[Vaccine recommendations for children with idiopathic nephrotic syndrome]

The specific treatment of idiopathic nephrotic syndrome is based on corticosteroid therapy and/or steroid-sparing immunosuppressive agents in children who are steroid-dependant or frequent relapsers (60-70 %). Patients have an increased infectious risk not only related to the disease during relapses (hypogammaglobulinemia and urinary leakage of opsonins) but also to treatments (corticosteroids or immunosuppressive agents) in period of remission. Vaccination is therefore particularly recommended in these patients. Potential vaccine risks are ineffectiveness, induction of vaccine disease and relapse of idiopathic nephrotic syndrome. Only live vaccines expose to the risk of vaccine disease: they are in general contra-indicated under immunosuppressive treatment. The immunogenicity of inactivated vaccines is reduced but persists. The immunogenic stimulus of vaccination may in theory trigger a relapse of the nephrotic syndrome. Nevertheless, this risk is low in the literature, and even absent in some studies. The benefit-risk ratio is therefore in favor of vaccination with respect to the vaccination schedule for inactivated vaccines, with wide vaccination against pneumococcus and influenza annually. Depending on the context and after expert advice, immunization with live vaccines could be discussed if residual doses/levels of immunosuppressive treatments are moderate and immunity preserved.