2017 Volume 66 Issue 6 Pages 691-695
The Epstein–Barr virus (EBV), a human herpes virus, is a causative agent of infectious mononucleosis (IM). Although IM is diagnosed on the basis of clinical manifestations, it is difficult to differentiate it from tonsillitis in children with atypical clinical findings. Recently, cell-free EBV DNA has been detected in the plasma of patients with IM. An 18-year-old man was examined by a doctor at a local clinic for complaints of pyrexia and sore throat. Because he was considered to suffer from bacterial tonsillitis, he was given β-lactam antibiotics. Afterwards, he was transferred to a local hospital with the chief complaints of continuous fever for 3 days, sore throat and erythematous rash. The results of his blood tests on admission included the following: leukocyte count, 20,200/mm3 (69% lymphocytes, 0.0% atypical lymphocytes); transaminase levels, within the normal range; and C-reactive protein (CRP) level, 0.2 mg/dL. To differentiate between IM and tonsillitis, we performed a polymerase chain reaction (PCR) assay of EBV using blood lymphocyte and plasma samples, which showed positivity for the virus. Therefore, the patient was diagnosed as having acute IM. PCR assay of EBV using plasma samples is an advantageous method for the rapid and accurate diagnosis of infectious mononucleosis in cases lacking the typical clinical manifestations.
