CD4 and tuberculosis: He was hepatitis B surface antibody and core total antibody negative, hepatitis C antibody negative, syphilis IgG/IgM negative, quantiferon tuberculosis (TB) gold testing within normal limits (WNL), cytomegalovirus (CMV) IgG and IgM WNL, toxoplasma IgM antibody WNL, human immunodeficiency PCR test negative, and had a CD4 cell count of 641 cells/mm3.