CD40LG and Increased total leukocyte count: Complete blood count (CBC): Leukocytosis with a count of 13,000x103 (normal range: 4000-10,000×103), basic metabolic panel (BMP): normal, liver function tests (LFTs): normal, renal function tests: normal, serology for IgM and IgG: Epstein-Barr virus, parvovirus, human herpesvirus type 6, coxsackievirus, and cytomegalovirus: negative, serology for IgM anti-HSV-1: positive, serology for IgG anti-HSV-1: negative, polymerase chain reaction (PCR) for HSV: not performed initially, Tzanck test: not performed initially (Figure 1).