5TH NATIONAL CONFERENCE OF PEDIATRIC RHEUMATOLOGY, KOLKATA, 29TH & 30TH SEPTEMBER 2007

Surjit Singh
Additional Professor of Pediatric Allergy and Immunology, Advanced Pediatric Centre
Post Graduate Institute of Medical Education and Research, Chandigarh

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Intravenous immunoglobulin (IVIG) is a powerful therapeutic tool in the hands of the clinician. It consists of pooled normal intact polyspecific IgG derived from the plasma of healthy individuals (ideally unremunerated) donors who have been subjected to strict screening procedures based on clinical history, physical examination and state-of-the-art laboratory testing. The safety of a given IVIG brand, in fact, primarily depends on these screening procedures. Each batch of IVIG represents a donor pool of at least 4000-8000 individuals such that the repertoire of antibodies is representative of the population at large. Most IVIG preparations contain more than 90% monomeric IgG with only small amounts of IgA and IgM. Ideally the IgG subclass (i.e. IgG1, IgG2, IgG3 and IgG4) distribution of IVIG should be the same as in normal plasma, but this is dependent on the manufacturing processes to which the plasma has been subjected. For instance, some IVIG preparations do not contain the IgG3 subclass.

IVIG as treatment of choice
IVIG is the treatment of choice for Kawasaki Disease, autoimmune demyelinating polyradiculoneuropathy (AIDP or LGB Syndrome) and idiopathic thrombocytopenic purpura. The dose that is commonly used for these conditions is 0.5-2 g / kg stat but the same dose can also be administered spread over 4-5 days.

IVIG as physiological replacement therapy
IVIG is used as physiological replacement therapy in various forms of hypogammaglobulinemia eg. Bruton's Disease and Common Variable Immunodeficiency. The recommended dose is 0.4 g / kg every 3-4 weeks.

Misc. uses
The use of IVIG can also be considered in selected cases of severe myasthenia gravis, autoimmune neutropenia, neonatal alloimmune and autoimmune thrombocytopenia, crises of systemic lupus erythematosus and juvenile dermatomyositis not responding to conventional steroid therapy. IVIG is also used in the management of "difficult" vasculitides.

IVIG for prevention and treatment of Sepsis
IVIG has been used for prophylaxis and treatment of neonatal sepsis in low birth weight babies but the results are equivocal. Use of IVIG for treatment of sepsis in older children is even more controversial.

Administration of IVIG
Administration of IVIG can be associated with several side-effects. The infusion must be started very slowly (initially a drop per minute) and the child monitored for allergic reactions, which may include fatal anaphylaxis. The infusion rate can be slowed, or even discontinued, if the child develops chills or rigors. Longterm risks include transfusion-acquired Hepatitis C Virus infection, amongst others.

5th National Conference of Pediatric Rheumatology - Conference Abstracts. Pediatric Oncall [serial online] 2007 [cited 15 December 2007(Supplement 12)];4. Available from:
http://www.pediatriconcall.com/fordoctor/Conference_abstracts/ncpr/
intravenous_immunoglobulins.asp