The most common group of Primary Immunodeficiencies are primary antibody deficiencies.¹ These syndromes are characterized by an inability to produce clinically effective immunoglobulin responses. Therefore the final common consequence is an inability to produce effective humoral immunity against invading pathogens. They can present at any age and the spectrum of deficiency can be broad, ranging from patients with a severe reduction of all serum immunoglobulin classes and totally absent B cells, to patients who have a selective antibody deficiency with normal serum immunoglobulin.

Hypogammaglobulinemia is the major hallmark of patients with a primary antibody deficiency and the main manifestation is recurrent bacterial infections, predominantly occurring in the respiratory and gastrointestinal tracts.

Patients at any age with recurrent infections (especially in the upper and lower respiratory tracts), those with infections in more than one anatomical site and those in whom the frequency or severity of infection is unusual should be investigated for antibody deficiency.

Primary Antibody Deficiency products include:

• Immunoglobulins and subclasses
• Vaccine response