HIV Confirmatory Test Explained

Diagnosing HIV involves initial screening tests followed by a confirmatory test to ensure accuracy. A confirmatory test precisely verifies the presence of HIV infection.

Understanding HIV Diagnostic Tests

Different tests serve distinct roles in HIV diagnosis:

• ELISA (Enzyme-Linked Immunosorbent Assay): Often used as an initial screening test. It detects the presence of antibodies produced by the body in response to HIV. A positive result requires further verification.
• PCR (Polymerase Chain Reaction) Test: Can detect HIV genetic material (RNA or DNA). While sometimes used for early diagnosis or viral load monitoring, it's not typically the primary confirmatory test for general diagnosis.
• ESR (Erythrocyte Sedimentation Rate) Test: Measures the rate at which red blood cells settle in a test tube. It indicates inflammation in the body but is non-specific and not used for diagnosing HIV.
• Western Blot: This is the standard confirmatory test for HIV. It specifically identifies antibodies against different HIV proteins, confirming a positive screening result.

Why Western Blot Confirms HIV

The Western Blot test separates HIV proteins by size and then detects if antibodies present in the patient's blood bind to these specific proteins. This detailed analysis provides high specificity, making it the definitive method to diagnose HIV after initial screening tests like ELISA yield positive results.