Low IgG is not a disease in itself but a laboratory finding with two broad categories of causes:
Low Immunoglobulin G represents a critical breach in the body’s humoral defenses. While primary genetic causes are rare, secondary deficiencies due to modern immunosuppressive therapies and hematologic malignancies are increasingly prevalent. The clinical spectrum—from transient infantile deficiency to life-threatening CVID—requires a high index of suspicion from clinicians. With accurate diagnosis, particularly the distinction between numerical deficiency and functional failure, effective therapies ranging from antibiotic prophylaxis to lifesaving immunoglobulin replacement are available. As the use of B-cell-depleting therapies expands, understanding hypogammaglobulinemia will remain an essential competency for physicians across disciplines, ensuring that the "silent" loss of IgG does not lead to devastating infectious consequences. inmunoglobulina g baja
Introduction