erger’s disease is also known as IgA nephropathy, or called idiopathic hematuria within the medical community.  It’s unlikely you’ve ever even heard of it, but one of the most common signs of it is blood in the urine.  This kidney disease occurs when the antibody immunoglobulin A abnormally deposits into the kidney, and subsequently damages the tiny filtering units within the kidney. The protein immunoglobulin A is abbreviated as IgA, as you will see here. By damaging these filtering units within the kidney, IgA hinders the kidney from doing one of its most important jobs – filtering waste, toxins, and excess water/electrolytes from the blood.