IgA Subclasses

IgA Subclasses

Test Code

34188
82784, 82787 (x2)
34188
82784, 82787 (x2)
In-home collection may be available in your area for purchase through Quest Mobile.

Clinical Significance

IgA Subclasses - IgA, the predominant immunoglobulin secreted at mucosal surfaces, consists of 2 subclasses. IgA1 is the major subclass and accounts for 80% of total IgA in serum, whereas IgA2 is the major subclass in secretions such as milk.
Low concentrations of IgA2 with normal IgA1 levels suggest an IgA2 deficiency.
Antigenic sites on the IgA subclasses are responsible for the anaphylactic transfusion reactions experienced by some patients totally deficient in either IgA1 or IgA2. After repeated transfusions, such patients may produce antibodies to these antigens. Thus, IgA subclasses are useful in evaluating ...

Test Resources

None found for this test
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Test Details

Includes

  • IgA1, IgA2, and IgA, Serum

Patient Preparation

Fasting preferred

Methodology

Immunoturbidimetry

Reference Range(s)

IgA1
6-11 months1-115 mg/dL
1 year3-120 mg/dL
2 years7-132 mg/dL
3 years11-143 mg/dL
4-7 years23-175 mg/dL
8-11 years33-204 mg/dL
12-17 years47-249 mg/dL
≥18 years46-378 mg/dL
  
IgA2
6-11 months0-19 mg/dL
1 year0-23 mg/dL
2 years1-23 mg/dL
3 years1-25 mg/dL
4-7 years2-33 mg/dL
8-11 years2-37 mg/dL
12-17 years4-50 mg/dL
≥18 years13-91 mg/dL
   
IgA, Serum
Cord Blood1-3 mg/dL
1-28 days2-40 mg/dL
1-3 months3-40 mg/dL
4-6 months7-47 mg/dL
7-11 months12-53 mg/dL
1 year20-73 mg/dL
2 years20-99 mg/dL
3-5 years22-140 mg/dL
6-8 years31-180 mg/dL
9-11 years33-200 mg/dL
12-16 years36-220 mg/dL
17-60 years47-310 mg/dL
≥61 years70-320 mg/dL

LOINC® Codes, Performing Laboratory

IgA1, IgA2, and IgA, Serum
Fasting preferred

Methodology

Immunoturbidimetry

Reference Range(s)

IgA1
6-11 months1-115 mg/dL
1 year3-120 mg/dL
2 years7-132 mg/dL
3 years11-143 mg/dL
4-7 years23-175 mg/dL
8-11 years33-204 mg/dL
12-17 years47-249 mg/dL
≥18 years46-378 mg/dL
  
IgA2
6-11 months0-19 mg/dL
1 year0-23 mg/dL
2 years1-23 mg/dL
3 years1-25 mg/dL
4-7 years2-33 mg/dL
8-11 years2-37 mg/dL
12-17 years4-50 mg/dL
≥18 years13-91 mg/dL
   
IgA, Serum
Cord Blood1-3 mg/dL
1-28 days2-40 mg/dL
1-3 months3-40 mg/dL
4-6 months7-47 mg/dL
7-11 months12-53 mg/dL
1 year20-73 mg/dL
2 years20-99 mg/dL
3-5 years22-140 mg/dL
6-8 years31-180 mg/dL
9-11 years33-200 mg/dL
12-16 years36-220 mg/dL
17-60 years47-310 mg/dL
≥61 years70-320 mg/dL

Preferred Specimen(s)

2 mL serum

Minimum Volume

1 mL

Transport Container

Transport tube

Transport Temperature

Room temperature

Specimen Stability

  • Room temperature: 5 days
  • Refrigerated: 15 days
  • Frozen: 30 days

Reject Criteria

Gross hemolysis • Lipemia

Setup Schedule

2 mL serum
1 mL
Transport tube
Room temperature
Room temperature: 5 days
Refrigerated: 15 days
Frozen: 30 days
Gross hemolysis • Lipemia
In-home collection may be available in your area for purchase through Quest Mobile.
Test Details

Clinical Significance

Test Resources

Reference ranges are provided as general guidance only. To interpret test results use the reference range in the laboratory report.

The CPT codes provided are based on AMA guidance and are for informational purposes only. CPT coding is the sole responsibility of the billing party. Please direct any questions regarding coding to the payer being billed.

This material contains content from LOINC® (http://loinc.org). The LOINC Table, LOINC Table Core are copyright © 1995-2019, Regenstrief Institute, Inc. and the Logical Observation Identifiers Names and Codes (LOINC) Committee and is available at no cost under the license at http://loinc.org/license.

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