Development of Common Variable Immunodeficiency in an 8-year-old Boy Treated with Rituximab for Idiopathic Thrombocytopenia

We present the case of an 8-year-old boy who developed common variable immunodeficiency (CVID) following rituximab therapy for the treatment of idiopathic thrombocytopenia (ITP). Since rituximab can cause prolonged hypogammaglobulinemia and increased susceptibility to infections, monitoring of immunoglobulin levels, antibody responses, B cells, and memory B cell subpopulations is recommended. This may be especially true when rituximab is used in the treatment of immune cytopenia such as ITP, which may occur in CVID.