Glucocorticoid therapy is the treatment of choice in minimal change disease (MCD), leading to a complete remission of proteinuria in over 85 to 90 percent of cases. This approach is based upon the beneficial results reported in several large prospective randomized trials in children, extensive observational studies in children and adults, and a very limited number of small randomized controlled trials in adults that compared prednisone with no specific therapy or that compared various prednisone regimens [1-6]. Due to their small size, the results of these controlled trials are not definitive.
MCD accounts for 90 percent of cases of the idiopathic nephrotic syndrome in young children (under age six years) and 65 percent of cases in older children [7-9]. As a result, glucocorticoid therapy is usually begun empirically in children, and a kidney biopsy is performed only for glucocorticoid-resistant disease. (See "Etiology, clinical manifestations, and diagnosis of nephrotic syndrome in children" and "Treatment of idiopathic nephrotic syndrome in children".)
In comparison, MCD accounts for only 10 to 25 percent of cases of nephrotic syndrome in adults [10-12]. Thus, patients over age 16 years are generally treated after kidney biopsy that shows MCD. (See "Etiology, clinical features, and diagnosis of minimal change disease in adults".)
Children tend to remit rapidly, with 50 percent responding within two weeks and almost all within eight weeks [7,13]. Adults tend to respond more slowly, with more than 25 percent of responders taking three to four months or longer to undergo complete remission (figure 1) [13-17]. Therefore, the definition of steroid resistance is not the same for patients younger than about 16 years of age and for those over about 17 years of age.
The treatment of MCD in adults will be reviewed here. The treatment of other frequent causes of the nephrotic syndrome occurring in adults, such as focal segmental glomerulosclerosis (FSGS), membranous nephropathy, and primary amyloidosis, are discussed separately. (See "Treatment of primary focal segmental glomerulosclerosis" and "Treatment of idiopathic membranous nephropathy" and "Prognosis and treatment of immunoglobulin light chain (AL) amyloidosis and light and heavy chain deposition diseases".)