What does Fusobacterium look like?

Fusobacterium is a genus of anaerobic, Gram-negative, non-sporeforming bacteria, similar to Bacteroides. Individual cells are slender, rod-shaped bacilli with pointed ends. Strains of Fusobacterium cause several human diseases, including periodontal diseases, Lemierre’s syndrome, and topical skin ulcers.

Is Fusobacterium a gram-negative bacteria?

Fusobacterium nucleatum, the first Gram-negative bacterium demonstrated to produce polyglutamate.

What is Fusobacterium necrophorum infection?

Fusobacterium necrophorum is a rare causative agent of otitis and sinusitis. Most commonly known is the classic Lemièrre’s syndrome of postanginal sepsis with suppurative thrombophlebitis of the jugular vein.

What are Fusobacterium species?

Fusobacterium is an anaerobic gram-negative bacteria which is often involved in the development of Lemierres syndrome[1], although other bacteria, such as other fusobacteria or Streptococcus, can also be related to this syndrome[2]. The most common species isolated within this genus are F. nucleatum and F. necrophorum.

How do you identify Fusobacterium?

As a genus, Fusobacterium is sensitive to both kanamycin and colistin and resistant to vancomycin. It can be distinguished by its bile sensitivity and metabolism of threonine to propionate. Most species are indole positive and produce butyric acid during the fermentation of glucose.

How common is Fusobacterium?

Fusobacterium spp. bacteremia in our community is uncommon and occurs in approximately 5.5 cases per million population per annum. F. necrophorum occurred in an otherwise young healthy population and was not associated with any mortality.

What is Lemierre syndrome?

Lemierre’s syndrome is a severe illness caused by the anaerobic bacterium, Fusobacterium necrophorum which typically occurs in healthy teenagers and young adults. The infection originates in the throat and spreads via a septic thrombophlebitis of the tonsillar vein and internal jugular vein.

How is Fusobacterium necrophorum treated?

Although Fusobacterium infections are rare, they can become severe if not treated promptly. Appropriate treatment is combination antibiotic therapy consisting of a β-lactam (penicillin, cephalosporin) and an anaerobic antimicrobial agent (metronidazole, clindamycin).

What does Fusobacterium necrophorum do?

F. necrophorum is responsible for 10% of acute sore throats, 21% of recurrent sore throats and 23% of peritonsillar abscesses with the remainder being caused by Group A streptococci or viruses.

How long does Fusobacterium take to grow?

Depending on the strain, it usually takes 2 to 7 days for fusobacteria to grow up on blood agar plates or in broth.

Is Lemierre syndrome curable?

While Lemierre’s syndrome is more treatable today, it can still be a life-threatening condition. The mortality rate for Lemierre’s infections that are in advanced and serious stages is approximately between 5 and 18 percent, per StatPearls.

Where is Fusobacterium necrophorum commonly found?

Fusobacterium species are normal inhabitants of all mucosal surfaces, including the mouth, upper respiratory tract, gastrointestinal tract, and urogenital tract. Worldwide, F. nucleatum is the most common Fusobacterium species found in clinical infections, while F. necrophorum is the most virulent.

What are the colonies of Fusobacterium look like?

When occasional motility occurs presence of peritrichous flagella; Usually no motility occurs. None. Occasionally. Cultures should be stained for spores. Colonies are 1-2mm and are circular to slightly irregular. They may be convex to pulvinate, translucent, often displaying a “flecked” appearance when viewed by transmitted light.

What is the morphology of an Enterobacter cloacae colony?

Morphology: large, smooth, flat colonies with entire margin without beta hemolysis.

What kind of cells do Fusobacterium spp.have?

Fusobacterium spp. can be somewhat variable in their Gram stain and display a range of cellular morphologies from coccoid, pleomorphic spherules (Fusobacterium necrophorum) to rod shaped. Rods can be short with rounded ends or long and thin with pointed ends (F. nucleatum), arrayed end to end (Fig. 249-1C).

Can a Fusobacterium coaggregate with any oral bacteria?

Fusobacterium spp., and particularly F. nucleatum, have been shown to coaggregate with all genera of oral bacteria tested, albeit in one-on-one interaction assays. However, such coaggregation is not indiscriminate; fusobacterial isolates preferentially coaggregate with certain strains over others within each genus [147,158].