The effectiveness of pulse-dose intravenous steroid treatment was studied in acute phase of lupus nephritis with renal failure rapidly progressive despite conventional therapy. On 5-6 consecutive days 1g of prednisolone or methylprednisolone was given intravenously to 33 patients with a mean initial serum creatinine 5.9 +/- 4.1 mg/dl (521.6 +/- 362.4 mumol/l); then the patients were placed on conventional therapy. Immediate remission (group I), lasting at least 6 months, was achieved in 23 patients (69.7%), with a significant decrease of serum creatinine from 4.5 +/- 3.2 mg/dl (397.8 +/- 282.9 mumol/l) to 1.3 +/- 0.7 mg/dl (114.9 +/- 61.9 mumol/l) (p < 0.001) within 3 months. In 19 patients the remission lasted more than a year; till now the longest one is 13 years. In 10 patients (group II), the therapy brought no improvement and they went quickly into terminal renal failure. In this group the initial serum creatinine was 8.9 +/- 3.6 mg/dl (786.8 +/- 318.2 mumol/l), which was much higher than in the I group. All those patients were admitted to chronic dialysis programme; however, 5 of them died during the first 3 months of the treatment. The most frequent complications of the therapy were infections; all but one (a generalized zoster being a cause of death) caused no therapeutic difficulties. Pulse-dose intravenous steroid treatment makes achieving rapid clinical remission possible even in cases of advanced renal failure due to acute phase of lupus nephritis, refractory to conventional therapy.