Hypogammaglobulinemia

Etiologies

• Primary hypogammaglobulinemia
  • Common variable immunodeficiency (CVID)
  • IgG subclass deficiencies, including IgG1, IgG2
  • Hyper-IgM syndrome
  • ADA deficiency
  • Hypomorphic recombination-activating gene mutation
  • Artemis defect
• Secondary hypogammaglobulinemia
  • Decreased production
    • Medications, including B-cell depletion (rituximab, CAR-T, BiTE), corticosteroids, antiepileptic medications, and chemotherapy
    • Malignancy, including CLL, lymphoma, multiple myeloma, Waldenström macroglobulinemia, and thymoma (Good syndrome)
  • Increased loss: protein-losing enteropathy, nephrotic syndrome, burns, trauma