EBV and CMV infections. Infectious mononucleosis

1. Big picture

Infectious mononucleosis is a clinical syndrome, most commonly caused by Epstein–Barr virus (EBV), and less commonly by cytomegalovirus (CMV), acute HIV, toxoplasmosis, or other infections.

The classic exam pattern is:

Teenager/young adult
+ fever
+ sore throat/pharyngitis
+ posterior cervical lymphadenopathy
+ fatigue
+ atypical lymphocytosis
+ mild hepatitis/splenomegaly
= infectious mononucleosis, usually EBV

The practical dangers are airway obstruction from tonsillar enlargement, splenic rupture, misdiagnosis as bacterial tonsillitis, and missing CMV disease in immunocompromised patients.