090514 osteomyelitis

Question 1

osteomyelitis

Answer 1

bone infection

Question 2

categories of osteomyelitis

Answer 2

heamtogenous-from seeding of bone related to previous bacteremia

direct implanation-from penetrating injury

continguous-from direct spread of bacteria from an overlying wound or pressure ulcer

infection of prosthetic device-device implanted in bone

Question 3

diff types of osteomyelitis with regards to how commonly you get them at what age

Answer 3

hematogenous ostemyelitis is more common in children

continugous and prostehtic infec more common in adults

Question 4

when step on nail, which organisms can be implanted in bone?

Answer 4

Pseudomonas aeruginosa

Question 5

pathogens causing hematogenous osteomyelitis

Answer 5

S. aureus
Strep species
gram negatives
Mycobastcterium tuberculosis
Salmonella species

Question 6

pathogens causing contiguous osteomyelitis

Answer 6

S aureus
gram negatives
Strep species
anaerboes
Candida species

Question 7

pathogens causing prostehtic joint infections of osteomyleitis

Answer 7

COAGULASE NEGATIVE staph
S aureus
gram negatives
Strep species

Question 8

does osteomyelitis often cause chronic infections that are difficult to eradicate?

Answer 8

yes

Question 9

damage to the periosteum can result in

Answer 9

pieces of dead bone (sequestrum) or
new external bone (involucrum)
local abscesses (brodie's abscesses)

Question 10

for diagnosis of osteomyelitis, what imaging can be used?

Answer 10

XRs not good for early infections, may be effective 50% of the time at later infections

Bone/WBC scans and MRI are good

Question 11

how can you determine the bacteria causing osteomyelitis

Answer 11

bone biopsy
blood culture (if hematogenous osteomyelitis)

Question 12

swab culture from open ulcer vs bone biopsy of bone with osteomyelitis underneath–what do they show about the bacteria?

Answer 12

the bacteria in the two samples may be entirely different

Question 13

treatment of infections of prosthetic materials

Answer 13

are particularly difficult–oftentimes the protehsis has to be taken out

Question 14

where can biofilms develop?

Answer 14

bone or prosthetic material (particularly on hard surfaces)

Question 15

organisms in biofilms are

Answer 15

different from those of planktonic, or suspended, organisms

Question 16

standard treatment for osteomyelitis

Answer 16

generally 6 wks IV antibiotics ( in some cases months of oral antibiotics may be needed, like for prothetic joint infec. *note: sometimes, even after 6 months of oral antibiotics, a prosthetic joint will still have to be removed)

if antibiotics alone don’t work, surgery may be needed to remove sequestra or protheses

Question 17

what antibiotic is very useful for treating biofilm organisms?

Answer 17

rifampin

Question 18

in the case of an ulcer that is open and you can actually see bone through it-how can you treat?

Answer 18

surgeon would have to put covering over the bone so new organisms can’t keep growing over the bone-otherwise you would get resistant organisms and antibiotics wouldn’t work