Hypogammaglobulinemia and B cell repopulation after rituximab in childhood nephrotic syndrome.
Prolonged hypogammaglobulinemia affects nearly half of children after rituximab treatment.
Hypogammaglobulinemia and B cell repopulation after rituximab in childhood nephrotic syndrome.
Rituximab is increasingly used to treat childhood nephrotic syndrome, although its long-term effects are poorly understood.
Our study aims to evaluate the incidence and risk factors for hypogammaglobulinemia, hematological complications, B cell repopulation, and relapses after rituximab treatment.
We included children (1-18 years of age) with nephrotic syndrome who were enrolled in a prospective cohort study (Greater Toronto Area, Canada) and received rituximab from June 2018 to December 2023.
nearly half had low IgG lasting a year or more after rituximab
Younger age (odds ratio [OR] 1.13, 95% CI 1.01-1.29), European ethnicity (OR 6.37, 95% CI 1.74-30.83), lower pre-treatment IgG (OR 1.63, 95% CI 1.24-2.31) and longer maintenance immunosuppression duration (OR 1.27, 95% CI 1.03-1.61) were risk factors for prolonged hypogammaglobulinemia post-rituximab.
Post-rituximab, 16% of the children had anemia, 21% had neutropenia, and 3% had thrombocytopenia.
Twelve children (17%) developed documented infections.
All children experienced complete B cell depletion post-rituximab, with B cell repopulation at median 6.3 months.
Prolonged hypogammaglobulinemia occurs in half of children with nephrotic syndrome post-rituximab.
Younger age, European ethnicity, lower pre-treatment IgG, and longer maintenance immunosuppression use are associated with higher prolonged hypogammaglobulinemia risk.