FTIR microspectroscopy of renal tubules for the identification of diabetic ketoacidosis death

Abstract

Diabetic ketoacidosis (DKA) is a fatal complication that occurs in patients with diabetes mellitus (DM) when there is a severe insulin deficiency. In forensic autopsies, deaths related to DKA usually lack morphological evidence. Therefore, accurate postmortem identification of DKA remains a major challenge in forensic practice. The main aim of this study was to identify DKA in renal tubules by the combination of Fourier transform infrared (FTIR) microspectroscopy and chemometrics. The results of principal component analysis (PCA) showed that the biochemical differences between the renal tubules from the DKA and control groups were mainly due to differences in the structure and content of proteins. Subsequently, partial least squares discriminant analysis (PLS-DA) was used to develop a binary classification model, with diagnostic accuracies of 97.73% and 90.77% for the training set and test set, respectively. The results of PCA and PLS-DA showed that differences in protein structure and content were key to distinguishing DKA from controls. This study demonstrates that the combination of FTIR microspectroscopy and chemometrics can be used to accurately perform postmortem diagnosis of DKA.