Frequent-relapsing, steroid-dependent minimal change disease: is rituximab the answer?

In patients with minimal change disease, development of steroid-dependency or frequent relapses pose difficult therapeutic problems. Prolonged administration of corticosteroids or the use of additional immunosuppressive therapy can result in significant toxicity. Recent data point to the use of rituximab as an important treatment option to induce long-term remission in patients with minimal change diseases who are either frequent relapsers or require significant immunosuppression to remain in remission. Minimal change disease (MCD) accounts for the majority of cases of idiopathic nephrotic syndrome (NS) in children and up to 20% of cases of idiopathic NS in white adults [1]. On kidney biopsy, MCD is characterized by widespread effacement of epithelial cell foot processes on electron microscopy, while glomeruli appear normal on light microscopy and immunoglobulin and complement deposition are absent on immunofluorescence. Most cases of MCD are idiopathic, although drugs (such as non-steroidal anti-inflammatory drugs), hematological malignancies (mainly Hodgkin lymphoma) and thymoma are well-recognized causes of secondary MCD. While most patients respond to corticosteroid therapy, up to 25% of treated patients have frequent relapses and up to 30% of patients become steroid dependent [2, 3]. In these patients, alternative therapies aimed at minimizing corticosteroid toxicity have been used, including alkylating agents, antimetabolites and calcineurin inhibitors. While these agents may be beneficial, some patients respond poorly or not all, and their use may be complicated by the development of serious adverse effects, e.g., infertility and malignancy with the use of cyclophosphamide. With calcineurin inhibitors, steroid de