Description

• A disorder of the humoral immune system characterized by deficient or absent immunoglobulins and the inability to produce specific antibody
• Subtypes include primary immunodeficiency and secondary deficiency due to other extrinsic disease (i.e., malignancy).

Epidemiology

Incidence and prevalence depends on underlying defect or cause. Antibody deficiency syndromes represent ~70% of primary immune deficiencies.

Risk Factors

Genetic defects have been identified in many cases (see “Differential Diagnosis”).