The establishment of a standard and real patient kidney stone library utilizing Fourier transform-infrared spectroscopy with a diamond ATR accessory.

Abstract

This investigation highlights the establishment of a real patient kidney stone library utilizing Fourier transform-infrared spectroscopy with a diamond attenuated total reflection accessory (FT-IR ATR) and the construction of a standard FT-IR ATR (sFTIRATR) library using OMNIC spectral math arithmetic operations for kidney stone analysis. This is necessary because reference spectra in commercial libraries provided with specialized software are usually complied using synthesized crystalline compounds which can exhibit changes in intensity, position and/or characteristic profile of reflectance bands when compared with authentic biological stone compositions. Currently, there is no published literature for the Republic of Ireland (RoI) on stone type and prevalence. The results obtained from the establishment of the real patient kidney stone library were a representative selection of kidney stones found in the population, and thereby provided an accurate picture of the present epidemiology of kidney stones in the RoI. The results of 188 patients were compared with those from our newly constructed sFTIRATR library and existing methods, namely wet chemical analysis, and FT-IR ATR utilizing an ATR algorithm and potassium bromide search libraries. We found that for the optimum quantitative analysis of kidney stone mixtures, FT-IR ATR spectroscopy utilizing a standard FT-IR ATR library, supported by a real patient kidney stone library, applying library searching accurately provides the molecular and crystalline species of stone constituents present in an unknown kidney stone sample, providing some predicative value in diagnosing medical conditions. Our data suggest that the epidemiology for nephrolithiasis in the RoI is similar to other Western nations.