• Atopy
• Sinopulmonary infections
• Gastrointestinal infections (especially Giardia lamblia)
• Crohn disease
• Ulcerative colitis
• Sprue
• Autoimmune illnesses
  • Arthritis
  • Lupus
  • Immune endocrinopathies
  • Autoimmune hematologic conditions
• Chronic active hepatitis

• 18q syndrome
• Partial deletions in the long or short arm, and ring forms of chromosome 18
• Also associated with: HLA-A1, HLA-A2, B8, and Dw3.

• Respiratory tract infections
• Gastrointestinal tract infections
• Atopy

• Toxic, environmental, drugs
  • Penicillamine and anticonvulsants can induce IgA deficiency.
• Genetic/metabolic
  • X-linked agammaglobulinemia (Bruton)
  • Common variable immune deficiency
  • Severe combined immune deficiency
  • Ataxia telangiectasia
  • DiGeorge syndrome
  • Chronic mucocutaneous candidiasis
  • Nezelof syndrome
  • Selective IgG2 deficiency
• Miscellaneous
  • Patients may be completely healthy and IgA deficiency may be an incidental finding.
• Common causes: may be the result of decreased synthesis or impaired differentiation of IgA B-lymphocytes into IgA plasma cells

Question: Does the patient have frequent sinopulmonary infections?
Significance: Patients with IgA deficiency can have frequent sinopulmonary infections.

Question: Does the patient have frequent gastrointestinal infections?
Significance: Patients with IgA deficiency can have frequent gastrointestinal infections.

Question: Does the patient have allergies?
Significance: Patients with IgA deficiency tend to be allergic.

Question: Does the patient have any autoimmune diseases?
Significance: Patients with IgA deficiency have an increased incidence of autoimmune diseases.

Question: Can healthy patients have IgA deficiency?
Significance: Approximately 30% of patients with IgA deficiency are completely healthy.

Finding: Cobblestoning of the conjunctiva
Significance: Cobblestoning of the conjunctiva is caused by allergic inflammation in the eyes. Allergies are associated with IgA deficiency.

Finding: Allergic shiners
Significance: Allergic shiners are the result of allergies. Allergies are associated with IgA deficiency.

Finding: Serous otitis media
Significance: Serous otitis may be the result of recurrent ear infections. Increased ear infections can be seen in IgA deficiency. Furthermore, serous otitis media can be secondary to allergies, which is also associated with IgA deficiency.

Finding: Pain on palpation of the sinuses
Significance: Recurrent sinus infections are associated with IgA deficiency.

Finding: Pneumonia
Significance: An increased frequency of pneumonia is associated with IgA deficiency.

Finding: Swollen joints
Significance: An increased frequency of autoimmune diseases are associated with IgA deficiency.

• Measure serum IgA level.
• If the patient is IgA deficient, exclude other conditions associated with IgA deficiency.

Test: Serum IgA level
Significance: A patient is considered deficient if the serum IgA level is less than 5 mg/dL.

Test: Total immunoglobulins
Significance: If normal, this study would help rule out X-Linked agammaglobulinemia (Bruton), common variable immunodeficiency, and severe combined immunodeficiency.

Test: IgG subclasses
Significance: This study would help rule out an associated IgG2 subclass deficiency.

Test: Lymphocyte mitogens
Significance: This is a functional lymphocyte study. If normal, this study would help rule out common variable immunodeficiency, severe combined immunodeficiency, ataxia telangiectasia, DiGeorge syndrome, and Nezelof syndrome.

Test: Lymphocyte Candida antigen stimulation
Significance: No response to Candida in vivo is consistent with chronic mucocutaneous candidiasis.

• Suggestion that IgA deficiency may be part of a more complex immune deficiency. An allergist/immunologist can assist with an appropriate immunologic evaluation.
• IgA deficiency associated with autoimmune disease. Evaluation and treatment by a rheumatologist would be indicated.
• Patient likely to need a blood transfusion. There is an increased incidence of anaphylaxis to IgA-containing blood products when administered to IgA-deficient patients. The allergist can help select appropriate blood products for these patients.

• Recurrent infections should be treated aggressively with broad-spectrum antibiotics.
• Antibiotic prophylaxis to prevent recurrent sinopulmonary infections is often indicated.
• Intravenous gamma globulin is not indicated.

• Sinopulmonary infections
• Gastrointestinal infections
• Autoimmune diseases
• Inflammatory bowel disease

Q: What is the recurrence risk for a couple with an affected child?
A: It depends on the mode of inheritance. Most commonly, the mode of inheritance is autosomal dominant and the risk would be 50%. However, the expressivity is variable and the patient’s phenotype may not be that of an IgA-deficient person.

Q: Does the patient take any medications?
A: IgA deficiency can be induced by some anticonvulsants and by penicillamine.

Q: Should IgA patients wear medical alert bracelets?
A: Yes. These patients can have anaphylaxis if administered blood products containing IgA. In an emergency situation, this is important information for the caregivers to know.

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Middleton E, Reed CE, Ellis EF, Adkinson NF, Yunginger JW, Busse WW. Allergy principles and practice, 4th ed. Philadelphia: Mosby, 1993.

Rankin EC, Isenberg DA. IgA deficiency and SLE: prevalence in a clinic population and a review of the literature. Lupus 1997; 6(4):390–394.

Sites DP, Terr AI, Parslow TG. Basic and clinical immunology, 8th ed. Englewood Cliffs, NJ: Prentice Hall, 1994.

Smith CA, Driscoll DA, Emanuel BS, McDonald-McGinn DM, Zackai EH, Sullivan KE. Increased prevalence of immunoglobulin A deficiency in patients with the chromosome 22q11.2 deletion syndrome (DiGeorge syndrome/velocardiofacial syndrome). Clin Diagn Lab Immunol 1998; 5:415–417.