Portal Vein Thrombosis Associated With Fusobacterium nucleatum Bacteremia: A Rare Abdominal Variant of Lemierre’s Syndrome

Lemierre's syndrome is a rare but potentially severe complication of bacterial infections that usually affects previously healthy adolescents and young adults. It commonly presents as septic thrombophlebitis of the internal jugular vein and bacteremia following a recent oropharyngeal infection. The most commonly isolated organisms are Fusobacterium necrophorum, followed by Fusobacterium nucleatum and other anaerobes. Atypical Lemierre's syndrome is characterized by thrombophlebitis at sites distant from the head and neck veins and is far less encountered than typical Lemierre's syndrome. Here, we present a case of an elderly African American female with pylephlebitis, a rare abdominal variant of Lemierre's syndrome with extensive portal vein, splenic vein, and mesenteric vein thrombosis following perforated diverticulitis and resultant F. nucleatum bacteremia. She demonstrated complete recovery following appropriate long-term intravenous antibiotics and anticoagulation. This case calls attention to the re-emergence of the rare manifestation of this forgotten disease and highlights improved outcomes with prompt recognition and early treatment.