IgA nephropathy and Henoch Schönlein nephritis, pediatric

Immunoglobulin A (IgA) nephropathy is the most common form of glomerulonephritis worldwide and an important cause of chronic kidney disease in both children and adults. It is characterized by mesangial deposition of IgA that is seen on immunofluorescence of a kidney biopsy. The initial step in pathogenesis seems to be the aberrant glycosylation of IgA molecules. Proximate step/s to this aberrant glycosylation are still under investigation. While the clinical features can be variable, recurrent episodes of macroscopic or gross hematuria are the hallmark of pediatric IgA nephropathy. Currently, there is not one accepted treatment for IgA nephropathy, and most of the proposed regimens are lacking definitive evidence. The mainstay of therapy involves supportive measures that aim at slowing the progression of IgA nephropathy. Henoch-Schönlein purpura (HSP) or IgA vasculitis has been described as a small vessel, leukocytoclastic vasculitis that affects the skin, gastrointestinal tract, joints, and kidney. While HSP is the most common form of vasculitis in children, nephritis occurs in only about 20-50% of all cases. As compared to IgA nephropathy, renal biopsy findings in HSP nephritis are often severe, showing acute glomerular inflammation. Currently, physicians rely on clinical case series and experience in the management of HSP nephritis. There is a need for large, well-designed clinical studies to determine the best regimens for the treatment of HSP nephritis in children.