Renal Disease in Lupus

Renal involvement, ranging from a small amount of proteinuria to acute glomerulonephritis and renal failure, affects up to 50% of lupus sufferers. All patients need screening for renal involvement with regular checks of serum creatinine and urine dipstick for protein and blood. The prognosis of patients with lupus nephritis has improved with advances in treatment.

There has been considerable debate concerning the value of renal biopsy in patients with lupus nephritis. Indications for biopsy include worsening renal function, proteinuria greater than 1gm per day and/or active urinary sediment, especially the presence of cellular casts. On the basis of renal biopsy information, lupus nephritis can be categorised according to major classification schemes (the WHO classification).

Although debated, several risk factors for progressive renal impairment have been identified. These include elevated creatinine at presentation, combined score on activity and chronic damage, delay between onset of renal disease and biopsy, black-race, and poor socio-economic groups.

The exact treatment of lupus nephritis depends on the severity of the renal lesion. However, in all patients, control of hypertension is imperative. For more active lesions, immunosuppressive therapy involves a combination of prednisolone and either azathioprine or cyclophosphamide.

Other agents that are available to treat lupus nephritis include cyclosporin A and mycophenolate mofetil. There is considerable interest in monoclonal antibodies, particularly anti-CD 40 Ligand. The evidence from animal models suggests that this may be a useful agent.

For those that fail immunosuppression and develop end-stage renal failure, renal transplantation has been performed successfully.