The application of omalizumab in children with atopic diseases complicated by nephrotic syndrome: a case report.

Nephrotic syndrome (NS) and atopic diseases are linked through shared immunological pathways, with allergic triggers often contributing to NS relapses, particularly in immunoglobulin E (IgE)-mediated pathways. Omalizumab, a humanized monoclonal antibody targeting free and cell-bound IgE, is commonly used in treating atopic diseases. We presented a pediatric case with a history of eczema, asthma, and recurrent atopic rhinitis, who first developed NS at age three, responding well to steroid therapy. The patient experienced four NS relapses, three of which were associated with significant atopic symptoms, elevated eosinophil counts, and increased IgE levels, suggesting allergic triggers. After the latest relapse achieved remission, steroid therapy was discontinued, and Omalizumab was initiated two months later. The patient received monthly subcutaneous Omalizumab (300 mg) with regular urine protein monitoring. To date, the patient has shown marked improvement in atopic symptoms, sustained NS control, and reduced steroid dependence. This case highlights the potential of Omalizumab in treating NS triggered by allergic reactions, further prospective pilot studies and randomized controlled trials are warranted to rigorously evaluate its efficacy and safety.