Epidemiology of biopsy-proven glomerulonephritis in the past 25 years in the North-Eastern area of Romania

Purpose The aim of this retrospective study was: to analyze the epidemiological patterns of the kidney disease based on clinical and histological features in a single-center in the N-E region of Romania, between 2011 and 2019 and to compare the biopsy results with the others periods, as well as the results from other countries. Methods We studied 442 renal biopsies. The indications for renal biopsy were represented by the clinical features: nephrotic syndrome, nephritic syndrome, asymptomatic urinary abnormalities, acute kidney injury, and chronic kidney disease of unknown etiology. Results During the past 8 years, the annual incidence of renal biopsies was constant, albeit this incidence remained lower than in other countries. Nephrotic syndrome was the most common indication for renal biopsy (47.6%). Primary glomerulonephritis (GN) was the most common diagnosis in each of the three periods, followed by secondary GN. Vascular nephropathy and TIN were constant as a proportion from the overall biopsies in each of the three periods. The membranoproliferative GN (24.4%) and membranous nephropathy (MN) (21.9%) were the most prevalent primary GN, while lupus nephritis (LN) was the most common secondary glomerular disease in young female patients (7.5%). Compared to 1994-2004 period, we observed a significant decrease of incidence of focal segmental glomerulosclerosis (FSGS) and mesangial proliferative GN, and a significant increases in the frequency of MN. Conclusion The results of this study show that the GN distribution model was constant in N-E Romania and became similar to that observed in many countries with high socio-economic status.