Quantitation of IgA
Indicate the patient's age on the test request form.
Within 1 day
Turnaround time is defined as the usual number of days from the date of pickup of a specimen for testing to when the result is released to the ordering provider. In some cases, additional time should be allowed for additional confirmatory or additional reflex tests. Testing schedules may vary.
Serum
1 mL (adult), 0.4 mL (pediatric)
Red-top tube or gel-barrier tube
Samples suspected of having macroglobulins or cryoglobulins should be drawn and held at 37°C. Samples suspected of containing cold agglutinins should not be refrigerated prior to serum separation from clot.
Temperature
Period
Room temperature
14 days
Refrigerated
Frozen
Freeze/thaw cycles
Stable x3
Excessive lipemia
Evaluate humoral immunity; monitor therapy in IgA myeloma
If samples containing macroglobulins, cryoglobulins, or cold agglutinins are handled at incorrect temperatures, false low values may result.
Immunoturbidimetric
See table.
Age
Range (mg/dL)
Male
0 to 10 d
2-362
11 d to 6 m
8-37
7 to 11 m
12-58
1 to 3 y
21-111
4 to 15 y
52-221
16 to 60 y
90-386
>60 y
61-437
Female
8-32
11-45
19-102
51-220
16 to 70 y
87-352
>70 y
64-422
Increased monoclonal IgA may be produced in lymphoproliferative disorders, especially multiple myeloma and “Mediterranean” lymphoma involving bowel. An IgA monoclonal peak >2 g/dL is a major criterion for myeloma. It may be elevated in a wide range of conditions affecting mucosal surfaces, where IgA is largely produced. Some clinically significant IgA deficiencies have concomitant deficiencies of IgG2 and IgG4. IgA may be decreased in patients with chronic sinopulmonary disease, in ataxia-telangiectasia, or congenitally. Patients with congenital IgA deficiency are prone to autoimmune diseases, and may develop antibody to IgA and anaphylaxis if transfused. IgA levels may rise with exercise and fall during pregnancy.