Following two positive ELISA tests for HIV, which test is expected to confirm the diagnosis?

The most reliable method for confirming a diagnosis of HIV after two positive ELISA tests is the Western blot test. This confirmatory test has a high specificity and is used to verify the presence of HIV antibodies in the bloodstream. The Western blot test detects specific proteins associated with the virus, providing a more definitive confirmation compared to initial screening tests like ELISA, which can sometimes yield false positives.

While the CD4+ T-cell count and PCR test are important in the management and monitoring of HIV infection, they do not serve as definitive confirmatory tests after an initial positive diagnosis. The CD4+ T-cell count measures the immune system's health and is used to assess the impact of HIV on the body, while the PCR (Polymerase Chain Reaction) test detects the viral load but is often used in the context of tracking disease progression rather than confirming initial diagnosis.

A bone marrow biopsy does not play a role in confirming HIV diagnoses. Thus, the Western blot test remains the gold standard for confirming the presence of HIV after initial positive ELISA results.