Idiopathic nephrotic syndrome is the most frequent
glomerular disease that presents during childhood and is mainly due to
minimal change nephropathy (MCNS) and focal-segmental
glomerulosclerosis (
FSGS). Its treatment is still challenging, with up to 50% of the patients who are initially
steroid sensitive (usually MCNS) being frequent relapsers and requiring additional long-term
immunosuppression. However, current
immunosuppressive regimens are associated with severe
toxicity. Only half of the steroid-resistant patients (usually
FSGS) achieve long-term remission even with intensive
immunosuppression and
plasma exchange.
Rituximab (RTX), a chimeric
monoclonal antibody inhibiting CD20-mediated
B-cell proliferation and differentiation, has recently gained attention as a potentially successful therapy for complicated
idiopathic nephrotic syndrome in children. A number of case reports and one prospective non-controlled
multicenter trial point to the beneficial effects of RTX as a rescue therapy in children with
steroid/cyclosporine-dependent or -resistant
nephrotic syndrome. However, publication bias often results in positive outcomes being more likely to be reported than negative ones and, in particular, the safety profile of this
drug in this group of patients remains unclear. Therefore, controlled
randomized studies are required to assess this issue, to develop treatment guidelines, to evaluate the therapeutic and economical efficacy, and to define criteria for the
selection of patients.
