No abstract available. Article truncated at 150 words. A previously healthy 18-year-old girl was evaluated at an urgent care center for a three-day history of sore throat, fever, nausea, vomiting, diarrhea, and myalgias; the diagnosis of influenza was made at that time. Four days later, she presented to our Emergency Department with sore throat, left sided neck pain and swelling, productive cough, fever, worsening dyspnea, and pleuritic chest pain. On examination her temperature was 36.9 C, heart rate was 142 beats per minute, and respiratory rate was 18 breaths per minute. She had enlarged tonsils without exudates, cervical and submandibular lymphadenopathy, and tenderness of her left lateral neck. Lung examination showed increased work of...