Lupus Symptoms Diagnosis Nephritis

Systemic lupus erythematosus (SLE) is an autoimmune disease in which autoantibodies are produced. These autoantibodies attack the body’s healthy cells and tissues causing inflammation and pain. When autoantibodies become lodged in kidney tissues the kidney can become inflamed and damaged. Up to fifty percent of patients with SLE experience this condition, called lupus nephritis.

Lupus Nephritis: Kidney Inflammation

“Nephritis” is the term used to describe inflammation of the kidney. As with all symptoms of lupus, kidney inflammation can exist apart from lupus. Kidney problems may be associated with urinary tract infections, a kidney stone, or may occur as a side effect of certain medications. Therefore, a diagnosis of lupus cannot be made based on the presence of kidney inflammation alone.

Lupus nephritis can exist without visible symptoms. Often no pain or swelling is noticed. Frequent urination at night might suggest the loss of protein in the body. If large amounts of protein are lost in the urine, the nephrotic syndrome may occur. This may lead to symptoms like edema (fluid retention and swelling) in the feet, ankles and legs. These are often the first noticeable signs of lupus nephritis. Blood in the urine, known as hematuria, may also be a sign of kidney damage.

Diagnosing Lupus Nephritis

Doctors may perform tests to evaluate the presence of lupus. A urine sample is obtained from the patient and examined to determine whether unusual cells are in the urine. The presence of proteins, red blood cells or white blood cells in the urine suggests the possibility of lupus nephritis and necessitates further testing.

Creatinine Measurement and Other Blood Studies

Blood tests may follow the urinalysis to measure the effectiveness of the kidneys. One of the primary blood studies is the serum creatinine study, which shows whether the kidneys are removing waste products adequately. Creatinine is a waste product made by the body as a result of regular metabolism. If the kidneys are not working properly they are unable to excrete creatinine and therefore blood levels of creatinine increase. Other blood studies may include:

  • blood urea nitrogen (BUN)
  • serum albumin
  • serum sodium
  • potassium
  • bicarbonate.

Measuring Immune Abnormalities

Two common blood tests to detect immune abnormalities are the serum complement test, measuring levels of proteins in the blood, and the antibodies to DNA test, which measuring antibodies that are present to a higher degree with lupus nephritis.

Sometimes a biopsy is necessary to confirm the diagnosis of lupus nephritis and determine the severity of kidney disease. A kidney biopsy is the removal of a small specimen of kidney tissue. The kidney tissue is examined under a microscope to assess the amount of inflammation or damage.

Medications in the Treatment of Lupus Nephritis

Lupus nephritis needs to be treated before the kidney becomes seriously damaged or if kidney failure is imminent. Some of the common types of medications are listed below.

  • diuretic medications to decrease swelling in the tissues
  • blood pressure medications to regulate and decrease blood pressure
  • blood thinning medications to thin the blood and prevent clots
  • corticosteroids to help control inflammation and swelling
  • cytotoxic medications to hinder the function of the immune system.

Resources

Beers, M.H.