Correlation between MEST-C score in kidney biopsy of IgA nephropathy patients with prognosis

Abstract

Introduction: IgA nephropathy (IgAN) is the most common type of primary glomerulonephritis, and is the most common type of glomerulopathy which leading to endstage renal disease (ESRD). Prompt diagnosis of high-risk patients is important to initiate specific treatment early and prevent progression to ESRD. Oxford pathological classification, known as MEST-C score, attempts to predict prognosis based on pathological factors. Objectives: In this study, we evaluated the value of pathological and clinical variables in estimating the prognosis of IgAN in Iranian patients. Patients and Methods: In this retrospective cohort study, 165 specimens were reviewed by a nephropathologist, who reported the MEST-C score after the definitive diagnosis of IgAN. Patient records were reviewed to gather clinical data, including serum creatinine, 24-hour urine protein levels, diagnosis of hypertension and/or diabetes, and any treatment received. The pre-specified endpoints were determined as progression to ESRD, a reduction in estimated glomerular filtration rate (eGFR) to less than 50% of its baseline, performance of renal transplant, or death. The variables were compared in patients who had reached the prespecified endpoints and those who had not, to estimate their prognostic value. Results: Findings showed that the urinary protein level and T-score on biopsy were significant prognostic factors. Other pathological factors such as C, S, and M scores lost their significance on multivariate analysis. Further research is needed to validate the efficacy of the MEST- C score in different racial populations. Conclusion: In our study, urinary protein level at diagnosis and T-score on biopsy were validated as prognostic factors, while M, E, S and C scores were not deemed significant. Further research is necessary to validate the MEST-C scoring system in different populations before its use in routine clinical practice.