[A fatal case of acute mediastinitis caused by periodontal infection].

A 57-year-old man had suffered from poorly controlled diabetes mellitus and liver cirrhosis due to alcohol and hepatitis C for about 10 years. He developed fever and swelling of the right cheek and neck due to periodontal infection. The symptoms worsened in spite of antibiotic therapy and were accompanied by dyspnea. He was therefore referred to our hospital. Chest radiographs and computed tomographs revealed widening of the superior mediastinum, pulmonary infiltrates and right pleural effusion. He was diagnosed as having mediastinitis, right pyothorax and pneumonia caused by periodontal infection. Tracheotomy and mechanical ventilation were performed. Antibiotic therapy resulted in improvement of the mediastinitis and pyothorax. However, renal and liver dysfunction developed and the patient died of multiorgan failure after 35 days of hospitalization. Death due to periodontal infection is rare. We give a review of the literature.