ABSTRACT
Objective To investigate the incidences, risk factors, genotypes and epidemiology of community-acquired blood stream infection caused by extended spectrum β-lactamases (ESBLs)-producing Escherichia coli and Klebsiella pneumonia strains and to analyze the sensitivity of those ESBLs producing strains to commonly used antibiotics. Methods Forty-two patients who were diagnosed with community-ac-quired blood stream infection caused by Escherichia coli or Klebsiella pneumonia strains in Sichuan Provincial People′s Hospital were recruited in this study. Disc diffusion method was used for the phenotypic confirmato-ry test of ESBLs. Agar dilution method was performed to measure the antimicrobial susceptibility of the ESBLs-producing strains to 13 clinically commonly used antibiotics. Genotypes of the ESBLs-producing strains were identified by polymerase chain reaction (PCR). Multilocus sequence typing (MLST) was used to analyze the epidemiology of ESBLs-producing strains. Logistic regression analysis was performed to analyze the risk factors for community-acquired blood stream infection. Results The ESBLs-producing Escherichia coli strains accounted for 56. 3% (18 / 32) and the ESBLs-producing Klebsiella pneumoniae strains accounted for 20% (2 / 10). All of the 20 ESBLs-producing strains were sensitive to imipenem, meropenem, ertapen-em, nitrofurantoin and moxalactam. The ESBLs-producing strains sensitive to amikacin, piperacillin-tazobactam and fosfomycin accounted for 95% , 90% and 85% , respectively. Drug resistance rates of the 20 strains to cefotaxime, levofloxacin, ciprofloxacin and cefepime were relatively high accounting for 100% , 80% , 80% and 75% , respectively. Among the 20 ESBLs-producing strains, 7 strains only carried the CTM gene, while the other 13 strains were all positive for two genotypes of ESBLs, mainly identified as TEM+CTM-M-14 and TEM+CTM-15 genotypes. The 18 Escherichia coli strains were classified into 10 ST types, most of which were ST131 type, followed by ST10 and ST38 types. This study indicated that malignant tumor might be a possible risk factor. Conclusion The prevalence of community-acquired blood stream infection caused by ESBLs-producing Escherichia coli strains was becoming increasingly serious. Malignant tumor might be the risk factor associated with the producing of ESBLs in Escherichia coli and Klebsiella pneumonia strains. TEM+CTX-M-14 was the predominant genotype of ESBLs-producing strains and the prevalent clone was ST131 type. Carbapenems and enzyme inhibitor compounds were ideal drugs for the treatment of commu-nity-acquired blood stream infection caused by ESBLs-producing Escherichia coli and Klebsiella pneumonia strains. This study was limited by the small sample size. Therefore, it is necessary to conduct further resear-ches based on a large number of samples.
ABSTRACT
Objective To investigate clinical characteristics of 48 cases verified to be infected with S.suis type 2.Methods 1.All data of 48 cases suffered from S.suis type2 infection were col- lected and analyzed.2.Pathogenic gene of S.suis type 2,Such as cps 2A,mrp,and sly et al.,were verified by PCR.Results 1.Pathogenic gene of S.suis type 2 were same from those patients and swine.Drug sensitivity test were carried on and showed resistance to tetracycline and streptomycin. 2.All 48 cases had history to butchering and/or direct contacting blood plasma composition of suffer- ing from or dead pigs.People with wound in the skin had higher risk to be infected.3.Four clinical types were classified as general,meningitis.Shock and both shock combined meningitis.Mortality rate was 14.58%.Conclusion 1.S.suis type 2 was the pathogen leading to the infections of 48 cases in this study.The swine of suffering from the disease or dead were the origins of the transmis- sion.2.Main route of infection was butchering or/and direct contacting the plasma composition of be- ing ill or dead pigs.No second generation of patients were found.3.The cases with shock should be treated as early as possible.4.Taking antibiotic were rational used seriously in human being and ani- mals.