Avaliação de biomarcadores salivares para diagnóstico de transtorno de espectro autista por espectroscopia ATR-FTIR

Abstract

Introduction: Autistic Spectrum Disorder (ASD) is a neurodevelopmental syndrome diagnosed by clinical observations and behavioral assessments. Currently, diagnostic methods based on biomarkers are lacking, making the development of accurate and appropriate diagnostic tools for ASD a challenge. The reduction in waiting time for the diagnosis of ASD can anticipate the beginning of interventions, providing better results. Therefore, the search for an economic, non-invasive, sustainable (without reagents) and accurate diagnostic platform is relevant to the diagnosis of ASD. Objective: Establish salivary infrared spectral signature in the TEA that allows the development of diagnostic platforms based on Attenuated Total Reflectance–Fourier Transform Infrared (ATR-FTIR) spectroscopy system. Material and methods: This study was approved by the Research Ethics Committee (CEP) in human beings at the Federal University of Uberlândia (UFU) and analyzed the salivary profile of 53 participants, 19 diagnosed with ASD and 34 neurotypical (NT), with ages between 2 and 20 years, using ATR-FTIR spectroscopy in regions with an electromagnetic spectrum between 4000 cm-1 and 400 cm-1. The sensitivity and specificity of the vibrational modes were evaluated using the Receiver Operating Characteristic (ROC) curve. Results: Three salivary vibrational modes in the ASD group were differentially expressed (p <0.05) compared to NT. These vibrational modes have been pre-validated as potential spectral diagnostic biomarkers by analyzing the ROC curve. The band area of the 2935 vibrational mode (2942 - 2895 cm-1) showed a sensitivity of 73.68% and specificity of 79.41% (p = 0.012) compared with the NT, and accuracy of 76.5%. The areas of the band in the 1636 vibrational mode (1738 - 1581 cm-1) of the ASD group showed a sensitivity of 68.42% and specificity of 73.53% (p = 0.0032) compared to the NT area, and of the vibrational mode 986 ( 1005 - 959 cm-1) exhibited a sensitivity of 50% and specificity of 73.68% (p = 0.0493). Conclusion: The salivary spectral biomarkers discovered using univariate analysis can support a new robust alternative for the complementary diagnosis of ASD from a sustainable technology platform, with an ultrasmall sample volume, non-invasive collection and without the use of reagents, which contributes for making medical decisions and favors the beginning of the indicated intervention. Keywords: Autism spectrum disorder. Saliva. Biomarkers. Fourier transform infrared spectroscopy. Diagnosis.