Osteomyelitis Flashcards
Osteomyelitis has high morbidity in those with these complications.
(causing poor blood flow) diabetics peripheral vascular disease pressure ulcers sickle cell trauma injections drug use
Which are the two routes by which a bone can be infected in osteomyelitis?
contiguous osteomyelitis- direct extension from soft tissues or joints
hematogenous osteomyelitis- bacteremia or fungemia seeds the bone
Which sites are most common infected with ostomyelitis in adults v. kids?
pediatrics: long bones
adults: spine (most common)
both may call for a endocarditis work up
In what ways is the host response a detriment in the case of osteomyelitis?
local PMN cytokines promote osteolysis and PMN proteolyic enzymes act as osteoclast agonists
pus spreads into vascular channels causes increased intraosseous pressure, impeding blood flow, reducing healing and causing ischemia/necrosis
Regarding osteomyelitis, what do the terms acute and chronic mean regarding treatment?
acute means treatment with antibiotics and surgical debridement is rarely needed
Regarding osteomyelitis, what do the terms acute and chronic mean regarding treatment?
acute means treatment with antibiotics and surgical debridement is rarely needed
chronic usually requires surgical debridement to remove dead and infected bone in order to facilitate healing on top of antibiotics
What are the clinical signs of a bone infection?
pain, warmth, swelling, loss of function, often helpful to probe the ulcer or sinus; check circulation
**sinus tract formation-intermittent drainage from the bone
What lab test would support a diagnosis of osteomyelitits?
WBC is usually normal or middle elevated
anemia of chronic disease is common
inflammatory markers is often elevated but variable
Which imaging modality is best for osteomyelitis?
MRI has excellent sensitivity, but specificity can be limited
plain films lag 2-3 weeks behind infection but will show destruction, periosteal elevation and focal osteopenia (note loss of sharp cortical borders)
What is the gold standard on diagnosis of osteomyelitis?
bone biopsy- should be obtained in all cases (percutaneous, during surgical debridement and 72hrs off abx)
send for gram stain and culture, histopathology if generous sample
What is the gold standard on diagnosis of osteomyelitis?
bone biopsy- should be obtained in all cases (percutaneous, during surgical debridement and 72hrs off abx)
send for gram stain and culture, histopathology if generous sample
What is the most frequently isolated organism for any type of osteomyelitis?
S. aureus is most frequently isolated
diabetic foot related osteomyelitis is often polymicrobial
Match the following microbes with their corresponding route of infection: S. epidermis Strep/anerobes P. aeruginosa Salmonella Aeromonas hydrophilia Pasturella multocida Eikenella corrodens
S. epidermis- foreign body, prosthetic joint
Strep/anerobes- bites
P. aeruginosa- truama through sole of tennis shoe, IV drugs
Salmonella- sickle cell
Aeromonas hydrophilia-fresh water trauma
Pasturella multocida- animal bites
Eikenella corrodens- human bites
Describe situations in which you would like to cure or merely suppress osteomyelitis infection.
abx can only treat tissue that they can reach so if debridement required in order to treat is so exte
Describe situations in which you would like to cure or merely suppress osteomyelitis infection.
abx can only treat tissue that they can reach so if debridement required in order to treat is so extreme as to affect functionality in ways that are not clinically suitable, then suppression with meds may be prefereable
