Editing Lemierre's syndrome (section)

==Diagnosis==
Diagnosis and the imaging (and laboratory) studies to be ordered largely depend on the patient history, signs and symptoms. If a persistent sore throat with signs of sepsis are found, physicians are cautioned to screen for Lemierre's syndrome.<ref>{{cite journal | vauthors = Eilbert W, Singla N | title = Lemierre's syndrome | journal = International Journal of Emergency Medicine | volume = 6 | issue = 1 | pages = 40 | date = October 2013 | pmid = 24152679 | pmc = 4015694 | doi = 10.1186/1865-1380-6-40 | doi-access = free }}</ref>

Laboratory investigations reveal signs of a bacterial infection with elevated [[C-reactive protein]], [[erythrocyte sedimentation rate]] and white blood cells (notably [[neutrophils]]). Platelet count can be low or high. Liver and kidney function tests are often abnormal.{{citation needed|date=November 2020}}

Thrombosis of the internal jugular vein can be displayed with [[Medical ultrasonography|sonography]]. Thrombi that have developed recently have low echogenicity or echogenicity similar to the flowing blood, and in such cases pressure with the ultrasound probe show a non-compressible jugular vein - a sure sign of thrombosis. Also color or power Doppler ultrasound identify a low echogenicity blood clot. A CT scan or an MRI scan is more sensitive in displaying the thrombus of the intra-thoracic retrosternal veins, but are rarely needed.{{citation needed|date=November 2020}}

[[Chest X-ray]] and chest CT may show pleural effusion, nodules, infiltrates, abscesses and cavitations.{{citation needed|date=November 2020}}

[[Microbiological culture|Bacterial cultures]] taken from the blood, [[Arthrocentesis|joint aspirates]] or other sites can identify the causative agent of the disease.{{citation needed|date=June 2022}}

Other illnesses that can be included in the [[differential diagnosis]] are:{{citation needed|date=November 2020}}
* [[Q fever]]
* [[Tuberculosis]]
* [[Pneumonia]]