Towards Point of Care Diagnostics: Visual Detection of Meningitis Pathogens Directly from Cerebrospinal Fluid

摘要

Rapid and cost-efficient methods for diagnostics of infectious diseases can expedite prescription of adequate treatment,thus shortening the patients'recovery and reducing adverse side effects.In this study,we developed a procedure for visual detection of bacterial pathogens Gram-negative Neisseria meningitidis and Gram-positive Streptococcus pneumoniae directly from human samples of cerebrospinal fluid(CSF).The assay uses hybridization probes that can efficiently recognize folded single-stranded DNA analytes due to their split design.The assay includes the following stages: PCR amplification of N.meningitidis and S.pneumoniae targeted sequences;λ exonuclease treatment of the polymerase chain reaction(PCR)amplicons,and detection of the amplicons by hybridization probes with visual signal output.The assay requires 2.0 h with hands-on time of about 40 min,and a regular PCR thermal cycler.It detects down to 10 bacteria in 2 μL of cerebrospinal fluid.The assay works for both gram-positive and gramnegative bacteria and does not require optimization of PCR conditions.This development creates a basis for the point-ofcare diagnostics of bacterial meningitis with visual signal output.