Lemierre's Syndrome Due to Klebsiella pneumoniae Results in Pulmonary Abscess Complications in a Patient With Diabetes: A Rare Case Report.

Background: Lemierre's syndrome (LS), first described by Andre Lemierre in the early 20th century, is a rare but potentially life-threatening condition typically caused by Fusobacterium necrophorum. However, recent literature has reported cases of LS caused by various other bacteria, including Klebsiella pneumoniae. In this report, we present a rare case of LS in a patient with diabetes caused by K. pneumoniae. Case Report: A 62-year-old Vietnamese male with a history of type 2 diabetes mellitus, presented with an 8-day history of progressive left neck swelling, fever, dysphagia, odynophagia, and reduced appetite. Despite initial antibiotic therapy, his condition deteriorated, leading to pulmonary abscesses and septic shock. Abscess content culture revealed K. pneumoniae. The patient required intubation, mechanical ventilation, and surgical drainage of the neck abscess. Treatment with meropenem, along with glycemic control, led to clinical improvement. The patient was subsequently extubated, achieved complete wound healing, and was discharged with normal biochemical parameters. Conclusion: This case highlights that LS can be caused by pathogens not initially outlined by Andre Lemierre, such as K. pneumoniae. Clinicians should consider a broader spectrum of causative organisms when there is a strong clinical suspicion of LS and adjust antimicrobial coverage accordingly. The association between K. pneumoniae-related LS and diabetes mellitus warrants further investigation, as current evidence suggests that diabetes may predispose patients to this particular pathogen.