Infrared Spectroscopic Profiling of Volatile Metabolites from Uropathogenic Bacteria: Basic Investigations toward Rapid UTI Diagnostics

Urinary tract infections (UTIs) are among the most common bacterial infections, typically begin in the urethra but capable of rapidly progressing to the bladder and kidneys. Without timely intervention, these infections can lead to renal failure and, in severe cases, multiorgan failure. Current diagnostic methods for identifying bacterial pathogens are often time-consuming, highlighting the need for faster, more efficient detection techniques. Metabolite-based bacterial diagnostics offer a promising alternative, enabling minimally or noninvasive detection without the need for bacterial culture─provided that the metabolic profiles of individual bacterial strains are well characterized. This study investigates ten bacterial species associated with UTIs through the analysis of their volatile metabolites using Fourier-transform infrared (FT-IR) spectroscopy. Numerous spectral features corresponding to distinct metabolites were identified. Within a multidimensional metabolic space, each bacterial strain exhibited a unique volatile metabolite profile, serving as the basis for accurate identification. This approach lays the groundwork for future diagnostic platforms in which FT-IR spectroscopy could serve as a rapid, culture-free analytical tool to detect bacterial pathogens directly from exhaled breath and/or urine.