Case Presentation: A 22-year-old man with Asperger syndrome presented with five days of fever and acute confusion after an episode of pharyngitis. Vital signs were significant for T 39.3°C, HR 120/min, BP 93/57 mmHg, and RR 22/min with O2 sat 94% on 4L. Physical exam was remarkable for thick oral secretions, tenderness to palpation of the right lateral cervical area, and coarse rales in the right middle lobe (RML). He had a leukocytosis of 18.9×10^9/L. CT chest demonstrated RML pneumonia and cavitary, nodular opacities concerning for septic emboli. The patient was admitted for severe sepsis with concern for acute bacterial endocarditis. He was empirically started on Vancomycin and Piperacillin/Tazobactam. A transthoracic echocardiogram did not reveal valvular vegetations. Subsequent transesophageal echocardiogram could not be performed due to respiratory secretions. Blood cultures grew Gram negative bacilli that speciated Fusobacterium necrophorum, prompting work-up for Lemierre’s syndrome. CT neck with contrast revealed a filling defect in the right internal jugular vein (IJV). A venous doppler ultrasound confirmed the presence of IJV thrombosis and thrombophlebitis. The patient later developed a 12 cm abscess in the left triceps area that required surgical drainage. The constellation of clinical findings, imaging, and F. necrophorum bacteremia is consistent with a diagnosis of Lemierre’s syndrome. The patient continued on Piperacillin/Tazobactam before transitioning to meropenem for an allergic reaction. A repeat CT chest showed bilateral septic emboli with central necrosis, necrotizing pneumonia of the RML, and bilateral pleural effusions. This prompted consultations to Interventional Pulmonology and Thoracic Surgery, both of whom recommended conservative management. The patient continued IV antibiotics for 14 days with gradual stabilization and resolution of hypoxia. He was discharged on a 6-week course of Amoxicillin/Clavulanate.

Discussion: Lemierre’s syndrome is a rare and potentially fatal sequelae of oropharyngeal infection. It is characterized by bacteremia, IJV thrombophlebitis, and metastatic septic emboli, most commonly to the lungs.[1] Persistent fever, recent upper respiratory infection, and worsening symptoms should prompt urgent evaluation. Even with treatment, mortality ranges from 5-18%.[2,3] The most common causative agent is Fusobacterium necrophorum, followed by Fusobacterium nucleatum, streptococci, staphylococci, and Klebsiella pneumoniae. The median age of onset is 19 to 22 years with a 2:1 ratio of males to females. Management consists of inpatient IV antibiotics followed by an extended course of outpatient antibiotics. Amoxicillin/clavulanic acid, ceftriaxone, metronidazole, and piperacillin/tazobactam are commonly used agents.[1] Anticoagulation therapy is controversial. Studies have not shown significant benefit in either vessel recanalization or mortality.[4] Drainage of infected cervicofacial tissue and abscesses may be required in up to 50% of cases.[5] Surgical lobectomy for source control is not common practice.

Conclusions: Progression of symptoms after an episode of pharyngitis should prompt a thorough evaluation by clinicians. An acutely ill, young patient with severe sepsis, necrotic lesions to the lungs, and Gram negative bacteremia should raise suspicion for Lemierre’s syndrome. In most cases, long-term antibiotic use without anticoagulation is sufficient to resolve the infection.

IMAGE 1: Right internal jugular vein filling defect, diagnostic of nonocclusive thrombus

IMAGE 2: Left-sided septic embolus, one of many to the patient’s lungs