Systemic lupus erythematosus (lupus glomerulonephritis)
Systemic lupus erythematosus disease is much more common in females than in males and in black rather than white individuals. All varieties of histological abnormality are seen, ranging from a minimal-change lesion to crescentic glomerulonephritis. The World Health Organization classification of histological types is:
- Type I - Normal on light microscopy
- Type II - Mesangial change, whether seen on light microscopy or detectable only by immunological staining and/or electron microscopy
- Type III - Focal proliferative
- Type IV - Diffuse proliferative
- Type V - Membranous.
Serial renal biopsies show that in approximately 25% of patients, histological appearances alter from one histological classification to another during the interbiopsy interval. The prognosis is better in patients with Types I and V.
Pregnancy is associated with significant risk to the lupus patient, not only owing to hypertension and premature delivery, but also to more rapid progression of the glomerular lesion following delivery.
Whilst corticosteroid therapy improves the extrarenal manifestations of SLE, evidence is lacking that this treatment alters the renal prognosis. Both azathioprine and cyclophosphamide improve renal function, but long-term studies suggest that cyclophosphamide is better.
There is no proof that intravenous 'pulse' cyclophosphamide treatment is safer or more efficacious than continuous oral therapy. Mycophenolate mofetil with prednisolone has recently been shown to be effective.
The indications for treatment vary. Those whose urine sediment contains many red cells and red-cell casts and those in whom renal function is impaired or is observed to deteriorate are strong candidates for treatment.
A histological diagnosis should be obtained before commencing such potentially hazardous treatment.
|