Investigation of Bacterial Presence in Cerebrospinal Fluid by Bioimpedance Technique

Abstract

Objective: This study aimed to determine the presence of bacteria and their colony numbers in cerebrospinal fluid (CSF) bybioimpedance measurements at 50 kHz phase angle (PA) and 5 kHz impedance values.Methods: We evaluated the performance of the 18 Gauge probe for detecting several types of bacteria in CSF ex-vivo. Weequally monitored the electrical differentiation between colony numbers. A quantity of 200 µl sterile CSF was used as thestandard in each experiment and was inoculated with 1, 2, 5, and 10 colonies of Coagulase-negative staphylococci, Streptococcus pneumoniae and Acinetobacter baumannii, separately.Results: PA and impedance values of CSF samples were compared with each other concerning different colony numbers. Itwas observed that, varying numbers of colony strains of Acinetobacter baumannii, Coagulase-negative staphylococci, andStreptococcus pneumoniae could be differentiated from sterile CSF using PA and impedance values. Only one colony of the A.baumannii strain could not be distinguished from sterile CSF due to its thin cell wall composition.Conclusion: The bioimpedance probe was time-saving and could detect the presence of bacteria in CSF samples correctly.Moreover, the probe can be used in the rapid detection of bacteria in CSF during real-time examinations.