Introduction and objective: This pilot study aimed to evaluate the feasibility of attenuated total reflectance – Fourier transform infrared spectroscopy (ATR FTIR) as a rapid, non-invasive method for detecting biochemical alterations in the fingernails of paediatric patients with inflammatory bowel disease (IBD). Materials and methods: ATR FTIR spectra were acquired from fingernail clippings obtained from 10 children diagnosed with IBD and from 10 age-matched healthy controls. Spectral analysis focused on characteristic vibrational bands associated with keratin structure, including N–H stretching vibrations, asymmetric CH₂ and CH₃ stretching modes, and symmetric CH₃ vibrations. Results: Comparative spectral analysis revealed subtle but consistent differences between the IBD and control groups. Shifts in bands related to keratinassociated amino acids were observed, particularly in the regions corresponding to N–H and C–H stretching vibrations. The most pronounced difference was detected at 1,745 cm⁻¹, attributed to C = O stretching vibrations, suggesting alterations related to oxidative processes in the fingernails of children with IBD. Conclusions: ATR FTIR spectroscopy demonstrated potential for identifying disease-related biochemical changes in the fingernails of paediatric patients with IBD. The observed spectral differences indicate keratin derangements associated with oxidative stress and visible nail alterations. These preliminary findings justify further investigation of ATR FTIR fingernail analysis in larger cohorts and its potential role in monitoring disease-related biochemical changes and dietary interventions, including antioxidant strategies.

attenuated total reflectance – Fourier transform infrared spectroscopy, children, inflammatory bowel disease, nails