Lupus Nephritis

What is Lupus Nephritis?
Statistics on Lupus Nephritis
Risk Factors for Lupus Nephritis
Progression of Lupus Nephritis
How is Lupus Nephritis Diagnosed?
Prognosis of Lupus Nephritis
How is Lupus Nephritis Treated?
Lupus Nephritis References
Drugs/Products Associated with Lupus Nephritis

What is Lupus Nephritis?

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Lupus nephritis is a disease affecting the kidneys. Systemic lupus erythematosus (SLE) is a systemic autoimmune disorder which causes significant renal disease, primarily affecting the glomerulus.

Statistics on Lupus Nephritis

SLE is rare, affecting 3-4 per 100,000 patients in the UK. The condition is nine times more common in females than males, and nine times more common in Asian and Afro-Caribbeans than Caucasian populations.

Renal disease is estimated to occur in 20-50% of patients with SLE.

Risk Factors for Lupus Nephritis

The only known predisposing factor is the presence of SLE, which has the sole predisposing factor of family history.

Progression of Lupus Nephritis

The natural history of this condition is not yet fully understood. Early in the disease process, the condition is usually silent with only one-half experiencing clinical symptoms. It is generally held that mild forms of lupus nephritis will progress to more severe and symptomatic forms in about 5% of patients. With progression of the nephritis, the tubules of the kidney may also become involved and renal failure may ensue. In a minority of cases, tubular involvement tends to be the predominant feature.

Only 20% of patients will have lupus nephritis at the time of diagnosis. Over the next 10 years, the rate of renal involvement steadily increases. After ten years, the onset of new renal disease from lupus nephritis is greatly reduced.

In rare cases, lupus nephritis may be the only consequence of SLE.

How is Lupus Nephritis Diagnosed?

General investigation of SLE will require a number of blood tests to be completed. There are specific markers present in the blood which idenifty SLE disease.

Prognosis of Lupus Nephritis

The prognosis of this condition is strongly associated with the appearance of the kidney beneath the microscope. The mild forms of disease are associated with a good prognosis, with most mainatining good kidney function. When more severe forms are present, the patient will be more likely to develop renal failure and will therefore carry a poorer prognosis.

How is Lupus Nephritis Treated?

There are two phases of treatment, which reflect the two stages of disease.

Induction phase

Initial treatment is guided by the results of blood and biopsy tests. The main drugs used are steroids, which are commonly used alone for lesser forms of the disease. These are combined with more potent drugs (with more side-effects but better action) when more severe types of lupus nephritis are identified.

Maintenance therapy

Patient are required to take anti-inflammatory drugs over a long period time (greater than 10 years) in order to prevent recurrence of their lupus nephritis. Steroids are the mainstay again for maintenance therapy. Most patients cease therapy after five years, as instructed by their doctor who is guided by regular urine and blood testing.

Lupus Nephritis References

Braunwald, Fauci, Kasper, Hauser, Longo, Jameson. Harrison's Principles of Internal Medicine. 15th Edition. McGraw-Hill. 2001.
Cotran, Kumar, Collins 6th edition. Robbins Pathologic Basis of Disease. WB Saunders Company. 1999.
Longmore M, Wilkinson I, Torok E. Oxford Handbook of Clinical Medicine. Oxford University Press. 2001.