Recovery from rituximab-associated persistent hypogammaglobulinaemia in children with nephrotic syndrome.

Background and Hypothesis: There are limited data on the long-term outcomes and risk factors for non-recovery after development of rituximab (RTX)-associated persistent hypogammaglobulinaemia among children with idiopathic nephrotic syndrome (NS).
Methods: A nationwide Japanese survey was conducted to determine the prognosis of patients with childhood-onset idiopathic NS who developed persistent hypogammaglobulinaemia after RTX administration. Specifically, predictors of IgG level recovery and risk factors for serious infection were examined.
Results: The cohort comprised 118 patients (66.1% boys; median age at initial RTX administration, 7.5 years). Among the 121 patients diagnosed with persistent hypogammaglobulinaemia, only 31 (26.3%) recovered within a median observation period of 2.8 years; approximately 70% of patients continued to exhibit persistent hypogammaglobulinaemia. Among the patients who recovered from hypogammaglobulinaemia, the median time to recovery was 14.1 months. Patients with a history of steroid-resistant NS were less likely to recover from persistent hypogammaglobulinaemia (hazard ratio, 0.28; 95% CI, 0.09-0.87). In addition, of the 118 eligible patients, 18 (15.3%) developed serious infections requiring hospitalization, and the main risk factor for infection during hypogammaglobulinaemia was agranulocytosis (a well-known adverse effect of RTX in children).
Conclusions: A significant portion of patients with RTX-associated persistent hypogammaglobulinaemia did not exhibit recovery even after 1 year. Moreover, the data indicate that patients with a history of steroid-resistant NS have a significantly lower probability of recovering from this condition. Agranulocytosis under hypogammaglobulinaemia was significantly associated with an elevated risk of serious infections.
(© The Author(s) 2024. Published by Oxford University Press on behalf of the ERA.)