Assessment of epidemiology and outcomes of adult patients with kidney-limited thrombotic microangiopathies.

Thrombotic microangiopathies (TMA) are usually associated with hematological features (RH-TMA). The epidemiology of TMA limited to kidneys (RL-TMA) is unclear Therefore, patients with TMA and native kidney biopsies were identified during 2009-2022 in 20 French hospitals and results evaluated. RL-TMA was present in 341/757 (45%) patients and associated with lower creatinine levels (median 184 vs 346 µmol/L) than RH-TMA. RL-TMA resulted from virtually all identified causes, more frequently from anti-VEGF treatment and hematological malignancies but less frequently from shigatoxin-associated hemolytic uremic syndrome (HUS), systemic sclerosis, gemcitabine and bacterial infection, and even less frequently when three or more causes/triggers were combined (RL-TMA: 5%; RH-TMA: 12%). RL-TMA was associated with significantly lower major cardiovascular events (10% vs 20%), kidney replacement therapy (23% vs 43%) and death (12% vs 20%) than RH-TMA during follow-up (median 28 months). Atypical HUS (aHUS) was found in 326 patients (RL-TMA: 43%, RH-TMA: 44%). Among the 69 patients with proven complement-mediated aHUS, eculizumab (anti-C5 therapy) was used in 43 (62%) (RL-TMA: 35%; RH-TMA: 71%). Among the 257 other patients with aHUS, including 51% with RL-TMA, eculizumab was used in 29 but with unclear effects of this treatment. Thus, RL-TMA represents a very high proportion of patients with TMA and results from virtually all known causes of TMA and includes 25% of patients with complement-mediated aHUS. Adverse outcomes of RL-TMA are lower compared to RH-TMA but remain significant. Anti-C5 therapy was rarely used in RL-TMA, even in proven complement-mediated aHUS, and its effects remain to be assessed.

Kidney biopsy for the diagnosis and treatment of kidney diseases. Recommendations from the French speaking Society of Nephrology (SFNDT) and French National Authority for Health (HAS) 2022

Kidney Biopsy (KB) is a crucial diagnostic tool in the field of renal diseases and is routinely performed in nephrology departments. A previous survey conducted by the Société Francophone de Néphrologie Dialyse Transplantation (SFNDT) revealed significant disparities in clinical practices, sometimes conflicting with the existing literature and recently published recommendations. In response, the SFNDT wished to promote the development of best practice guidelines, under the auspices of the French National Authority for Health (HAS), to establish a standardized framework for performing kidney biopsies in France.

La biopsie rénale (BR) est un outil diagnostique crucial dans le domaine des maladies rénales et est pratiquée en routine dans les services de néphrologie. Une précédente enquête menée par la Société francophone de néphrologie, dialyse et transplantation (SFNDT) a révélé d'importantes disparités dans les pratiques cliniques, parfois en contradiction avec la littérature existante et les recommandations récemment publiées. En réponse, la SFNDT a souhaité promouvoir l'élaboration de recommandations de bonnes pratiques, sous l'égide de la Haute Autorité de santé (HAS), afin d'établir un cadre standardisé pour la réalisation des biopsies rénales en France.

Bronchiectasis in renal transplant patients: a cross-sectional study.

BACKGROUND: Bronchiectasis is a chronic airway disease characterized by permanent and irreversible abnormal dilatation of bronchi. Several studies have reported the development of bronchiectasis after renal transplantation (RT), but no prospective study specifically assessed bronchiectasis in this population. This study aimed to compare features of patients with bronchiectasis associated with RT to those with idiopathic bronchiectasis. METHODS: Nineteen patients with bronchiectasis associated with RT (RT-B group) and 23 patients with idiopathic bronchiectasis (IB group) were prospectively included in this monocentric cross-sectional study. All patients underwent clinical, functional, laboratory, and CT scan assessments. Sputum was collected from 25 patients (n = 11 with RT-B and n = 14 with IB) and airway microbiota was analyzed using an extended microbiological culture. RESULTS: Dyspnea (≥ 2 on mMRC scale), number of exacerbations, pulmonary function tests, total bronchiectasis score, severity and prognosis scores (FACED and E-FACED), and quality of life scores (SGRQ and MOS SF-36) were similar in the RT-B and IB groups. By contrast, chronic cough was less frequent in the RT-B group than in the IB group (68% vs. 96%, p = 0.03). The prevalence and diversity of the airway microbiota in sputum were similar in the two groups. CONCLUSION: Clinical, functional, thoracic CT scan, and microbiological characteristics of bronchiectasis are overall similar in patients with IB and RT-B. These results highlight that in RT patients, chronic respiratory symptoms and/or airway infections should lead to consider the diagnosis of bronchiectasis. Further studies are required to better characterize the pathophysiology of RT-B including airway microbiota, its incidence, and impact on therapeutic management.

To what extent does freezing impact the mid-infrared signature of urine? Case of patients attending urology department.

Urine is a very interesting and attractive biofluid for biomarker discovery and medical diagnosis research due to its non-invasiveness collection and richness of potential biomarkers. Fourier-Transform Infrared (FTIR) spectroscopy applied on urine samples is a promising tool that could be used as a screening method for various diseases. However, during method development, frozen urine is more accessible, especially for inter-laboratory studies, whereas in routine application fresh urine is more convenient. Here, the objective of our work is to evaluate the freezing impact on mid-infrared signature of urine samples. Therefore, both fresh and frozen urine samples from twenty patients were analysed in a dried form. These samples were collected from patients consulting for cystoscopy examination. Simultaneously, centrifugation was also conducted on 10 of all included patients. Principal component analysis (PCA) revealed that patient inter-variabilities are higher than variability due to the freezing step. Then, Euclidean distance between fresh and frozen urine of each patient highlighted that the impact of freezing is different from one patient to another. Adding the centrifugation step slightly minimized intra-patient variability compared to not centrifugated samples. This study contributes to define experimental conditions for urine analysis development for translational application in biomedical field.

VNtyper enables accurate alignment-free genotyping of MUC1 coding VNTR using short-read sequencing data in autosomal dominant tubulointerstitial kidney disease.

The human genome comprises approximately 3% of tandem repeats with variable length (VNTR), a few of which have been linked to human rare diseases. Autosomal dominant tubulointerstitial kidney disease-MUC1 (ADTKD-MUC1) is caused by specific frameshift variants in the coding VNTR of the MUC1 gene. Calling variants from VNTR using short-read sequencing (SRS) is challenging due to poor read mappability. We developed a computational pipeline, VNtyper, for reliable detection of MUC1 VNTR pathogenic variants and demonstrated its clinical utility in two distinct cohorts: (1) a historical cohort including 108 families with ADTKD and (2) a replication naive cohort comprising 2,910 patients previously tested on a panel of genes involved in monogenic renal diseases. In the historical cohort all cases known to carry pathogenic MUC1 variants were re-identified, and a new 25bp-frameshift insertion in an additional mislaid family was detected. In the replication cohort, we discovered and validated 30 new patients.

Prognostic value of complement serum C3 level and glomerular C3 deposits in anti-glomerular basement membrane disease.

Background and objectives: Activation of the complement system is involved in the pathogenesis of anti-glomerular basement membrane (anti-GBM) disease. Glomerular deposits of complement 3 (C3) are often detected on kidney biopsies. The primary objective of this study was to analyze the prognostic value of the serum C3 level and the presence of C3 glomerular deposits in patients with anti-GBM disease. Methods: We conducted a retrospective cohort study of 150 single-positive patients with anti-GBM disease diagnosed between 1997 and 2017. Patients were categorized according to the serum C3 level (forming a low C3 (C3<1.23 g/L) and a high C3 (C3≥1.23 g/L) groups) and positivity for C3 glomerular staining (forming the C3+ and C3- groups). The main outcomes were kidney survival and patient survival. Results: Of the 150 patients included, 89 (65%) were men. The median [interquartile range (IQR)] age was 45 [26-64]. At diagnosis, kidney involvement was characterized by a median [IQR] peak serum creatinine (SCr) level of 578 [298-977] µmol/L, and 106 (71%) patients required dialysis. Patients in the low C3 group (72 patients) had more severe kidney disease at presentation, as characterized by higher prevalences of oligoanuria, peak SCr ≥500 µmol/L (69%, vs. 53% in the high C3 group; p=0.03), nephrotic syndrome (42%, vs. 24%, respectively; p=0.02) and fibrous forms on the kidney biopsy (21%, vs. 8%, respectively; p=0.04). Similarly, we observed a negative association between the presence of C3 glomerular deposits (in 52 (41%) patients) and the prevalence of cellular forms (83%, vs. 58% in the C3- group; p=0.003) and acute tubulo-interstitial lesions (60%, vs. 36% in the C3- group; p=0.007). When considering patients not on dialysis at diagnosis, the kidney survival rate at 12 months was poorer in the C3+ group (50% [25-76], vs. 91% [78-100] in the C3- group; p=0.01), with a hazard ratio [95% confidence interval] of 5.71 [1.13-28.85] (p=0.04, after adjusting for SCr). Conclusion: In patients with anti-GBM disease, a low serum C3 level and the presence of C3 glomerular deposits were associated with more severe disease and histological kidney involvement at diagnosis. In patients not on dialysis at diagnosis, the presence of C3 deposits was associated with worse kidney survival.

Glomerulonephritis with non-Randall-type, non-cryoglobulinaemic monoclonal immunoglobulin G deposits (PGNMID and ITG).

Background: Glomerulonephritis (GN) with non-Randall-type, non-cryoglobulinaemic monoclonal immunoglobulin G deposits encompasses rare diseases [proliferative GN with non-organized deposits (PGNMID) and immunotactoid GN] that cannot be distinguished without ultrastructural analysis by electron microscopy (EM). Methods: Here, we report and analyse the prognosis of 41 EM-proven (PGNMID for 39/41) and 22 non-EM-proven/DNAJB9-negative cases, diagnosed between 2001 and 2019 in 12 French nephrology centres. Results: Median (interquartile range) serum creatinine (SCr) at presentation was 150 (92-256) µmol/L. The predominant histological pattern was membranoproliferative GN (79%), with IgG3 (74%) kappa (78%) deposits the most frequently observed. Disease presentation and patient management were similar between EM-proven and non-EM-proven cases. A serum monoclonal spike was detected for 21 patients and 10 had an underlying haematological malignancy. First-line therapy was mixed between clone-targeted therapy (n = 33), corticosteroids (n = 9) and RAAS inhibitors (n = 19). After 6 months, nine patients achieved complete and 23 partial renal recovery. In univariate analysis, renal recovery was associated with baseline SCr (odds ratio 0.70, P = 0.07). After a median follow-up of 52 (35-74) months, 38% of patients had progressed to end-stage kidney disease independently associated with baseline SCr [hazard ratio (HR) 1.41, P = 0.003] and glomerular crescentic proliferation (HR 4.38, P = 0.004). Conclusions: Our results confirm that non-cryoglobulinaemic and non-Randall GN with monoclonal IgG deposits are rarely associated with haematological malignancy. The prognosis is uncertain but may be improved by early introduction of a specific therapy.

Renal diseases secondary to interferon-ß treatment: a multicentre clinico-pathological study and systematic literature review.

Background: The spectrum of interferon-ß (IFN-ß)-associated nephropathy remains poorly described and the potential features of this uncommon association remain to be determined. Methods: In this study we retrospectively analysed the clinical, laboratory, histological and therapeutic data of patients with biopsy-proven renal disease in a context of IFN-ß treatment administered for at least 6 months. Results: Eighteen patients (13 women, median age 48 years) with biopsy-proven renal disease occurring during IFN-ß therapy were included. The median exposure to IFN-ß (14 patients were treated with IFN-ß1a and 4 patients with IFN-ß1b) was 67 months (range 23-165 months). The clinical presentation consists in hypertension (HT; 83%), malignant HT (44%), proteinuria (protU) >1 g/g (94%), reduced renal function (78%), biological hallmark suggesting thrombotic microangiopathy (TMA; 61%), oedematous syndrome (17%) or nephritic syndrome (11%). The pathological findings included typical features of isolated TMAs in 11 cases, isolated focal segmental glomerulosclerosis (FSGS) lesions in 2 cases and 5 cases with concomitant TMA and FSGS lesions. An exploration of the alternative complement pathway performed in 10 cases (63%) did not identify mutations in genes that regulate the complement system. The statistical analysis highlighted that the occurrence of IFN-ß-associated TMA was significantly associated with Rebif, with a weekly dose >50 µg and with multiple weekly injections. In all cases, IFN-ß therapy was discontinued. Patients with TMA lesions received other therapies, including corticosteroids (44%), eculizumab (13%) and plasma exchanges (25%). At the end of a 36-month median follow-up, persistent HT and persistent protU were observed in 61% and 22% of patients, respectively. Estimated glomerular filtration rate <60 mL/min/1.73 m2 was present in 61% of patients. Conclusions: IFN-ß-associated nephropathy must be sought in the case of HT and/or protU onset during treatment. When TMA and/or FSGS are observed on renal biopsy, early discontinuation of IFN-ß is essential.

In depth investigation of collagen non-enzymatic glycation by Raman spectroscopy.

Non-enzymatic glycation is a post-translational modification of long-lived matrix proteins such as type I collagen. It occurs during aging and leads to the formation of advanced glycation end-products (AGEs). AGE accumulation is associated with severe complications in chronic and age-related diseases. The assessment of modifications induced by this (patho)physiological process represents an interest in biology and medicine for a better patient care. The objective of our work was to position the interest of Raman spectroscopy in the quantification of collagen glycation. Two types of in vitro glycation were used by incubating collagen samples, at different durations, with ribose or glyoxylic acid; these reducing agents acting on the chemical specificity of the glycation reaction. Glycation efficiency was evaluated by the liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) quantification of carboxymethyllysine (CML) and pentosidine, which are among the most studied AGEs. Raman data were processed by PCA coupled to validity indices and Lasso regression as multivariate analysis tools. Regression models were constructed by considering the LC-MS/MS results as reference values. A marked variability was observed within the Raman datasets making difficult the identification of spectral differences between control and ribose-treated collagen samples. By taking advantage of the chemical specificity of the glyoxylic acid treatment leading to CML formation, on one hand, and the feature selection included in the Lasso algorithm, on the other hand, Raman markers associated with glycation were identified. The assigned vibrations corresponded to modifications of side chains of collagen. In addition, a threshold of CML concentration was determined as quantitative indicator of the applicability of Raman spectroscopy for potential patient follow-up purposes. Although lacking in sensitivity to directly detect AGEs in collagen, Raman spectroscopy allows to highlight the molecular modifications of collagen induced by glycation.

Identification of Neoadjuvant Chemotherapy Response in Muscle-Invasive Bladder Cancer by Fourier-Transform Infrared Micro-Imaging.

BACKGROUND: Neoadjuvant chemotherapy (NAC) improves survival in responder patients. However, for non-responders, the treatment represents an ineffective exposure to chemotherapy and its potential adverse events. Predicting the response to treatment is a major issue in the therapeutic management of patients, particularly for patients with muscle-invasive bladder cancer. METHODS: Tissue samples of trans-urethral resection of bladder tumor collected at the diagnosis time, were analyzed by mid-infrared imaging. A sequence of spectral data processing was implemented for automatic recognition of informative pixels and scoring each pixel according to a continuous scale (from 0 to 10) associated with the response to NAC. The ground truth status of the responder or non-responder was based on histopathological examination of the samples. RESULTS: Although the TMA spots of tumors appeared histologically homogeneous, the infrared approach highlighted spectral heterogeneity. Both the quantification of this heterogeneity and the scoring of the NAC response at the pixel level were used to construct sensitivity and specificity maps from which decision criteria can be extracted to classify cancerous samples. CONCLUSIONS: This proof-of-concept appears as the first to evaluate the potential of the mid-infrared approach for the prediction of response to neoadjuvant chemotherapy in MIBC tissues.

HLA-D and PLA2R1 risk alleles associate with recurrent primary membranous nephropathy in kidney transplant recipients.

Recurrence of primary membranous nephropathy after transplantation occurs in up to 44% of patients and is driven by PLA2R antibody. Here, we asked whether genetic determinants could improve risk prediction. First, we sequenced PLA2R1 and HLA-D loci in 248 patients with primary membranous nephropathy and identified two independent single nucleotide polymorphisms (SNPs) at risk for primary membranous nephropathy at each locus. These were rs9271188 (intergenic between HLA-DRB1 and HLA-DQA1,) and rs9275086 (intergenic between HLA-DQB1 and HLA-DQA2) at the HLA-D locus along with rs6726925 and rs13018963 at the PLA2R1 locus. Then we investigated whether primary membranous nephropathy at-risk variants were associated with recurrence in a retrospective cohort of 105 donor-recipient pairs and a replication cohort of 40 pairs. Seven SNPs located between HLA-DRB1 and HLA-DQA1 in linkage disequilibrium with rs9271188, and three SNPs in the PLA2R1 region predicted recurrence when presented by the donor, but not when presented by the recipient. The two SNPs in the HLA-D region most strongly associated with recurrence (rs9271705 and rs9271550) were confirmed in the replication cohort. A genetic risk score based on the two best predictors at each locus (rs9271705, rs9271550, rs17830558, and rs3828323) identified a group of patients with high risk of recurrence. Thus, our results suggest that the graft contributes to recurrence of primary membranous nephropathy through the disease susceptibility HLA-D and PLA2R1 SNPs in an autoimmune milieu. Further studies are needed before implementation of genetic testing for these in donor selection.

Intra-abdominal hypertension in early post-kidney transplantation period is associated with impaired graft function.

BACKGROUND: Moderate hyperhydration is often achieved in the early post-kidney transplantation period. Whether this strategy could lead to the development of intra-abdominal hypertension (IAH) has never been assessed so far. We aimed to study the incidence of IAH after kidney transplantation and its association with graft function recovery. METHODS: We conducted a prospective monocentric study among patients undergoing kidney transplantation at the University Hospital of Reims between May 2017 and April 2019. Intravesical pressure (IVP) was monitored every 8 h from Day 0 to 3. RESULTS: A total of 107 patients were enrolled. Among 55 patients included in the analysis, 74.5% developed IAH. Body mass index >25 kg/m2 was associated with IAH development {odds ratio [OR] 10.4 [95% confidence interval (CI) 2.0-52.9]; P = 0.005}. A previous history of peritoneal dialysis was protective [OR 0.06 (95% CI 0.01-0.3); P = 0.001]. IAH Grades III and IV occurred in 30.9% of patients and correlated with higher Day 3 creatininaemia (419.6 ± 258.5 versus 232.5 ± 189.4 µmol/L; P = 0.02), higher delayed graft function incidence (41.2 versus 7.9%; P = 0.04), lower Kirchner index measured using scintigraphy (0.47 ± 0.09 versus 0.64 ± 0.09; P = 0.0005) and decreased Day 30 estimated glomerular filtration rate (35.8 ± 18.8 versus 52.5 ± 21.3, P = 0.05). IAH patients had higher fluid balance (P = 0.02). Evolution of IVP correlated with weight gain (P < 0.01) and central venous pressure (P < 0.001). CONCLUSIONS: IAH is frequent after kidney transplantation and IAH Grades III and IV are independently associated with impaired graft function. These results question current haemodynamic objectives and raise for the first time interest in intra-abdominal pressure monitoring in these patients. CLINICAL TRIAL NOTATION: ClinicalTrials.gov identifier: NCT03478176.

Spondyloarthritis-Associated IgA Nephropathy.

INTRODUCTION: IgA nephropathy (IgAN) can be associated with spondyloarthritis (SpA). The course of SpA-associated IgAN remains largely unknown due to the absence of large cohorts. METHODS: This retrospective study included patients with biopsy-proven IgAN and definite SpA. Kidney biopsies were centrally examined and scored according to the IgAN Oxford Classification. Thirty-two patients fulfilled the inclusion criteria, with a male:female ratio of 9:1 and median age of 27 and 37 years at SpA and IgAN diagnosis, respectively. HLA-B27 was positive in 90% of cases, and most patients (60%) presented with ankylosing spondylitis. The mean baseline estimated glomerular filtration rate (eGFR) was 84 ± 26 ml/min per 1.73 m2, and the urine protein-to-creatinine ratio was 0.19 g/mmol. RESULTS: Renal biopsy revealed frequent presence of crescents (33%) and interstitial inflammation (18%). Despite almost constant use of renin-angiotensin system inhibitors, combined with steroids in 13 of 32 patients, renal outcome was particularly poor. After a median follow-up of 5.9 years, 4 patients (12.5%) reached end-stage renal disease and 41% of patients experienced a >50% decrease of eGFR. The mean annual eGFR decline rate was -4.3 ± 6.7 ml/min per 1.73 m2. The risk of reaching class IV or V chronic kidney disease (CKD) stage during follow-up was associated with the presence of hypertension, level of proteinuria, and baseline S- and T-scores of the Oxford. CONCLUSION: SpA-associated IgAN is associated with a poor renal outcome, despite frequent use of steroids. Tumor necrosis factor (TNF)-α blockade did not appear to influence the rate of eGFR decline in this setting.

An extension of the RITUX-ERAH study, multicenter randomized clinical trial comparing rituximab to placebo in acute antibody-mediated rejection after renal transplantation.

The treatment of active antibody-mediated rejection (ABMR) is still a matter of debate, the place of rituximab remaining controversial. The French multicenter double-blind RITUX-ERAH study included 38 patients with ABMR in the first year of renal transplantation. All patients received plasma exchanges, intravenous immunoglobulins, and corticosteroids and were randomly assigned rituximab or placebo infusion at day 5. Additional rituximab infusions were allowed. In the intention-to-treat analysis, 12-month graft survival and renal function were not different between the rituximab and placebo groups. Long-term data are needed to conclude. Evaluation of the 7-year outcomes of the RITUX-ERAH study patients according to the rituximab or placebo treatment received. Eleven patients received placebo and 27 at least one infusion of rituximab. Seven years after ABMR, death-censored kidney allograft survival and renal function were not different between the groups. The evolution of anti-HLA sensitization was similar. There was no statistically significant difference in the incidence of infectious or neoplastic complications, but to be noted, seven cancers developed in six patients treated with rituximab (mean period of 44 months post-ABMR). In this cohort, there was no benefit 7 years after ABMR of rituximab in addition to plasma exchanges, intravenous immunoglobulins, and steroids.

Correction: Towards normalization selection of Raman data in the context of protein glycation: application of validity indices to PCA processed spectra.

Correction for 'Towards normalization selection of Raman data in the context of protein glycation: application of validity indices to PCA processed spectra' by Fatima Alsamad et al., Analyst, 2020, DOI: 10.1039/c9an02155h.

Severe Infection in Anti-Glomerular Basement Membrane Disease: A Retrospective Multicenter French Study.

In patients presenting with anti-glomerular basement membrane (GBM) disease with advanced isolated kidney involvement, the benefit of intensive therapy remains controversial due to adverse events, particularly infection. We aim to describe the burden of severe infections (SI) (requiring hospitalization or intravenous antibiotics) and identify predictive factors of SI in a large cohort of patients with anti-GBM disease. Among the 201 patients (median [IQR] age, 53 [30-71] years) included, 74 had pulmonary involvement and 127 isolated glomerulonephritis. A total of 161 SI occurred in 116 patients during the first year after diagnosis. These infections occurred during the early stage of care (median [IQR] time, 13 [8-19] days after diagnosis) with mainly pulmonary (45%), catheter-associated bacteremia (22%) and urinary tract (21%) infections. In multivariable analysis, positive ANCA (HR [95\% CI] 1.62 [1.07--2.44]; p = 0.02) and age at diagnosis (HR [95% CI] 1.10 [1.00-1.21]; p = 0.047) remained independently associated with SI. Age-adjusted severe infection during the first three months was associated with an increased three-year mortality rate (HR [95% CI] 3.13 [1.24-7.88]; p = 0.01). Thus, SI is a common early complication in anti-GBM disease, particularly in the elderly and those with positive anti-neutrophil cytoplasmic antibodies (ANCA). No significant association was observed between immunosuppressive strategy and occurrence of SI.

Towards normalization selection of Raman data in the context of protein glycation: application of validity indices to PCA processed spectra.

Raman spectroscopy is a candidate technique for diagnosis applications in medicine due to its high molecular specificity. Optimizing the pre-treatment applied for Raman data is important for exploiting Raman signals and ensuring their relevance in medical diagnosis. One of the crucial steps in data pre-processing, normalization, can affect significantly the result interpretation. To select the appropriate normalization method, a strategy based on validity indices (VI) is proposed in this study. VI are based on measuring the quality of data partitioning without involving a full sequence of supervised classification. The approach was tested on Raman data acquired from control and in vitro glycated proteins (albumin and collagen). Protein glycation is a process involved in the molecular ageing of tissues that leads to the formation of products altering the functional and structural properties of proteins. Different methods of normalization were applied on the data sets: integrated intensity of the phenylalanine band, integrated intensity of the amide I band, standard normal variate (SNV), multiplicative signal correction (MSC), and extended multiplicative signal correction (EMSC) that performs simultaneously baseline correction and normalization. Following normalization, principal component analysis (PCA) was applied and VI were calculated from PCA scores resulting from each of the normalization methods mentioned. Based on VI quantitative values, our experiments permit to illustrate the effect of normalization on the data separability of control and glycated samples, and to determine the most appropriate normalization and simultaneously the most discriminant principal components to exploit vibrational information associated with glycation-induced modifications. In parallel, principal component analysis - linear discriminant analysis (PCA-LDA) was carried out for positioning the interest of VI in regard to a common chain of data processing.