ABSTRACT
Objective To investigate the genetic homology in clinical isolates of extensively drug-resistant Acinetobacter baumannii (XDRAB),so as to provide evidence for better controlling hospital infections.Methods The genotypes of 28 clinical XDRAB isolates were determined by Enterobacterial Repetitive Intergenic Consensus PCR (ERIC-PCR).PCR was conducted to analyze 9 types of β-lactamase genes (blaKPC,blaIMP,blaVIM,blaNDM-1,blaOXA-23,blaOXA-24,blaOXA-48, blaOXA-51 and blaOXA-58),the outer membrane porin gene (CarO)and insertion sequence (IS)ISAba1.We also carried out linkage analysis for ISAba1-OXA23 and ISAba1-OXA58.Results Most of the above 28 XDRAB strains were isolated from respiratory tract specimens from intensive care patients.The result of ERIC-PCR showed that there was high homology between all the strains,suggesting that they might derive from the same clone.The genes blaOXA-23,blaOXA-51,CarO and the IS ISAba1 except Class Bβ-lactamase genes,blaOXA-24,blaOXA-48,blaOXA-58,ISAba1-OXA23 and ISAba1-OXA58 were detected in all the clinical strains by PCR.Conclusions All the XDRAB isolates belong to the same clone and carry the same drug-resistant genes,indicating that there was clone spread among XDRAB isolates.
ABSTRACT
Objective To estimate the application value of a standard operating procedure (SOP) in the detection of syphilitic anticardiolipin reagin. Methods Clinical laboratories from 9 local hospitals in Shanghai participated the program. Quality control samples with unknown target value were qualitatively and quantitatively examined according to the uniform SOP in these laboratories with the same reagent and facility of horizontal reaction. External quality assessment (EQA) was carried out by using seven serum samples with no, or low (1∶ 128 dilution) to high (1∶1 dilution) concentrations of target before and after the implementation of SOP. The test results were statistically analyzed and the reasons for the detecting error were assessed. Results A total of 388 tests were performed in the 9 clinical laboratories. The total accuracy rate was 93.0%, including 40.2% in the detection of samples with 1 ∶ 8 dilution of target, 49.2% in the detection of samples with 1 ∶ 16 dilution of target, and 3.6% in the detection of samples with 1 ∶ 32 dilution of target. No forward bias was observed in these tests. There was a significant difference in the accuracy rate between the two times of EQA before and after the implementation of SOP (x2 = 4.17, P < 0.05). Conclusions The improved standard procedure for nontreponemal antigen test is beneficial to the decrease of testing error, and may provide a basis for the establishment of SOP and implementation of internal quality assessment.