A reader left a comment and question yesterday about kidney disease and Sjogren's Syndrome. It was a very good question and deserved a more thorough answer than my brief reply.
Her question was:
I came to this blog because of Sjogren's. I have been diagnosed with it for almost 4 years now. It has affected my kidneys to the point that I have stage IV chronic Kidney Disease. I am scared that I will be put on dialysis in the next couple of years. I am being put on Procrit injections. Have you had to do this or know someone that Sjogrens has affected their kidneys badly?
The impact that Sjogren's has on the entire body should never be underestimated. Too often, medical caregivers are unaware of the existence of this autoimmune disease. Many have only a sketchy understanding of Sjogren's, and assume that the disease affects simply the eyes and the saliva glands.
The reader's problems with her kidney function as a result of Sjogren's is unfortunately a good example of the possible systemic, meaning body-wide, complications of this disease. Other organs which may be affected include the lungs, liver, organs of the intestinal tract, the nervous system, the skin and connective tissues, and kidneys.
Kidney involvement as a result of Sjogren's Syndrome is not uncommon, but the percentage of patients with serious and obvious symptoms is small. The most common problem in kidney function occurs when lymphocytes, a specific white blood cell, mistakenly identify kidney tissue as foreign to the body. They then move in to the kidney in large numbers, and attack the kidney. Most frequently, these "broken" lymphocytes move into the tissue around specialized kidney filters, and cause a condition called interstitial nephritis, resulting in the patient passing large amounts of un-concentrated urine.
Another condition, renal tubular acidosis, occurs when these lymphocytes cause the kidneys to become unable to excrete a highly acid urine. This can result in an imbalance of normal salts and other essential blood chemicals.
Less commonly seen are problems which lead to progressive kidney failure.