CD40LG and hepatitis B virus infection: She was born in the US, had never traveled outside of the US and had no other exposures or risk factors for hepatitis B. Specific hepatitis B testing consisting of HBsAg, anti-HBc which is the total immunoglobulin level against the core antigen, anti-Hepatitis B core antigen specific IgM (IgM anti-HBc), hepatitis B e antigen (HBeAg) and antibody to HBeAg (anti-HBe) was performed on day 23 post-IVIG.