Estimation of the number of histological diagnosis for IgG4-related kidney disease referred to the data obtained from the Japan Renal Biopsy Registry (J-RBR) questionnaire and cases reported in the Japanese Society of Nephrology Meetings

Background More than 2 years have passed since the proposal of the diagnostic criteria for IgG4-related kidney disease (IgG4-RKD). The aim of this study was to estimate the number of histological diagnosis for IgG4-RKD throughout Japan and to clarify the regional distribution of the development of this disease.