CD40LG and Thrombocytopenia: Finally, among 115 cases hospitalized in Thailand for fever of unknown origin (FUO), one appeared IgM- and IgG-positive by HTNV ELISA and IgG-positive by HTNV IFA, showing acute encephalitis, thrombocytopenia, coagulation anomalies, and elevated liver transaminases, now commonly called “transaminitis” [48].