The remaining 4 patients with a sharp elevation of liver enzyme level but no liver biopsy (serological HBsAg positive, HBeAg positive or negative, HBeAb positive, HBcAb IgG positive and IgM negative or positive, and HBV-DNA elevated) were reported to have an acute exacerbation of CHB, suggesting that the acute exacerbation of CHB may be a major predisposing factor for GBS onset. This evidence concerns the gene CD40LG and Guillain-Barre syndrome.