{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,1]],"date-time":"2026-10-01T12:31:02Z","timestamp":1790857862480,"version":"4.1.0"},"reference-count":17,"publisher":"MDPI AG","issue":"17","license":[{"start":{"date-parts":[[2024,8,29]],"date-time":"2024-08-29T00:00:00Z","timestamp":1724889600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>Amyloidosis diagnosis relies on Congo red staining with immunohistochemistry and immunofluorescence for subtyping but lacks sensitivity and specificity. Laser-microdissection mass spectroscopy offers better accuracy but is complex and requires extensive sample preparation. Attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectroscopy offers a promising alternative for amyloidosis characterization. Cardiac tissue sections from nine patients with amyloidosis and 20 heart transplant recipients were analyzed using ATR-FTIR spectroscopy. Partial least squares discriminant analysis (PLS-DA), principal component analysis (PCA), and hierarchical cluster analysis (HCA) models were used to differentiate healthy post-transplant cardiac tissue from amyloidosis samples and identify amyloidosis subtypes [\u03ba light chain (n = 1), \u03bb light chain (n = 3), and transthyretin (n = 5)]. Leave-one-out cross-validation (LOOCV) was employed to assess the performance of the PLS-DA model. Significant spectral differences were found in the 1700\u20131500 cm\u22121 and 1300\u20131200 cm\u22121 regions, primarily related to proteins. The PLS-DA model explained 85.8% of the variance, showing clear clustering between groups. PCA in the 1712\u20131711 cm\u22121, 1666\u20131646 cm\u22121, and 1385\u20131383 cm\u22121 regions also identified two clear clusters. The PCA and the HCA model in the 1646\u20131642 cm\u22121 region distinguished \u03ba light chain, \u03bb light chain, and transthyretin cases. This pilot study suggests ATR-FTIR spectroscopy as a novel, non-destructive, rapid, and inexpensive tool for diagnosing and subtyping amyloidosis. This study was limited by a small dataset and variability in measurements across different instruments and laboratories. The PLS-DA model\u2019s performance may suffer from overfitting and class imbalance. Larger, more diverse datasets are needed for validation.<\/jats:p>","DOI":"10.3390\/ijms25179358","type":"journal-article","created":{"date-parts":[[2024,8,29]],"date-time":"2024-08-29T03:40:39Z","timestamp":1724902839000},"page":"9358","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":5,"title":["Pilot Study on the Use of Attenuated Total Reflectance-Fourier Transform Infrared Spectroscopy for Diagnosing and Characterizing Cardiac Amyloidosis"],"prefix":"10.3390","volume":"25","author":[{"given":"Charlotte","family":"Delrue","sequence":"first","affiliation":[{"name":"Department of Nephrology, Ghent University Hospital, 9000 Ghent, Belgium"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Annelore","family":"Vandendriessche","sequence":"additional","affiliation":[{"name":"Department of Pathology, Ghent University Hospital, 9000 Ghent, Belgium"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Am\u00e9lie","family":"Dendooven","sequence":"additional","affiliation":[{"name":"Department of Pathology, Ghent University Hospital, 9000 Ghent, Belgium"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mala\u00efka","family":"Van der Linden","sequence":"additional","affiliation":[{"name":"Department of Pathology, Ghent University Hospital, 9000 Ghent, Belgium"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9183-4390","authenticated-orcid":false,"given":"Marijn M.","family":"Speeckaert","sequence":"additional","affiliation":[{"name":"Department of Nephrology, Ghent University Hospital, 9000 Ghent, Belgium"},{"name":"Research Foundation-Flanders (FWO), 1000 Brussels, Belgium"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sander","family":"De Bruyne","sequence":"additional","affiliation":[{"name":"Department of Diagnostic Sciences, Ghent University, 9000 Ghent, Belgium"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2024,8,29]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1323","DOI":"10.1016\/j.jacc.2016.06.053","article-title":"AL (Light-Chain) Cardiac Amyloidosis","volume":"68","author":"Falk","year":"2016","journal-title":"J. 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