A relationship between IgA nephropathy (IgAN) and the mucosa has long been recognized with evidence from clinical observations and genetic studies suggesting that abnormalities in the IgA mucosal immune system could be a key element in the pathogenesis of IgAN. In this Review, Jürgen Floege and John Feehally describe current evidence that links the mucosa, in particular the gastrointestinal mucosa, and IgA produced in the bone marrow with IgAN.
The mucosa–kidney axis in IgA nephropathy