Management of Elevated IgA Levels
For isolated elevated IgA without symptoms, no specific treatment is required; the focus should be on identifying and treating any underlying disease that may be causing the elevation. 1, 2
Initial Diagnostic Approach
The evaluation of elevated IgA is fundamentally about finding the underlying cause rather than treating the IgA elevation itself. The following workup should be performed:
Complete Immunoglobulin Assessment
- Obtain a complete immunoglobulin panel (IgG, IgA, IgM) to determine if this is an isolated IgA elevation or part of broader hypergammaglobulinemia. 2 This distinction is critical because it changes the differential diagnosis significantly.
Key Clinical Contexts to Evaluate
Autoimmune Hepatitis:
- A selectively elevated IgG in the absence of IgA and IgM elevation is particularly suggestive of autoimmune hepatitis, though IgA can also be elevated in this condition. 3, 2
- Order liver function tests and autoantibody testing including ANA and smooth muscle antibodies (SMA). 2
- If autoimmune hepatitis is confirmed, immunosuppressive therapy with corticosteroids and/or azathioprine is the treatment. 3, 2
Celiac Disease:
- Screen with anti-tissue transglutaminase (tTG) IgA antibodies, particularly if gastrointestinal symptoms are present. 1, 2
- If positive, refer to gastroenterology for small bowel biopsy confirmation. 2
- Treatment is a gluten-free diet if celiac disease is confirmed. 2
Serious Pediatric Conditions:
- In children, extremely elevated IgA (>3 SD above mean for age) should raise suspicion for severe immune defects, chronic rheumatic disease, or inflammatory bowel disease. 4
- These conditions were found in 73.5% of pediatric patients with hyper-IgA versus only 8% in controls with normal IgA. 4
When No Treatment Is Needed
For IgA levels in the high-normal range (such as 349 mg/dL, which falls within the typical 70-400 mg/dL adult reference range), no intervention is required if the patient is asymptomatic. 1 This represents a borderline elevation without clinical significance in the absence of symptoms. 1
Common Pitfalls to Avoid
- Do not confuse elevated IgA with IgA deficiency. IgA deficiency (defined as <0.07 g/L after age 4) is the most common primary immunodeficiency and requires completely different management considerations. 5, 6
- Do not treat the IgA number itself. There is no therapy to lower IgA levels; treatment is always directed at the underlying condition causing the elevation. 1, 2
- Do not overlook medication-induced changes. Certain drugs including phenytoin, carbamazepine, valproic acid, sulfasalazine, gold, penicillamine, hydroxychloroquine, and NSAIDs can affect IgA levels. 7