All other microbiological and virological analyses, including HSV-1/2 (PCR in peripheral blood (PB), BF, throat wash and eye smear negative, HSV1/2-IgM and IgG negative, serology negative also 2 years before), Epstein-Barr virus (EBV, DNA in PB 2260 copies/ml, limit of detection 1000 copies/ml, PCR in BF and throat wash negative, EBNA1-IgG 72,9; VCA-IgG > 750; EBV-IgM negative, tested twice 3 days apart), cytomegalovirus (CMV, PCR negative in PB, BF and throat wash), were not indicative of infection or reactivation. Here, CD40LG is linked to infection.