Key clinical point: Gene variants associated with inborn errors of immunity were highly prevalent among patients with rheumatic diseases who developed persistent secondary hypogammaglobulinemia after starting on immunomodulatory therapy.

Major finding: Among 64 patients with persistent secondary hypogammaglobulinemia, 48% had such variants.

Study details: Single-center cohort study of patients with autoimmune rheumatic diseases.

Disclosures: Study funders included the German Research Foundation, the German multiorgan Autoimmunity Network, Hannover Medical School, the Rose-marie-Germscheid Foundation, the German Academic Exchange Service, HBRS, the Center for Infection Biology, and the German Center for Infection Research. The investigators reported having no competing interests.