Case Presentation: A 53-year-old male with no prior medical history presented to our institution with a 6-day history of fever and lumbar pain. He denied experiencing a sore throat. Upon examination, conjunctival icterus was observed. No dental caries were detected in the oral cavity. Laboratory analysis revealed an elevated inflammatory response, characterized by a white blood cell count of 34,400/μL and a C-reactive protein level of 16.3 mg/dl. The patient also exhibited severe thrombocytopenia (platelet: 5,000/μL), renal dysfunction (serum creatinine: 2.02 mg/dl), and jaundice (total bilirubin: 3.9 IU/L). Chest and abdominal computed tomography (CT) scans showed multiple pulmonary masses and nodules with a characteristic reversed halo sign and a low-density region in the liver. The patient was admitted to our hospital, and intravenous ceftriaxone was promptly administered. However, the patient’s respiratory failure progressively deteriorated. On hospital day 3, a contrast-enhanced CT scan revealed an enlarged mass with rapid cavitation and an increased bilateral pleural effusion. Additionally, there were contrast defects suggestive of portal vein thrombosis and a liver abscess, although internal jugular venous thrombosis was not identified. Thoracentesis and catheter drainage were executed, yielding purulent pleural effusion. On hospital day 5, blood cultures drawn upon admission confirmed Fusobacterium necrophorum, associated with lung abscess, bilateral empyema, liver abscess, and thrombophlebitis. Consequently, the antibiotic regimen was transitioned from ceftriaxone to sulbactam/ampicillin. Given the inadequate response to medical management, the patient underwent bilateral thoracic drainage for bilateral empyema and simultaneous bilateral decortications via video-assisted thoracic surgery. This was followed by percutaneous drainage of the liver abscess, with resolution of clinical symptoms. The patient was discharged 34 days after admission and transitioned to oral metronidazole, resulting in 4 weeks of antimicrobial therapy. The patient has not experienced any relapse since then.

Discussion: Fusobacterium necrophorum is an anaerobic gram-negative rod primarily associated with Lemierre’s syndrome, pharyngotonsillitis, and peritonsillar abscess. Lemierre’s syndrome typically affects young adults and is characterized by septic thrombophlebitis of the internal jugular vein and metastatic pulmonary abscesses. However, as in our case, invasive F. necrophorum infection without an identifiable source occurs in approximately 30% of F. necrophorum bacteremia cases. These patients tend to be older with comorbidities such as gastrointestinal or urogenital malignancies. While multiple pulmonary abscesses are common in Lemierre’s syndrome, only 15% of patients with invasive infections lacking clear sources exhibit lung involvement. Our case was further complicated by bilateral empyema, a condition typically unilateral and rarely reported. Bilateral empyema refractory to medical therapy necessitates early consideration of surgical intervention. Therefore, hospitalists should provide timely surgical consultation based on the patient’s clinical condition.

Conclusions: We have detailed a case of invasive F. necrophorum infection complicated by lung abscess, bilateral empyema, liver abscess, and thrombophlebitis. Hospitalists play a pivotal role in managing complex cases with atypical clinical manifestations.