Efficacy of Intravenous Immunoglobulin Replacement Therapy in Patients with Predominantly Antibody Deficiency

Background Intravenous immunoglobulin G (IVIG) has been used as an antibody replacement therapy in primary immunodeficiency (PID) for more than 50 years. Most routinely, IVIG is used in patients with predominantly antibody deficiency such as: X-linked Agammaglobulinemia, common variable immunodeficiency and combined immunodeficiency such as: severe combined immunodeficiency. Aim To evaluate the efficacy and safety of regular IVIG therapy among patients with predominantly antibody deficiency in terms of frequency of infection and adverse effects. Methods Thirty patients diagnosed with predominantly antibody deficiency were recruited from the Pediatric Allergy and Immunology Unit, Children’s Hospital, Ain Shams University. These patients were followed up for one year in order to evaluate the frequency of infection and and adverse reactions of regular monthly IVIG therapy. The adequacy of IVIG dose was evaluated by the trough level of serum immunoglobulin G (IgG). Results Of the 30 patients, 21 (70%) were males and 9 (30%) were females. They had a median age of 87 months (range:15-294). Their median age at presentation and at diagnosis were 36 months (range :3-168) and 87 months (range:15-204) respectively. The mean ± SD of serum IgG before commencement of IVIG and after were 265.10 ± 108.39mg/dl and 572.04 ± 186.72 respectively. The rate of major infection dropped after starting replacement therapy with a median of 2 (1-2) before and 0 (0-1) after treatment. In spite of the reduction in the rate of pneumonia occurrence in patients with IgG trough level >500 mg/dl, it had no statistical significance. This could be attributable to small sample size. One patient developed anaphylaxis and was shifted to another brand. Conclusion IVIG is a safe and effective drug for patients with predominantly antibody deficiency. Compliance, adherence to therapy and appropriate dosage is needed to achieve better infection control.