Rheumatoid arthritis is an autoimmune disorder and can cause systemic vasculitis. If left untreated, it can cause kidney damage. So, how does rheumatoid arthritis cause kidney damage?
Immune system is a powerful protective system in human body.When foreign harmful substances known as antigens invade into your body, it can produce antibodies to recognize them and defeat them immediately. However, in some cases, there are autoantigens existing in your body due to some causes. When the foreign harmful substances invade into body, it can stimulate the production of autoantibodies. In normal condition, the level of autoantibodies keeps at a certain degree. If its level is too high, the antibodies will attack the healthy cells and tissues in body mistakenly. Or the antibodies encounter antigens in blood and form immune complexes. Then the complexes and autoantibodies may deposit in different parts of body, particularly in joints. If your kidneys are involved, it will cause damage to your kidneys.
When the immune complexes and autoantibodies deposit in the tiny blood vessels in kidneys, they will attract inflammatory factors to remove them from kidneys. Then, it can cause damage to the tiny blood vessels in kidneys. As the tiny blood vessels are the filtering units in kidneys, when they are damaged, a lot of proteins and red blood cells will pass through them and end up in urine.
Generally, immunosuppressive drugs and anti-inflammatory medications are used to treat kidney damage in rheumatoid arthritis. Actually, they have obvious effects in relieving symptoms like proteinuria, hematuria. However, if the immune complexes still exist in kidneys, the inflammation is very likely to relapse when there is some trigging factors.
Therefore, to control kidney disease in rheumatoid arthritis and prevent further kidney damage, they key is to eliminate the immune complexes and autoantibodies completely and regulate the autoimmune dysregulation. In this way, it can prevent the production of immune complexes and excessive autoantibodies. As a result, the damage to kidneys will be suppressed completely.