Pulmonary empyema caused by co-infections of Mycoplasma pneumoniae and Fusobacterium necrophorum: A rare case of lemierre syndrome

Lemierre syndrome, also known as post-anginal septicemia or necrobacillosis, It is characterized by bacteremia, internal jugular vein (IJT) thrombosis, and metastatic septic emboli secondary to acute pharyngeal infections. The disease is easily forgotten by modern physicians. The causative agents of Lemierre syndrome include anaerobic bacteria, Streptococcus, Staphylococcus, and Klebsiella pneumoniae. Here, we reported a rare case of Lemierre syndrome in a patient with acute pharyngitis, who was complicated by bilateral otitis media and pulmonary empyema caused by co-infections of Mycoplasma pneumoniae and Fusobacterium necrophorum. The patient was proved by imaged study and successfully treated by chest tube drainage and antibiotic combination therapy. A 19-year-old male patient was admitted to our hospital with a 3-day history of fever, sore throat and dyspnea. On admission, consciousness was clear and his temperature was 39.2 C. Physical examination showed redness, swelling of pharyngeal mucosa. White blood cell count (WBC) was 32020/mm with 89% neutrophils. Serum level of C-reactive protein was 36.2 mg/dL, GOT 65 U/L, GPT 123 U/L, LDH 423 U/L. The rapid test of influenza A & B showed negative finding. Initially, he received amoxicillin/clavulanate 1000 mg/200 mg intravenously q 6 h as empiric therapy. But on the admission Day 2, the fever persisted and bilateral ear canal had purulent discharge. On the admission Day 3, the chest X-ray and CT scan showed infiltration of right lower lobe of lung with pleural effusion (Fig. 1A and B) and left internal jugular vein thrombosis (Fig. 1C). The patient received thoracocentesis and the pleural fluid analysis showed exudate and turbid color, which revealed WBC count 760/mm with 97% neutrophils, LDH 2107 U/L, total protein 5.4 g/dL (serum 6.4 g/dL), glucose 10 mg/dL (serum