PHASE ANGLE AS A MARKER FOR DIFFERENTIATING ESCHERICHIA COLI AND CANDIDA ALBICANS PATHOGENS

Abstract

Aim: Early diagnosis is important in bacterial and fungal identification in cerebrospinal fluid (CSF), and treatment option varies according to the identified pathogens. Our aim was to separate bacterial and fungal pathogens with minimum colony number in CSF from sterile CSF by 50kHz phase angle (PA) bioimpedance values.

Methods: We evaluated the performance of the 18 Gauge probe for differentiating bacterial and fungal CSF from sterile. An amount of 200µl sterile CSF was used as a standard in each experiment, and it was inoculated with one and two colony of Escherichia coli (E. coli) and Candida albicans (C. albicans) separately.

Results: PA values of CSF samples were compared with each other concerning one and two colony numbers. It was observed that two colony strains of E. coli and C. albicans could be differentiated from sterile CSF using PA values. One colony of the E. coli and C. albicans strains could not be distinguished from each other due to the small diameter of E. coli. Furthermore, since E. coli has a small diameter, it causes a large extracellular pathway in the environment. Thus, it shows less resistance to the current flow like sterile CSF, so one colony of it has not been differentiated from sterile CSF.

Conclusion: Bioimpedance spectroscopy PA values can provide a predictive approach for differentiating bacterial pathogens from fungal with an inexpensive, simple, and time-saving way in CSF samples with minimal colony number.