Distribution of glomerular diseases in Taiwan: preliminary report of National Renal Biopsy Registry–publication on behalf of Taiwan Society of Nephrology

BACKGROUND Despite the development of biomarkers and noninvasive imaging tools, biopsy remains the only method for correctly diagnosing patients with unexplained hematuria, proteinuria and renal failure. Renal biopsy has been performed for several decades in Taiwan; however, a national data registry is still lacking until 2013. METHODS The Renal Biopsy Registry Committee was established within the Taiwan Society of Nephrology in January 2013. A biopsy registry format, including basic demographic data, baseline clinical features, laboratory data, and clinical and pathological diagnosis was developed. Approval from the local institutional review board was obtained in each participating medical center. RESULTS From January 2014 to September 2016, 1445 renal biopsies were identified from 17 medical centers. 53.8% cases were reported in men. After excluding renal transplantation, renal biopsies were commonly performed in patients with primary glomerulonephritis (48.1%), secondary glomerulonephritis (36.2%), followed by tubulointerstitial diseases (12.3%) and vascular nephropathy (3.4%). Among primary glomerulonephritis, IgA nephropathy (26.0%), focal segmental glomerulosclerosis (21.6%), and membranous nephropathy (20.6%) were most frequently diagnosed. Diabetic nephropathy (22.4%) and lupus nephritis (21.8%) were the most common among secondary glomerulonephritis. Patients with minimal change disease and membranous nephropathy had heavier proteinuria than those with focal segmental glomerulosclerosis and IgA nephropathy (P < 0.001). Patients with minimal change disease had higher serum IgM and IgE levels. The most common cause of nephrotic syndrome in primary glomerular disease was membranous nephropathy (28.8%), followed by minimal change disease (28.2%). IgA nephropathy was the leading cause of chronic nephritic syndrome, acute nephritic syndrome, and persistent hematuria. The incidence of primary glomerulonephritis was approximately 2.19 in 100,000/year. CONCLUSIONS This is the first report of the National Renal Biopsy Registry in Taiwan. IgA nephropathy is the most common primary glomerulonephritis, while membranous nephropathy is the most common cause of nephrotic syndrome. Primary glomerulonephritis distribution in Taiwan is slightly different from that in other Asian countries.