Baseline Testing Before IVIG Administration
Before initiating IVIG therapy, you must check serum IgA levels to identify IgA deficiency, which carries a risk of severe anaphylaxis from anti-IgA antibodies. 1, 2, 3
Essential Pre-Infusion Laboratory Tests
Mandatory Screening
- Serum IgA levels: This is the single most critical test to prevent life-threatening anaphylactic reactions in IgA-deficient patients who may have developed anti-IgA antibodies 1, 2, 3
- Complete blood count (CBC): Establishes baseline for monitoring hemolysis and leukopenia 4
- Renal function panel: Creatinine and estimated GFR (using MDRD or CKD-EPI) to assess baseline kidney function, as IVIG can cause acute renal failure, particularly in patients with pre-existing renal impairment 4, 5
Additional Baseline Assessment
- Liver function tests: AST, ALT, alkaline phosphatase, total bilirubin, and albumin to establish baseline hepatic function 4
- Serum electrolytes: Sodium, potassium, calcium, phosphorus to monitor for metabolic disturbances 4
- Coagulation studies: PT, PTT, and fibrinogen if using IVIG for hematologic conditions like ITP or acquired hemophilia 6
- Viral serology: HIV, HCV, and HBV testing, particularly for patients with newly diagnosed ITP or immunodeficiency 6, 4
Cardiovascular and Volume Status Evaluation
Cardiac Assessment
- Cardiac function evaluation: Assess for heart failure, recent myocardial infarction, or significant cardiovascular disease before IVIG administration, as volume overload from high-dose IVIG can precipitate congestive heart failure 7, 1, 5
- Baseline electrocardiogram: Document cardiac rhythm and identify pre-existing conduction abnormalities 4
- Fluid status assessment: Evaluate for volume overload risk, especially in patients with cardiac dysfunction who may require divided dosing (1 g/kg daily over 2 days instead of 2 g/kg single dose) 7
Risk Stratification for Complications
High-Risk Features Requiring Special Attention
- Thrombotic risk factors: Age >65 years, obesity, diabetes, hypertension, immobility, or history of thrombosis warrant enhanced monitoring for deep venous thrombosis, pulmonary embolism, and stroke 1, 5, 8
- Renal impairment: Patients with creatinine clearance <30 mL/min or diabetic nephropathy are at increased risk for acute renal failure 4, 5
- Bed-bound status: Immobilized patients have elevated risk of thromboembolic complications 5
Clinical Pitfalls to Avoid
Critical Safety Considerations
- Never skip IgA testing: IgA deficiency with anti-IgA antibodies can cause fatal anaphylaxis; if deficiency is detected, use IVIG preparations with reduced IgA content 1, 2, 3
- Avoid IVIG in acute volume overload: Patients with decompensated heart failure should have cardiac function optimized before IVIG administration 7, 5
- Screen for recent myocardial infarction: IVIG-induced hypotension can occur in patients with recent cardiac events 5
- Assess infection status: Active infections should be documented and treated, as fever during infusion may represent infection rather than IVIG reaction 4, 9
Additional Context-Specific Testing
For Hematologic Indications (ITP, Hemophilia A)
- Platelet count and peripheral smear: Establish baseline thrombocytopenia severity 6
- Direct antiglobulin test (Coombs): Rule out concurrent Evans syndrome 6
- H. pylori testing: For newly diagnosed ITP patients 6
- Bethesda unit level: For acquired hemophilia A to quantify inhibitor titer 6