Flashcards in Osteomyelitis Deck (28):
1
What are the two ways bone can be infected?
Contiguous osteomyelitis (direct extension)
Hematogenous osteomyelitis (seeded by a bacteremia)
2
What are the two clinical presentations of osteomyelitis?
Acute osteomyelitis (cure possible by antimicrobials alone)
Chronic osteomyelitis (refractory to cure by antimicrobials alone)
3
What are two distinct goals of therapy for osteomyelitis?
cure vs suppression
4
Contiguous osteomyelitis is often seen in the context of bone injury and _________
skin ulceration
5
How does diabetes predispose to osteomyelitis
peripheral neuropathy--> soft tissue and bone injury
venous insufficiency--> decreased healing, less able to get antibiotics to the site of wound
6
Differentiate the sites of involvement of hematogenous osteomyelitis in children vs adults
Pediatrics: long bones (different capillary structure around growth plates in children)
Adults: spine, sternoclavicular joint, pubis symphysis
7
What are the most common etiologic agents of osteomyelitis in neonates vs adults
Neonates: streptococci, S. aureus
Adults: S. aureus, Gram-negative rods
8
How does host response contribute to the pathology of osteomyelitis?
neutrophilic response--> tissue breakdown
pus in vascular channels--> impedence of bloodflow--> local ischemia--> bone necrosis
= dead bone with thrombosed blood supply
9
Diabetic foot infections that lead to osteomyelitis are often _____
polymicrobial- gram +, gram -, anaerobes
10
______ is the most frequently isolated organism in osteomyelitis
S. aureus
11
Orthopedic devices are associated with osteomyelitis caused by _________
Staph epidermidis, coagulase negative
12
Bites are associated with osteomyelitis caused by ______
streptococci or anaerobes, Pasteurella
13
Nosocomial infections are associated with osteomyelitis caused by ______
enterobacteriacaea
14
Inoculation through the sole of a tennis shoe is associated with osteomyelitis caused by _____
Pseudomonas
also IVDU, malignant otitis externa
15
Sickle cell disease is associated with osteomyelitis caused by _______
Salmonella
16
_______ formation is an external hallmark of osteomyelitis
sinus tract, can spontaneously come and go
17
Acute osteomyelitis is a ______ disease, chronic osteomyelitis is a ______ disease
antibiotic, surgical
18
What lab findings are supportive of a diagnosis of osteomyelitis?
anemia of chronic disease
ESR/ CRP elevated
19
What findings will be seen on plain radiographs in osteomyelitis?
Destruction, periosteal elevation, focal osteopenia
** X rays lag about 2 weeks behind infection, cannot always distinguish from trauma
20
_____ has excellent sensitivity but limited specificity in helping to support a diagnosis of osteomyelitis
MRI
21
CT scans are best for imaging ______ in osteomyelitis
bony sequestra, might need to be surgically removed
22
______ is the gold standard for making a diagnosis of osteomyelitis
bone biopsy
23
Bone biopsy should be done when a patient is off _________ for at least 72 hours
antibiotics
24
Describe the general approach to treating acute osteomyelitis
weeks of IV antibiotics with goal of cure, rarely need surgery
25
Describe the general approach to treating chronic osteomyelitis
surgical debridement is key, followed by mop up antibiotics
goal is suppression, meeting individualized patient needs but not cure
26
It is important to avoid ______ antibiotic therapy in managing osteomyelitis
empiric
27
List some parenteral agents commonly used to treat osteomyelitis
- Nafcillin by continuous infusion (S. aureus)
- Vancomycin (MRSA, coag-negative staph, enterococci)
- Penicillin G by continuous infusion (streptococci)
- Ceftriaxone (streptococci, GNR)
- Cefepime (P. aeruginosa, S. aureus (methicillin-susceptible), mixed)
- Piperacillin/tazobactam by continuous infusion (P. aeruginosa, mixed)
28