Utilization of Raman spectroscopy for identification and characterization of fungal pathogens

Abstract

Rapid and accurate identification of pathogens causing infections is one of the biggest challenges of medicine. Timely identification and characterization of fungal pathogens is essential for choosing a suitable tailored antifungal treatment and proper management of patients. This, in turn, leads to the shortening of hospital stays, reducing costs and time to adequate treatment, increasing the well-being of patients, limiting the spread of antifungal resistance, and helps to save the lives of many patients. Raman spectra allow the assessment of the overall molecular constitution of biological samples, based on specific signals from proteins, nucleic acids, lipids, carbohydrates, and inorganic crystals. It has been found to be a valuable tool for the identification of microorganisms, characterization of virulence factors, and their ability to form biofilms. The most used method in current diagnostic laboratories for fungal identification is fungal culture which can take four weeks or longer to maximize the recovery of slowly growing fungi. This needs the development of new methods to detect and identify these pathogens directly from clinical samples.

We aim to offer an evidence-based review of the Raman spectroscopy technique, its strengths, and limitations with respect to its use in the field of medical mycology to help in the early detection of fungal pathogens. Raman spectroscopy can be used not only for identification but, also for the biochemical analysis of the fungal pathogen. It is a precise, convenient, and low-cost method for fungal detection. Analysis of various cell organelles present in the fungal cell can help us understand the cell dynamics and enable us to study the reaction of those cells under different environmental stresses. It can also help us to further study mechanisms of antifungal resistance.