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bioRxiv · 10.1101/2022.08.29.505698

Application of RT-LAMP-CRISPR-Cas13a technology to the detection of OXA-48 producing Klebsiella pneumoniae

Ortiz-Cartagena, C.·Blasco, L.·Fernandez-Garcia, L.·Pacios, O.·Bleriot, I.·Lopez Diaz, M.·Fernandez-Cuenca, F.·Canton, R.·Tomas, M.
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Abstract

Carbapenem-resistant pathogens have been recognized as a health concern because of their ability to cause severe infections and because they are difficult to detect in laboratories. Researchers are making great efforts to develop a diagnostic technique with high levels of sensitivity and specificity, as accurate, early diagnosis is required to prevent the spread of these microorganisms and improve the prognosis of patients. In this context, CRISPR-Cas systems are proposed as promising tools for the development of diagnostic techniques due to their high specificity: Cas13 endonuclease discriminates single nucleotide changes and displays collateral activity against single-stranded RNA molecules. This technology is usually combined with isothermal pre-amplification reactions in order to increase the sensitivity of diagnosis. We have developed an RT-LAMP-CRISPR-Cas13a-based assay for the detection of Klebsiella pneumoniae OXA-48 producer strains in clinical samples without the need for RNA extraction. The assay exhibited 100 % specificity, sensitivity, positive predictive value and negative predictive value.

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Ortiz-Cartagena, C., Blasco, L., Fernandez-Garcia, L., Pacios, O., Bleriot, I., Lopez Diaz, M., Fernandez-Cuenca, F., Canton, R., Tomas, M.. 2022-08-29. Application of RT-LAMP-CRISPR-Cas13a technology to the detection of OXA-48 producing Klebsiella pneumoniae. https://doi.org/10.1101/2022.08.29.505698

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