Lemierre syndrome.

Lemierre's syndrome is rare and characterized by an oropharyngeal infection with thrombophlebitis of the internal jugular vein (IJV). Septic microemboli can spread to the lungs or abdomen. This case describes a patient who presented with a sore throat, unilateral swelling on the neck and diffuse abdominal pain. Imaging showed a thrombus in the right IJV. The patient developed septic shock and was treated with antibiotics, anticoagulants, and intensive care support. The most common causative organism is Fusobacterium necrophorum. Early diagnosis and treatment are crucial for reducing mortality.