Trends of renal diseases in Germany: review of a regional renal biopsy database from 1990 to 2013.

Several renal biopsy registries in Europe have shown geographical and temporal variations in the patterns of renal diseases. However, there is a lack of current data on trends of renal disease in Central Europe.After exclusion of transplant and re-biopsies, the renal biopsy registry of the German RWTH Aachen University Hospital included data of 1208 biopsies over a period of 24 years (1990-2013). Trends in the biopsy rate and diagnosis of glomerular diseases were analysed.The average annual biopsy incidence was 6.1 biopsies per 100 000 population. The frequency of kidney biopsies increased significantly over the years (P < 0.001). Primary glomerulonephritis (GN) accounted for nearly two-thirds (58.4%) of all native kidney biopsies, and immunoglobulin A-nephropathy (IgAN) was the leading histological diagnosis (34.7%) followed by necrotizing GN (RPGN) at 18.7%. IgAN increased 2-fold over the study periods (+195%, P < 0.001). Focal segmental glomerulosclerosis accounted for 6.1% of all diagnoses, and its frequency rose to 3.9-fold (+388%, P < 0.001). Lupus nephritis showed a doubling in incidence (P = 0.0499), while acute tubular necrosis decreased to 3.5-fold (P = 0.0008). All other disease entities failed to exhibit linear trends over time. In children, the most common pathologies were IgAN (26.1%) and minimal change disease (21.7%), whereas RPGN (19.4%) dominated in the group of patients >60 years.IgAN was the most common primary glomerular disease in our centre and its prevalence increased over 24 years.