CPT® Code 86704

The CPT® Code 86704 refers to the testing of a blood sample for the presence of hepatitis B core antibody (HBcAb), which is a critical marker in the diagnosis and management of hepatitis B virus (HBV) infections. Hepatitis B is a viral infection that leads to inflammation of the liver and can manifest in both acute and chronic forms. The core antibody is produced by the immune system during and after an acute HBV infection, and it can also be present during the chronic phase of the disease. This test measures the total HBcAb, which includes both IgG and IgM antibodies, using a chemiluminescent assay. It is important to note that this test does not differentiate between the two types of antibodies; therefore, it cannot specify whether the infection is in the acute or chronic phase. The presence of IgM antibodies typically indicates an initial phase of infection, while IgG antibodies are associated with later stages. For a more specific diagnosis of an acute infection, the CPT® Code 86705 is utilized, which specifically tests for the IgM antibody to HBcAb.