CD40LG and cytomegalovirus infection: Of the 149 children with primary EBV infection, 40 (26.8%) showed serum EBV VCA IgM and CMV IgM dual positivity, but true CMV infection was confirmed only in 1 child (2.5%) with positive serum CMV antigenemia and positive urine CMV PCR in addition to negative serum CMV IgG antibodies.