Reported Causes of False-positive EIA and Immunoblot Tests for HIV Antibody*

EIA

• Cross-reactive antibodies to some human leukocyte antigens (HLA) that develop as the result of prior blood transfusion or during pregnancy
• Auto-antibodies found in some rheumatologic diseases
• Heating of serum
• Freeze-thaw of serum
• Receipt of gamma-globulin
• Recent vaccination (influenza, hepatitis)
• Renal transplantation
• Some liver diseases
• Some cancers
• EBV infection
• Positive RPR tests (syphilis, some autoimmune diseases)
• Technical errors in testing

Immunoblot - Usually giving an indeterminate result

• Antibodies to some HLAs
• Auto-antibodies found in some rheumatologic diseases
• Gammopathies
• Hyperbilirubinemia
• Receipt of gamma-globulin

* Modified from Postgrad Med 1995;98:177