Abstract Background and Aims Oxidative stress (OS) is known as a disturbance between pro- and antioxidant factors, that may lead to DNA or protein oxidation, resulting in cellular damage. Peroxiredoxins (PRDXs) are enzymes with an antioxidant properties. They play dominant role in regulation of cellular peroxide levels, which is crucial in maintaining organisms’ oxidative balance. PRDXs types 1-5 are involved in the pathophysiology of various diseases (e.g. cancer, inflammatory, or renal). We aim to study their role as a prognostic marker of eGFR changes in IgA nephropathy (IgAN), lupus nephritis (LN) and membranous nephropathy (MN) patients. Method This is a retrospective 5-year-follow-up study of 108 IgAN, MN and LN patients, in whom PRDX 1-5 serum levels were assessed with ELISA in 2017. In 2022, we were able to collect the data out of 80 patients: IgAN (n=36); MN (n=22) and LN (n=22). The remaining 28 were considered as lost-to-follow-up, namely: lack of any medical results within last 2 years (n=23); on dialysis (n=2); after renal transplantation (n=2); deceased (n=1). We classified patients depending on the changes of eGFR (decline/stable/increase; Fig. 1) between baseline and after 5 year follow-up and the PRDX levels (high/medium/low; Table 1). The Mann Whitney-U, Kruskal-Wallis and Chi-Square Test were used for statistical analysis, the p-values <0.05 were considered significant. Results Baseline PRDX measurements indicated, that the mean concentrations of serum PRDX 1-5 differ between the glomerulonephropathies (GN). In 2022, we observed significantly different (P = .012) change of eGFR depending on the GN type. 16/80 individuals had eGFR decline and 75% of them were diagnosed with IgAN. The MN and LN groups had increase of eGFR in the last 5 years in most cases, probably as a result of the treatment. We verified if follow-up eGFR was associated with baseline PRDX levels. The 2022 eGFR differed significantly between the GNs depending on the level of serum PRDX 2, 4 and 5 at baseline (P = .002; P = .009; P = .006, respectively, Table 1). Conclusion Our results showed the link between serum PRDXs concentration and IgAN, MN and LN follow-up. Importantly, selected PRDXs’ might be used to predict eGFR decline, particularly in IgAN and LN.