A 3.5-year-old healthy boy with 4 days of fever was referred to the emergency department for respiratory distress. The physical examination was remarkable for stupor, tachycardia, tachypnea, and dyspnea. Initial blood tests showed pancytopenia. He rapidly developed torticollis. Computerized tomography of the neck revealed a thrombus in the internal jugular vein. A presumptive diagnosis of Lemierre's syndrome was made and he was started on antibiotics and anticoagulation. He subsequently developed adult respiratory distress syndrome and required high frequency oscillatory ventilation for 9 days. Blood cultures were positive for Fusobacterium necrophorum. Screening for hypercoagulability revealed 2 known risk factors: a mutation in the prothrombin gene and elevated lipoprotein a.