Do not administer immunoglobulins (IGs) for low IgA levels

Author: Esther Forrester, MD

What to Do - Interpret the Data

IgA deficiency is the most common primary immunodeficiency, with an occurrence ranging from 1/400 to 2,000 individuals. The frequency of IgA deficiency is greater in people of European descent and may be as high as 1 in 500. In the United States, whites are affected more than blacks by a ratio of 20:1. Asian Americans have an even lower incidence, with the occurrence in Japanese descendents being 1 in 18,500 persons.

IgA deficiency may be primary or secondary (acquired), sporadic, or familial. Both serum and secretory IgA are lacking in most patients and, rarely, one or the other is lacking. Inheritance is either autosomal recessive or dominant. The primary defect in selective IgA deficiency is related to a failure of B cells to differentiate in response to appropriate stimuli to mature isotype-switched surface IgA-positive B cells and IgA-secreting plasma cells.Thebasisfor thedefectis notknown. Certaindrugs,such asphenytoin, D-penicillamine, sulfasalazine, and hydroxychloroquine, have been associated with this entity. Congenital cases of noninherited IgA deficiency in association with rubella, cytomegalovirus, and Toxoplasma gondii have been reported.

Although some studies have reported recurrent infections in as many as 50% of IgA-deficient patients, most of these individuals are healthy. Some patients develop symptoms after an uneventful childhood and early adulthood. Recurrent or chronic upper and lower respiratory tract infections result in bronchiectasis or cor pulmonale in insufficiently treated patients. Gastrointestinal infection with Giardia lamblia infection is common as are a spruelike syndrome, ulcerative colitis, and Crohn disease.

The incidence of autoimmune and collagen vascular diseases, including rheumatoid arthritis, systemic lupus erythematosus, autoimmune hepatitis, hemolytic anemia, and endocrinopathies, is also increased, with reports of up to 25% of patients being affected.

PatientswithundetectablelevelsofIgAantibodiesmaydevelopanti-IgA antibodies after the administration of blood products. Once sensitized, these patients are at risk for anaphylactic reactions if they receive blood products containing even small amounts of IgA. An antibody response to cow's milk protein is also common.

The variability in clinical expression is explained by several factors. Symptoms may be attenuated by an increased excretion of monomeric IgM in these patients' secretions, which helps to compensate for the lack of IgA. Symptoms maybeworsened by the association ofan IgG subclass deficiency.

Intravenous Ig (IVIG) replacement therapy is the treatment of choice for most primary B-cell disorders with hypogammaglobulinemia, including x-linked agammaglobulinemia, common variable immunodeficiency, immunodeficiency with thymoma, and most of the combined immunodeficiencies. However, selective IgA deficiency has no treatment. Therapy should be directed toward the specific disease. Administration of IVIG to patients with IgG subclass deficiency is not recommended unless antibodies are absent or there is no response to prophylactic antibiotics. Gammaglobulin is not used in selective IgA deficiency unless IgG2 subclass deficiency or antibody deficiencyisalsopresent.Theprognosisisthesameastheassociateddisorder.

Suggested Readings

Cooper MA, Pommering TL, Kor´ anyi K. Primary immunodeficiencies. Am Fam Physician. 2003;68:2001–2008.
Makhoul I, Claxton D, Rybka W. Pure B-cell Disorders. Available at: www.emedicine.com/ med/topic216.htm. Accessed March 2, 2007.
National Primary Immunodeficiency Resource Center. Selective IgA Deficiency. Available at: http://www.info4pi.org/faq/index.cfm?Section=faq&CFID=24824785&CFTOKEN= 51564784#24. Accessed March 1, 2007.

Book Source Details

• Book Title: Avoiding Common Pediatric Errors
• Author(s): Anthony D Slonim MD, DrPH; Lisa Marcucci MD
• Year of Publication: 2008
• Copyright Details: Avoiding Common Pediatric Errors, Copyright © 2008 Lippincott Williams & Wilkins.

Other Book Chapters Related to Anemia

Read excerpts from these other book chapters related to Anemia:

Copyright Details: Avoiding Common Pediatric Errors, Copyright © 2008 Williams & Wilkins.

More About Causes of Anemia

• Back to symptom: Anemia: Introduction (review 810 causes)
• Next Book Extract About Anemia: Medications causing Anemia
• All Book Extracts: All Online Book Extracts for Anemia

More About This Book: Title: Avoiding Common Pediatric Errors Authors: Anthony D Slonim MD, DrPH; Lisa Marcucci MD Publisher: Lippincott Williams & Wilkins Copyright: 2008 ISBN: 0-7817-7489-6

 » Next page: Medications causing Anemia

Rate This Website

What do you think about the features of this website? Take our user survey and have your say:

Website User Survey

Medical Tools & Articles:

Next articles:

• Medications causing Anemia
• Videos relating to Anemia
• Drug interactions causing Anemia
• Diagnosis Checklist for Anemia
• Types of Anemia

Tools & Services:

• Bookmark this page
• Related medical articles for Anemia:
• Take a survey relating to Anemia
• Symptom Search
• Symptom Checker
• Medical Dictionary
• Give your feedback

Medical Articles:

• Disease & Treatments Search
• Misdiagnosis Center
• Full list of interesting articles

Forums & Message Boards

• Ask or answer a question at the Boards:
• I cannot get a diagnosis. Please help.
• Tell us your medical story.
• Share your misdiagnosis story.
• What is the best treatment for my condition?
• See all the Boards.

Enter your search terms Submit search form
Search The Web Search wrongdiagnosis.com

Common Health Mistakes

Symptom
Checker

Search Specialists by State and City