CD40LG and viral hepatitis: We ruled out other infectious diseases, autoimmune diseases, immunodeficiency, and tumors after obtaining negative results for tests on cytomegalovirus, T. gondii, adenovirus, viral hepatitis, HIV, mycoplasma IgM, TPPA, fungal G and GM, bacterial hemocultures, autoantibodies, humoral and cellular immunity, and tumor markers, as well as negative urine and stool examinations, and chest and abdomen CT images.