In the acute and chronic phases, HbSag will always be positive, but antihbc igm is usually positive in the acute phase, but not in the chronic phase.
anti-hbc IgM test and HBsAg test, what is the differentiate between them?
Traditionally, anti-hbc IgM test is used to distinguish between acute and chronic Hepatitis B infection. To me, the most reliable way to distinguish between the two is to wait or test again in 6 months time, unless you are very knowledgeable in this area and have some idea about the time of the incident that causes the infection.