Evaluation of proximal tubule functions at the children with COVID-19 infections: a prospective analytical study

Abstract Purpose: There are limited numbers of studies focusing on renal effects of COVID-19 infection and proximal tubular dysfunction in children with COVID-19 infections. In this study, we aimed to evaluate the functions of the proximal tubule in hospitalized children with confirmed acute COVID-19. Methods: This prospective descriptive study included the children who were hospitalized for confirmed COVID-19 were included. The diagnosis of proximal tubule injury was based on the presence of at least two of the following four abnormalities including abnormal tubular reabsorption of phosphate, normoglycemic glycosuria, hyperuricosuria, and proteinuria. Results: A total of 115 patients were included in the study. Approximately one-third of the patients had higher serum creatinine levels or proteinuria. Additionally, abnormal renal tubular phosphate loss measured by TMP/eGFR was present in 10 patients (8.7%) and hyperuricosuria was present in 28.6%. Consequently, overall PTD was present in 24 patients (20.8%), and PTD associated with COVID-19 was significantly detected in younger children.Conclusions: Our findings suggested that one in five children with acute COVID-19 infections had proximal tubular dysfunction. The rate of proximal tubular dysfunctions was not so high as in adults but should be kept in mind. The children with COVID-19 infections should be monitored for recovery of proximal tubular functions.