What causes low immunoglobulin G?

Low immunoglobulin G (IgG) levels can be caused by various factors, including genetic conditions such as common variable immunodeficiency (CVID) or X-linked agammaglobulinemia. Chronic infections, certain autoimmune diseases, and treatments like chemotherapy or immunosuppressive therapy can also lead to decreased IgG production. Additionally, malnutrition or conditions affecting the bone marrow may impair antibody synthesis. It is important for individuals with low IgG to consult a healthcare professional for proper diagnosis and management.