Use of ATR-FTIR spectroscopy to differentiate between cirrhotic/non-cirrhotic HCV patients

Conventional techniques to diagnose (HCV) and assess non-cirrhotic/cirrhotic status of the patient for appropriate treatment regime are expensive and invasive. Present available diagnostic tests are expensive as they include multiple screening steps. Therefore, there is a need of cost-effective, less time consuming and minimally invasive alternative diagnostic approaches can be used for effective screening. We propose that (ATR-FTIR) in conjunction with (PCA-LDA),(PCA-QDA) and (SVM) multivariate algorithms can be used as a sensitive tool for detection of HCV infection and to assess non-cirrhotic/cirrhotic status of patients.

We used 105 sera samples, of which, 55 were from healthy and 50 were from HCV positive individuals. These 50 HCV positive patients were further classified into cirrhotic and non-cirrhotic categories using serum markers and imaging techniques. These samples were freeze dried prior to spectral acquisition then multivariate data classification algorithms were employed to classify these sample types.

PCA-LDA and SVM model computed the diagnostic accuracy of 100% for detection of HCV infection. To further classify the non-cirrhotic/cirrhotic status of a patient, diagnostic accuracy of 90.91% for PCA-QDA and 100% for SVM was observed. Internal and external validation for SVM based classifications observed 100% sensitivity and specificity. The confusion matrix generated by PCA-LDA model computed the validation and calibration accuracy showed 100% sensitivity and specificity, by using 2 PCs for HCV infected and healthy individuals. However, when the PCA QDA analysis was done to classify the non-cirrhotic sera samples from cirrhotic sera samples the diagnostic accuracy achieved was 90.91% based on 7 PC's. SVM was also employed for classification and developed model showed the best results with 100% sensitivity and specificity when external validation was applied.

This study provides an initial insight that ATR-FTIR spectroscopy in conjugation with multivariate data classification tools holds a potentialnot onlytoeffectively diagnosis HCV infection but also to assess non-cirrhotic/cirrhotic status of patients.