Inmunoglobulina G Baja ((top)) -

Introduction

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

Low IgG is not a disease in itself but a laboratory finding with two broad categories of causes: Low total IgG must be confirmed with a repeat test

begins with a quantitative serum immunoglobulin panel (IgG, IgA, IgM). Low total IgG must be confirmed with a repeat test. Crucially, a low number alone is insufficient; the functional response must be assessed via specific antibody response to vaccines (e.g., tetanus or pneumococcal polysaccharide vaccine). A failure to mount a protective antibody titer confirms a clinically significant deficiency. the clinical consequences for affected patients

Immunoglobulin G (IgG) is the most abundant antibody isotype in human serum, constituting approximately 75-80% of all immunoglobulins. It serves as a cornerstone of the adaptive immune system, providing long-term defense against bacterial and viral pathogens. A low level of IgG, a condition known as hypogammaglobulinemia, represents a significant failure of humoral immunity. This essay explores the critical functions of IgG, the primary etiologies leading to its deficiency, the clinical consequences for affected patients, and the modern strategies for diagnosis and management.