Serology test of toxoplasma-immunoglobulin (Ig) G/IgM, quantiferon-tuberculosis assay, rapid plasma reagin, blood cultures for fungus and bacteria, Epstein-Barr viral capsid antigen-IgM, cytomegalovirus (CMV)-IgG/IgM/quantitative polymerase chain reaction (PCR), herpes simplex virus (HSV)-IgG/IgM, anti-human immunodeficiency virus (HIV) antibody (Ab), and aspergillus galactomannan antigen (Ag) turned out to be negative. The gene discussed is CD40LG; the disease is tuberculosis.