[Effects of methylprednisolone pulse therapy in the insidious type of crescentic glomerulonephritis]

In a attempt to clarify the effects of methylprednisolone pulse therapy on the insidious (subacute) type of crescentic glomerulonephritis with slow, but steady deterioration of renal function and poor response to treatment, we analyzed the clinical course of 24 patients (male:female = 15:9) with a mean age of 48.5 years. They fulfilled the following criteria: 1) crescents were observed in more than 50% of the glomeruli, 2) the increment of serum creatinine (Cr) could be determined sequentially on three or more occasions before treatment, and reciprocals of serum Cr declined with slopes of less than 1.0 x 10(-2) dl/mg/day, 3) corticosteroids and/or immunosuppressants were administered. The patients were divided into two groups: pulse therapy group (P) (15 patients), to which methylprednisolone 500 or 1,000 mg a day was administered intravenously for three consecutive days, and a conventional therapy group (C) (9 patients). There were no differences between groups P and C in clinical parameters, including sex, age, underlying diseases, urinary protein, blood pressure, serum Cr and slope of 1/Cr before treatment, and pathological findings, including percentages of glomeruli with crescents and degree of interstitial lesions. However, improvement of serum Cr, which was defined as a decline to the normal range or less than half of the pretreatment level, was observed in 9 (60%) in group P vs. only 1 (11%) in group C (p < 0.05). Re-biopsies were performed after treatment in 6 patients of group P with an improvement of serum Cr, and showed a decrease in the rate of crescent formation and almost complete loss of cellular crescents. At 1, 2 and 3 years follow-up, the renal survival rates were 86, 70 and 53%, respectively, in group P vs. 67, 14 and 14% respectively, in group C (p < 0.05). No serious side effects were observed in group P. These results suggest that methylprednisolone pulse therapy may be very effective for the insidious type of crescentic glomerulonephritis.