 IgA nephropathy occurs when IgAa protein that helps the body fight infectionssettles in the kidneys. IgA deposits may cause the kidneys to leak blood and sometimes protein in the urine. Proteinuria abnormal amounts of protein in urine can be a sign of kidney damage. Current treatments for IgA nephropathy is limited to Angiotensin Converting Enzyme ACE inhibitor medications with fish oil. ACE Inhibitors, also called ACEI medications, slows the angiotensin converting enzyme so that blood vessels can be relaxed. 