Clinical spectrum of bacteraemic Fusobacterium infections: from septic shock to nosocomial bacteraemia.

BACKGROUND: Fusobacterium species are anaerobic bacteria that relatively rarely cause sepsis with a variable clinical presentation.
METHODS: We reviewed the records of 52 consecutive patients who had Fusobacterium bacteraemia over a 10-y period.
RESULTS: The clinical pictures could be classified into 4 groups: (1) patients who had Lemierre's syndrome with Fusobacterium necrophorum sepsis and internal jugular vein thrombosis, n = 5 (10%); (2) previously healthy patients who had F. necrophorum sepsis without any signs of macroscopic vascular thrombosis (but 5 of them had abscesses), n = 14 (27%); (3) women who had puerperal infections, n = 6 (12%); and (4) patients who were on average older than the patients in the previous groups, who had cardiovascular, pulmonary, neoplastic, or other underlying diseases, n = 27 (52%). Of these latter 27 patients, 23 had nosocomial Fusobacterium nucleatum bacteraemia presenting as a febrile illness associated with chemotherapy or instrumentation.
CONCLUSIONS: Patients with chronic underlying diseases are more likely to be infected with F. nucleatum than F. necrophorum. F. nucleatum bacteraemia may present as a febrile illness without severe symptoms. F. necrophorum caused sepsis mainly in previously healthy individuals. These infections may be accompanied with a jugular vein thrombosis characteristic of Lemierre's syndrome and septic shock. However, F. necrophorum infections present more frequently without any apparent venous thrombosis and may be accompanied by abscesses.