We report the case of an 18-year-old woman who was admitted to the medical intensive care unit in Innsbruck with severe septic shock and respiratory insufficiency following a prolonged infection of the upper airways (pharyngitis, sinusitis). Abscessing pneumonia and bilateral pleural empyema were diagnosed as focus. Cultures of pleural fluids were positive for Fusobacterium necrophorum. In addition to multiple organ dysfunction syndrome (acute lung injury, acute renal failure, disseminated intravascular coagulation), she developed tenderness in the right neck followed by septic arthritis of the right sternoclavicular joint a few days later. Further history revealed a previous period of infectious mononucleosis (EBV infection). The previously healthy patient eventually made a complete recovery after prolonged treatment in the ICU including antibiotic therapy and multiple surgical interventions and drainage. Lemierre's syndrome is characterized by severe infection, with pharyngitis, sepsis and thrombosis of the internal jugular vein, and is most frequently associated with upper airway infection with Fusobacterium necrophorum, often preceded by infection with Epstein-Barr virus which enables bacteria growing in the oral cavity to invade.