Steroid and cyclophosphamide in IgA nephropathy.

BACKGROUND: IgA nephropathy is associated with a wide spectrum of possible lesions. Therefore, different responses to anti-inflammatory or immunosuppressive therapies should be expected with acute inflammatory changes, which are predominantly reversible, and with prevalently sclerotic lesions.

METHODS: The effects of a combined schedule of prednisone and cyclophosphamide was analysed in the specific subset of IgA nephropathy patients with acute inflammatory histologic changes associated with haematuria and proteinuria. Two groups of patients, with similar histologic lesions and clinical presentation, were considered. The first group (12 patients) was treated within 1 week after renal biopsy; starting with three pulses of methylprednisolone (1 g) followed by oral prednisone (0.8 mg/kg body weight for 2 weeks, 0.6 mg/kg for another 2 weeks, 0.4 mg/kg for an additional 4 weeks, then slowly tapered by 5 mg each month until discontinuation) and 1.5 mg/kg cyclophosphamide for 2 months. A second sample of eight untreated patients served as a control group. Treated and untreated patients had diffuse mesangial proliferation with florid crescents (8-60% in treated and 10-40% in untreated patients) with mild degree of glomerular sclerosis and interstitial changes. Basal creatinine (167 micromol/l, range 79-371 vs 132 micromol/l, range 79-256) and proteinuria (3.0 g/24 h, 1.0-4.9 vs 3.3 g/24 h, 1.0-13.7) were not statistically different between treated and untreated patients respectively. Nine treated and six untreated patients were hypertensive. Blood pressure treatment did not include ACE-inhibitors.

RESULTS: Untreated patients' 5-year renal survival, as assessed by the Kaplan-Meier method, was found to be significantly lower than treated patients (37.5 vs 91.6%, log-rank P=0.01 and Breslow test P=0.008; relative risk to reach the endpoint of a 100% increase in serum creatinine=3.58, P=0.03).

CONCLUSION: This short course of therapy with prednisone and cyclophosphamide has been effective in a subset of IgA nephropathy patients with florid glomerular changes and major urinary abnormalities, turning off phlogistic activity and preventing subsequent progression toward renal failure.