FCGG Renal Biopsy Network: first epidemiological report on pediatric renal diseases Sevasti Karamaria1, Johan De Meester2, Amélie Dendooven3, Elena Levtchenko4, Noel Knops4, Koen Van Hoeck5, Dominique Trouet5, Reiner Mauel6, Ben Sprangers7, Wim Laurens8, Johan Vande Walle1, on behalf of the FCGG – NBVN working group 1 Department of Pediatrics, UZ Gent, Ghent; 2NBVN, Antwerp; 3Pathology Department, UZ Gent, Ghent; 4Department of Pediatrics, UZ Leuven, Leuven; 5Departement of Pediatrics, UZ Antwerpen, Antwerp; 6Department of Pediatrics, UZ Brussel, Brussels; 7Department of Nephrology, UZ Leuven, Leuven; 8Department of Nephrology, AZ Nikolaas, Sint-Niklaas. Objective: In 2016, a regional renal biopsy network was founded as a collaboration between renal pathologists and nephrologists in order to standardize diagnosis and therapy. Uniform renal biopsy request and renal biopsy report forms were introduced, together with a new comprehensive list of renal pathology diagnoses for coding. The 2017-2018 epidemiological data of the pediatric patients (age= 0-17 years) are presented. Methods: Following informed consent and in compliance with GDPR, data registration consists of basic patient and categorical renal data, semi-structured medical information of renal histopathology and the clinical renal disease. Results: In 2017-2018, 92 renal biopsies were reported in pediatric patients or 3.6 per 100,000 pediatric inhabitants per year. Three clinical patterns were equally represented: only proteinuria >1g/day; only hematuria; and combination of proteinuria and hematuria. Acute or chronic renal failure were rare. In the youngest age group (0-5 years; N=26) minimal change disease predominated, followed by Henoch-Schönlein nephritis. The middle age group (6-11 years; N=32) mainly presented with disease characterized by hematuria: IgA nephropathy, Henoch-Schönlein nephritis and Alport’s disease. A more diverse renal disease spectrum was present in the highest age group (12-18 years; N=34): IgA nephropathy, different forms of ...