RESUMEN
INTRODUCTION: Infectious mononucleosis may lead to numerous complications. Tonsillar hyperplasia with risk of airway obstruction is well known. Dacryocystitis is a rare but potentially severe complication. OBSERVATION: A 6-year-old child with primary mononucleosis infectious diagnosed 8 days before, developed acute dacryocystitis, with rapid evolution to orbital cellulitis, despite adequate antibiotherapy. Emergency surgical drainage was required. DISCUSSION: Dacryocystitis is a rare and little documented complication of EBV infection. Its acute evolution to orbital cellulitis is possible and potentially severe. Its physiopathology is specific. Patients are initially free of chronic stenosis and epiphora, which express acute obstruction of the lachrymal sac due to general lymphoid hyperplasia.
