Human necrobacillosis, with emphasis on Lemierre's syndrome

Lemierre's syndrome is the classical presentation of human necrobacillosis. It is characterized by a primary infection in the head in a young, previou sly healthy person who subsequently develops persistent high fever and diss eminated metastatic abscesses, frequently including a septic thrombophlebit is of the internal jugular vein. The main pathogen is Fusobacterium necroph orum, an obligate anaerobic, pleomorphic, gram-negative rod. Clinical micro biologists have a key role in alerting clinicians and advising proper antib iotic treatment when the characteristic microscopic morphology of the pleom orphic F. necrophorum is seen in Gram stains from positive anaerobic cultur es of blood and pus. Early diagnosis and prolonged appropriate antibiotic t reatment with good anaerobic coverage are crucial to reduce morbidity and m ortality. F. necrophorum also causes human necrobacillosis with foci caudal to the head, mainly in elderly patients with high mortality related to age and predisposing diseases, such as cancers of the primary focus.