57、K54为主。高黏液表型菌同时携带4种毒力基因以上者占83.33%（20/24），高于非高黏液表型菌的32.53%（27/83）（χ2=19.51，P＜0.01）。高黏液表型菌中K1、K2、K57、K54血清型总检出率为91.67%（22/24），高于非高黏液表型菌的36.14%（30/83）； rmpA、Aero毒力基因的检出率均为95.83%，均高于非高黏液表型菌组（分别为31.32%、30.12%）（均P＜0.05）。结论粪便中分离的KPN均检测到强毒力荚膜血清型和多种毒力基因，尤其在高黏液表型菌和住院患者分离菌中，应引起临床重视。

Detection of serotypes and virulence genes of Klebsiella pneumoniae from feces

ObjectiveTo understand the distribution of serotypes and virulence genes of Klebsiella pneumoniae(KPN) isolated from feces specimens, and provide basis for clinical treatment. MethodsKPN isolated from feces specimens of healthy physical examination people and hospitalized patients without diarrhea in a hospital between November 2013 and June 2014 were collected. Mucoid phenotype, 6 kinds of capsule serotypes（K1, K2, K3, K5, K54, and K57), and 6 kinds of virulence genes （rmpA, fimH, Aero, mrkA, wabG, and ironB）were detected, distribution of capsule serotypes and virulence genes in KPN of different mucoid phenotypes and from different populations were analyzed. ResultsA total of 510 feces specimens were collected, 92 were from healthy physical examination people and 418 from hospitalized patients without diarrhea, 107 strains of KPN were isolated ( 19 from healthy physical examination people, and 88 from hospitalized patients without diarrhea),the total isolation rate of KPN from feces specimens was 20.98%, 24 isolates were hypermucoviscous phenotype KPN (HMVKP) stains, and 83 were non HMVKP strains. 6 kinds of capsule serotypes and 6 kinds of virulence genes were all detected among KPN, the major were K1, K2, K57, and K54 serotypes(48.60%)；the detection rates of virulence genes mrkA and wabG were the highest (90.65% and 83.18% respectively), simultaneous detection of rmpA+fimH+Aero +mrkA +wabG gene was most common (30.84%), which mainly distributed in K1,K2,K57,and K54 serotypes. rmpA and Aero virulence genes were mainly detected in K1,K2,K57,and K54 serotypes. Among healthy physical examination people, the main serotype of KPN was K1 type（26.32%），while K3 and K57 types were not detected; 6 kinds of capsule serotypes were all detected from hospitalized patients without diarrhea, the major types were K1, K2, K57, and K54. HMVKP strains carrying 4 kinds of virulence genes was higher than non HMVKP strains (83.33%［20/24］ vs 32.53%［27/83］, χ2=19.51，P＜0.01). The total detection rate of K1, K2, K57, and K54 serotypes in HMVKP strains were higher than non HMVKP strains (91.67%［22/24］ vs 36.14%［30/83］）； the detection rates of rmpA and Aero genes were both 95.83%, which were higher than those in non HMVKP strains (31.32% and 30.12% respectively)( both P＜0.05）. ConclusionHypervirulence capsular serotypes and multiple virulence genes are detected in KPN from feces, especially HMVKP strains and strains from hospitalized patients, which should be paid attention.