Acute acalculous cholecystitis (AAC) is an inflammation of the gallbladder in the absence of demonstrated stones, which is rarely seen in paediatric population. The diagnosis is accomplished mainly through abdominal ultrasonography in the appropriate but usually non-specific clinical picture. Complicated cases need surgical intervention; the medical management is mainly constituted by supportive and antibiotic therapy, as most AAC are observed in the setting of systemic bacterial or parasitic infections. However, AAC has been rarely reported in association with Epstein-Barr virus (EBV) infection, where the gastrointestinal involvement is often mild and thus unrecognised. We report a case of EBV-related AAC associated with unusually severe hepatitis in an immunocompetent and otherwise healthy patient. We describe its benign clinical course, despite the serious liver impairment, by a medical management characterised by the prompt discontinuation of broad-spectrum antibiotics, as soon as EBV aetiology is ascertained, and by the appropriate analgesia and fluid resuscitation.