Lupus nephritis (also known as glomerulonephritis) affects about
1/3 of SLE patients. There are few signs of lupus nephritis, but
swelling of the ankles & around the eyes, nosebleeds, foaming
of urine, increased urination at night, & protein in the urine
are all signs. Pain in the abdomen or back, & pain during urination
are not symptoms of kidney disease, but are most likely signs of
infection (urinary infections are common in lupus & can be successfully
treated with antibiotics). If there is protein in the urine
on one occasion, & not the next, a very mild form of lupus nephritis
is likely & no treatment is usually necessary. In patients where
protein is present in the urine on more than one occasion,
more tests are required.
Tests for kidney disease include -
Urinalysis: a sample of urine is tested for the presence of blood
cells & protein, which if present indicate the need for further
tests.
Blood tests: Two tests are used to see if the kidney is doing
its job properly by ridding the body of excess fluids & waste
products, these tests are the blood urea nitrogen (BUN), & the
serum creatinine. If protein is being lost in the urine, there may
be lower protein levels in the blood, this is measured by the serum
albumin. Serum sodium, & potassium tests are carried out to
test for any imbalances of salt & water in the blood.
24-hour urine collection: Patients who are suspected of having
kidney disease may have to collect their urine over a 24-hour period,
The kidneys; ability to filter waste products, & the total amount
of protein lost can then be measured.
Kidney biopsy: A kidney biopsy may be performed to confirm the
diagnosis, to determine if kidney tissue is inflamed or scarred,
& to evaluate treatment. The type of lupus nephritis present
can also be classified. A kidney biopsy means inserting a needle
into the back, to remove a small piece of kidney.
Many factors must be taken into consideration before treatment
can be decided upon. Kidney disease is treated with steroids and/or
cytotoxic drugs. High doses of steroids are usually given until
an improvement is seen, the steroid dose can then be slowly reduced.
Also, diuretic drugs are used to eliminate waste fluid, & drugs
are used to control high blood pressure. A change in diet is also
necessary. Kidney disease can be treated, but some patients with
advanced kidney disease may develop renal failure which necessitates
kidney dialysis. In these cases kidney transplantation can also
be considered.