Kidney Manifestations of Rheumatological Diseases in Children

Paediatric rheumatological diseases are a group of multi-systemic inflammatory diseases affecting children and young people. The kidneys constitute a target organ during the acute presentation and life course of several multi-systemic inflammatory conditions including childhood systemic lupus erythematosus (cSLE), IgA vasculitis and ANCA-associated vasculitis. Unlike adults with rheumatic diseases, who may have prior concomitant kidney disease, children are more likely to have an acute, potentially reversible inflammatory process that typically requires prompt immunosuppressive treatment. Despite broad-spectrum immunosuppression, kidney outcomes remain suboptimal, with children progressing to irreversible chronic kidney disease and ultimately kidney failure, requiring kidney replacement therapy or transplantation. In cSLE, for example, the kidney failure rate is 1–14% depending on the length of follow-up, with the average age of requiring a kidney transplant reported to be 24 years, thus illustrating the importance of follow-up into adulthood. Advances in improving the outcomes for these patients remain slow, and the recruitment of children to drug trials can be challenging. The aim of this review article is to summarise the key paediatric rheumatic diseases that commonly involve the kidney to highlight the epidemiology and current kidney outcomes. Useful information is also provided on suggested screening to detect the presence of active kidney inflammation and improvements in this field for the future. © 2023, The Author(s).