Development of a Simple DNA Extraction Method and Candida Pan Loop-Mediated Isothermal Amplification Assay for Diagnosis of Candidemia

To reduce the morbidity and mortality of candidemia patients through rapid treatment, the development of a simple, rapid molecular diagnostic method that is based on nucleic acid extraction and is superior to conventional methods for detecting in the blood is necessary. We developed a multiplex Pan/internal control (IC) loop-mediated isothermal amplification (LAMP) assay and a simple DNA extraction boiling protocol using Chelex-100 that could extract yeast DNA in blood within 20 min. The Chelex-100/boiling method for DNA extraction showed comparable efficiency to that of the commercial QIAamp UCP Pathogen Mini Kit using qPCR. In addition, the Pan/IC LAMP assay showed superior sensitivity to that of general Pan and species qPCRs against clinical DNA samples extracted with the QIAamp UCP Pathogen Mini Kit and Chelex-100/boiling method. The Pan/IC LAMP assay followed by Chelex-100/boiling-mediated DNA extraction showed high sensitivity (100%) and specificity (100%) against clinical samples infected with . These results suggest that the Pan/IC LAMP assay could be used as a rapid molecular diagnostic test for candidemia.