Patterns of glomerular disease based on 4-year kidney biopsy material analyzed by light microscopy and immunofluorescence: a retrospective single-center analysis in Poland.

The aim of this study was to assess the epidemiology of different patterns of chronic glomerular diseases based on clinical, histopathological and immunofluorescent findings of glomerulonephritis patients hospitalized in the Department of Nephrology, Transplantology and Internal Diseases in Poznan between January 2009 and December 2012. We retrospectively studied 418 patients who had been subjected to renal biopsies. Data on serum creatinine concentration, 24 h proteinuria, arterial hypertension, diabetes mellitus, and histological and immunofluorescent findings were collected. The patients' mean age was 42 ±15. The male sex prevailed (53.1%). Immunoglobulin A nephropathy was the most common finding (18.9%), followed by focal segmental glomerulosclerosis (16.3%), membranous glomerulonephritis (10.1%), lupus nephritis (8.4%), extracapillary glomerulonephritis (3.3%) and membranoproliferative glomerulonephritis (2.6%). In 69 (16.5%) patients the biopsy was non-informative or non-diagnostic. Patients with membranous nephropathy presented the highest frequency of nephrotic syndrome (71.4%), followed by membranoproliferative glomerulonephritis and focal segmental glomerulosclerosis. Combined analysis of the clinical, histopathological and immunofluorescent findings in glomerulonephritis patients based on a single center's data can provide important epidemiological findings.