Urinary epidermal growth factor predicts complete remission of proteinuria in Chinese children with IgA nephropathy.

"Competing interests The authors declare no competing interests."

"Funding This research was funded by the Beijing Natural Science Foundation (Z190023), the Capital Characteristic Clinical Application Research supported by Beijing Municipal Science & Technology Commission (Z181100001718134), Peking University Medicine Seed Fund for Interdisciplinary Research supported by “the Fundamental Research Funds for the Central Universities” (BMU2018MI015), and Beijing key laboratory of molecular diagnosis and study on pediatric genetic diseases (BZ0317)."

"The patients were selected from the Registry of IgA Nephropathy in Chinese Children (RACC, registration no. in clinicaltrials.gov: NCT03015974). RACC cohort prospectively enrolled children with IgAN from 28 centers across China. Clinical data, pathological classification, medications prescribed, and urine samples were prospectively collected from participants after enrollment into the RACC study and during follow-up. In this study, patients were selected according to the following inclusion criteria: (1) age <18 years; (2) biopsy-proven IgAN; (3) urine supernatant samples available; and (4) 24-h urinary protein (24-h UP) >150 mg/d and urine protein: creatinine ratio >0.2 g/g at baseline. Patients were excluded when their IgA deposition in glomeruli was suspected to be secondary to the other diseases. The baseline in this study was defined as the date of the first urine sample collection for each patient."