Systemic Lupus Erythematosus (SLE)
Lupus Erythematosus (LE) is a disorder that may involve only the skin (cutaneous LE), or it may involve many parts of the body, including the kidneys (systemic LE, also known as SLE).
SLE affects people of all ages. Females are affected more often than males. Young women represent a large group of SLE sufferers. The cause of SLE is not clearly understood. An abnormal immune system from genetic and/or environmental factors may be responsible.
Kidney involvement is significant in SLE, but not all patients suffer from it. The extent to which the kidneys are affected by SLE is variable and involvement may also change over time. Kidney involvement is not always serious. Only one in five cases is severe.
SLE symptoms and signs of kidney involvement
There are many different symptoms of SLE. Common ones include joint pain and swelling, skin rashes, fever, and also signs of kidney involvement.
Kidney involvement may be detected with urine testing, e.g. protein in the urine. On other occasions, it may be discovered because of swelling or high blood pressure. Sometimes, it may present itself in abnormal blood tests during follow-up.
Symptoms of kidney failure occur in the later stages of kidney damage. Unfortunately, the degree of kidney disease may be more advanced than is apparent from the other signs of SLE.
Available treatments for SLE kidney disease
Treatment depends on the degree of damage. Your doctor may need to determine this with tests including urine, blood, or even with a kidney biopsy. In mild cases, treatment may be the same as for those patients with SLE who do not have kidney disease. However, in more severe cases, treatment with drugs like Prednisone, Azathioprine, or Cyclophosphamide may be required.
If blood pressure becomes high, then medication for high blood pressure is important.
If the kidneys fail, then dialysis or a kidney transplant are treatments that are available. A transplanted kidney is seldom affected by SLE.
With treatment, the outlook for SLE patients with kidney problems improves over the years. Even serious cases may improve, become stable, or be cured, although monitoring must continue to detect flare-ups of the disease.
Pregnancy and SLE kidney disease
Pregnancy is an important question for young women with SLE kidney disease. Before pregnancy is considered, you should consult your doctor. Your doctor will discuss with you the risks involved, taking into account the degree and severity of the kidney problem, blood pressure, prior pregnancy problems and SLE activity. Drugs may have to be taken during pregnancy and most are usually well tolerated.
With acknowledgement to C.K. Yeung, MD, FRACP, FRCPC, Nephrologist, Vancouver Hospital and Health Sciences Centre, Vancouver, B.C. for his assistance in compiling this information.