Overview: Immunoglobulin A (IgA) TestIntroduction: The Immunoglobulin A (IgA) Test measures IgA levels to diagnose immune deficiencies or liver disease, causing infections or fatigue. Aligned with 2023 AAAAI guidelines, it uses immunoassays for high accuracy, supporting immune screening. This test is critical for guiding diagnosis, treatment planning, and improving outcomes in immunology for patients with suspected immune or hepatic disorders.
Other Names: IgA Assay, Serum IgA Test.
FDA Status: Laboratory-developed test (LDT), meeting immunology standards for diagnostic accuracy.
Historical Milestone: IgA testing began in the 1960s with immune research. Immunoassay-based methods improved in the 1990s, enhancing diagnostic precision.
Purpose: Measures IgA levels to diagnose immune deficiencies or liver disease, guides treatment, and evaluates patients with infections or fatigue.
Test Parameters: 1. Immunoglobulin IgA
Pretest Condition: No fasting required. Collect serum, plasma, or saliva at any time. Report history of recurrent infections, liver disease, or fatigue.
Specimen: 2-5 mL serum (SST), 2-4 mL plasma (EDTA), or 1-2 mL saliva (sterile container). Transport in a biohazard bag.
Sample Stability at Room Temperature: 8 hours
Sample Stability at Refrigeration: 7 days
Sample Stability at Frozen: 6 months
Medical History: Document recurrent infections, liver disease, fatigue, or family history of immune deficiencies. Include current medications, especially immunoglobulins.
Consent: Written consent required, detailing the tests purpose, immune or liver implications, and potential need for treatment planning.
Procedural Considerations: Uses immunoassays to measure IgA levels. Results are available in 1-2 days, supporting rapid clinical decisions. Performed in laboratories, often for immune or hepatic assessment.
Factors Affecting Result Accuracy: Improper sample handling or contamination can affect results. Recent infections or liver disease may influence IgA levels.
Clinical Significance: Low IgA suggests immune deficiency, guiding immunoglobulin therapy. Elevated IgA may indicate liver disease or chronic infections, requiring further testing.
Specialist Consultation: Consult an immunologist or hepatologist for result interpretation and treatment planning.
Additional Supporting Tests: IgG, IgM, liver function tests, or lymphocyte subset analysis to assess immune or hepatic function.
Test Limitations: Not specific to one condition; clinical correlation is needed. IgA levels vary with age or infections.
References: AAAAI Immune Deficiency Guidelines, 2023; Journal of Allergy and Clinical Immunology, Bonilla FA, 2022.
