A new multiplex polymerase chain reaction assay for the identification a panel of bacteria involved in bacteremia


1 Department of Microbiology, Isfahan University of Medical Sciences, Isfahan, Iran

2 Nosocomial Infection Research Centre, Isfahan University of Medical Sciences, Isfahan, Iran

3 Department of Microbiology, Pasteur Institute of Iran, Tehran, Iran


Background: Throughout the world, bloodstream infections (BSI s ) are associated with high rates of morbidity and mortality. Rapid pathogens identification is central significance for the outcome of the patient than culture techniques for microbial identification. To develop an end point multiplex PCR to identify a group of bacteria including Enterococcus spp., Pseudomons aeruginosa, Staphylococcus spp., Acinetobacter baumannii, 16S rDNA, and Drosophila Melanogaster were used as internal control (IC).
Materials and Methods: Design of primers was done using Mega4, Allel ID6, Oligo6 and Oligo analyzer softwares. Genetic targets for primer designing and identification of genus Enterococcus spp., Staphylococcus spp., and species of Acinetobacter baumannii, Pseudomons aeruginosa, included the rpoB, rpoB and gyrAsss respectively. Then PCR and multiplex PCR were performed
Results: The intended specificity was obtained for the bacteria, which used in this study and there wasn't seen any unspecific amplification by the multiplex PCR. The test showed a sensitivity ranging from 1 to 100 target copies per reaction depending on the bacterial species.
Conclusions: The presented multiplex PCR offers a rapid and accurate molecular diagnostic tool for simultaneous detection of some pathogenic microorganisms. The IC exists in the multiplex PCR accompanied by other primers in the system, can serve as a simple, cost- effective internal control for the multiplex PCR assay.


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