By Paul Der Mesropian, M.D. Nephrologist

How often does lupus involve the kidneys?

Lupus is an autoimmune, systemic disease that can affect several organs. It affects the kidneys about half the time. Kidney disease is more likely if lupus is active (i.e., there are active inflammatory symptoms or certain blood tests indicating disease activity). However, even patients whose lupus is controlled with medications such as Plaquenil (hydroxychloroquine), are at risk for developing a lupus flare involving the kidneys. It is important to periodically monitor for “lupus nephritis”.

What findings may signal lupus nephritis?

Typically, people with lupus nephritis have abnormal laboratory testing about the kidneys. Symptoms related to kidney dysfunction are usually present but are more likely to appear when the kidney disease is more advanced.

What are some of the symptoms associated with kidney disease?

• Foamy or dark/ bloody urine
• Decrease in urination
• Fatigue or malaise
• Swelling (in the legs, arms, or face)
• Weight gain
• Increase in blood pressure (above 130/80)

What laboratory tests detect lupus nephritis?

Kidneys clean the blood of waste products. They do this by filtering the blood through millions of small filtration units (about 1 million in each kidney), resulting in the production of urine. Normally, when this process occurs, blood or proteins found within it should not enter (or “leak”) into the urine. However, if there is inflammation of the small filters which make up the kidneys, blood or an abnormal amount of protein can leak in the urine.  Inflammation can also impair kidney function (i.e., the cleaning ability of the kidneys as measured on bloodwork). For this reason, it’s important to regularly perform a urinalysis to check for blood or protein, and routinely monitor kidney function with a blood test called creatinine (a value of generally 1 mg/dl or below is considered normal in adults).

At what intervals should kidney tests be monitored?

Scenario #1

If there is no previous history of lupus nephritis, a urinalysis and creatinine in the blood should be checked at least semi-annually (every 6 months).

Scenario #2

If there is a history of lupus nephritis, quarterly lab monitoring (every 3 months).

Scenario #3

If there is active lupus nephritis, frequent lab monitoring, at least monthly, is recommended during treatment.

When should a kidney specialist be seen?

Patients with evidence of active lupus nephritis, characterized by blood or significant protein leaking into urine and/or reduced kidney function, should see a kidney doctor. Almost always, a kidney biopsy would be necessary to confirm the diagnosis, determine how advanced the process is, and direct the treatment plan.

A kidney biopsy is a procedure in which a small sample of kidney tissue is taken with a needle and then examined under the microscope by a pathologist to obtain the most accurate diagnosis possible.

What are the treatment options for lupus nephritis?

Specific treatment usually involves powerful immunosuppressive medications —either Cytoxan (cyclophosphamide) or CellCept (mycophenolate mofetil) in combination with steroids—to calm down the inflammation and hopefully improve kidney function.

Nonspecific medications known as “ACE inhibitors” (such as lisinopril) or “angiotensin receptor blockers” (such as losartan) may also be used to reduce protein leaking into the urine, if present (these are also blood pressure-lowering medications).

Special attention to the medication regimen needs be paid in patients who are or want to get pregnant.

In the worst-case scenario, lupus nephritis can severely damage the kidneys to the point where therapy that replaces kidneys—namely, dialysis or kidney transplantation—becomes necessary.

Conclusion

If you live with lupus or someone dear to you does, and you want to get involved fighting “one of the world’s cruelest, most unpredictable, and devastating diseases, support your local Lupus Foundation of America chapter!

Medical Disclaimer

This information is offered to educate the general public. The information posted on this website does not replace professional medical advice, but for general information purposes only. There is no Doctor – Patient relationship established. We strongly advised you to speak with your medical professional if you have questions concerning your symptoms, diagnosis and treatment.