| [ Summary ] |
The hepatitis B virus (HBV) may be detected in the sera of HBsAg-negative individuals in two situations : the window period and with occult HBV infection. The window period may be shortened to fifteen days with nucleotide amplification assay. However, in some cases, these testing positive for serum HBV-DNA without HBsAg may be overlooked. Occult HBV infection causes liver injury when the HBV genome harbors mutations that reduce HBsAg production or that change HBsAg conformation. Without these mutations, occult HBV infection may cause liver injury in patients undergoing immunosuppressive therapy. |