Evaluation of Real Time PCR as a Diagnostic Method for Early Detection of Klebsiella pneumoniae Carbapenemase-producing Enterobacteriaceae Infections from Positive Blood Culture
Egyptian Journal of Medical Microbiology • 2019
Publication Information
Authors
Shereen H. Ahmed*, 1Nehad A. Fouad, 2Shaymaa M. Abd El Rahman
Keywords
Not Available
Journal
Egyptian Journal of Medical Microbiology
Publisher
Not Available
Volume
Volume 28
Issue
No.4
Pages
121-126
publication.type
Local
Paper Link
Not Available
Supplementary Materials
Not Available
Abstract
Rapid identification of infection caused by Klebsiella pneumoniae
carbapenemase producing bacteria, is critical for the beginning of appropriate
antimicrobial treatment and ending their spread. Objectives: to study and evaluate RTPCR technology as a rapid method to directly detect KPC-producing Enterobacteriaceae
in positive blood culture bottles. Methodology was: cross sectional study, conducted at
Benha University Hospital. 253 blood culture bottles were incubated in the BD
BACTEC™ 9050 Blood Culture System for up to 5 days, and Gram staining was done
when the bottles were identified as being positive by the Bactec system. All Gramnegative pathogens were subcultured and identified Antimicrobial susceptibilities to
meropenem and imepinem were tested by disc diffusion and interpreted according to The
Clinical and Laboratory Standards Institute guidelines 2014. Klebsiella pneumoniae
carbapenemase producing enterobacteriaceae in positive blood culture bottles was
identified by Real time PCR. Results: out of 253 specimens,235 were positive, 186
(79.1%) were Enterobacteriaceae, 57 isolates (30.6%) of all Enterobacteriaceae isolates
were resistant by disc diffusion test, and real-time Polymerase chain reaction detected
55 isolates (29.6%) as positive for the presence of Klebsiella pneumoniae
carbapenemase gene. The sensitivity of PCR was 96.5%, specificity was 100%,
PPV=100%. NPV= 98.5%, and diagnostic accuracy was 98.9%, in comparison with disc
diffusion as a gold standard test. Conclusion: real time Polymerase chain reaction is a
useful, rapid, sensitive, and specific tool to detect Klebsiella pneumoniae carbapenemase
directly in positive blood culture bottle.
carbapenemase producing bacteria, is critical for the beginning of appropriate
antimicrobial treatment and ending their spread. Objectives: to study and evaluate RTPCR technology as a rapid method to directly detect KPC-producing Enterobacteriaceae
in positive blood culture bottles. Methodology was: cross sectional study, conducted at
Benha University Hospital. 253 blood culture bottles were incubated in the BD
BACTEC™ 9050 Blood Culture System for up to 5 days, and Gram staining was done
when the bottles were identified as being positive by the Bactec system. All Gramnegative pathogens were subcultured and identified Antimicrobial susceptibilities to
meropenem and imepinem were tested by disc diffusion and interpreted according to The
Clinical and Laboratory Standards Institute guidelines 2014. Klebsiella pneumoniae
carbapenemase producing enterobacteriaceae in positive blood culture bottles was
identified by Real time PCR. Results: out of 253 specimens,235 were positive, 186
(79.1%) were Enterobacteriaceae, 57 isolates (30.6%) of all Enterobacteriaceae isolates
were resistant by disc diffusion test, and real-time Polymerase chain reaction detected
55 isolates (29.6%) as positive for the presence of Klebsiella pneumoniae
carbapenemase gene. The sensitivity of PCR was 96.5%, specificity was 100%,
PPV=100%. NPV= 98.5%, and diagnostic accuracy was 98.9%, in comparison with disc
diffusion as a gold standard test. Conclusion: real time Polymerase chain reaction is a
useful, rapid, sensitive, and specific tool to detect Klebsiella pneumoniae carbapenemase
directly in positive blood culture bottle.
Staff Members - Benha University