Microbiology Flashcards
where would you see haematogenous osteomyelitis and who is it more common in
children with long bones or adult vertebrae
when would you see contiguous osteomyelitis and who is it more common in
younger patients with injury/surgery
older patients with vascular insufficiency/pressure sores
treu/false - for osteomyelitis the best urgent management is empirical antibiotics
false - never unless the patient is septic
microbes in open fracture osteomyelitis
s aureus
gm -ves
polymicrobial
microbes in diabetic foot osteomyelitis
polymicrobial, may be faecal bacteria
microbes in haematogenous osteomyelitis
staph aureus
microbes in sickle cell osteomyelitis
s aureus and samonella
unusual osteoomyelitis sites
clavicle
osteitis pubis - athletes and post surgery
microbes in vertebral osteomyelitis
staph aureus and coag -ve staph
risk factors for vertebral osteomyelitis
PWID GU infection IV line post op primary bacteraemia
true/false - prosthetic joint infections are biofilm forming
true
Organisms in prosthetic joint infection
coag -ve staph - post 3 months staph aureus - 1-3 months propionibacterium acnes gram -ves, ecoli, pseudomonas - may be first 3 months or after corynebacterium - post 3 months cutiibacterium acnes
risk factors for prosthetic joint infection
comorbidity
prior arthroplasty
surgical site infection
pathology of osteomyelitis
infection begins to form an abscess in blood rich bone and then moves to cortical bone to form sequestrium, and then may form a sinus
organisms in pyomyositis
90% staph but in immunosuppressed may be pseudomonas, beta haemolytic strep or enterococcus
what microbe may lead to myonecrosis and what does it form in bone
clostridium
gas
organisms of septic arthritis
staph aureus strep n gonorrhoea h influenzae in school age anaerobes
cause of tetanus and microbiology
clostridium tetani
gram +ve strict anaerobe rod
how does tetanus act to cause disease
neurotoxins from spores bind to inhibitory neurons to prevent neurotransmitter release
antibiotic for s aureus
flucloxacillin
antibiotic for s epidermidis
vancomycin
antibiotic for strep pyrogenes
doxycycline
antibiotics for gram -ves
clindamycin
antibiotics for anaerobes
co-trimoxazole/metronidazole
useful blood tests in osteomyelitis?
blood culture
CRP
ESR/PV
WCC
useful imaging in osteomyelitis and downfall?
x rays - has to be advanced
MRI - overdiagnoses
technetium scan - not any really
true/false - blood work is very useful in chronic osteomyelitis
false
easily measurable prophylaxis to prevent prosthetic joint infection
clean air theratre
local antibiotics in cement
systemic antibiotics
duration of surgery
hard to measure prophylaxis in prosthetic joint infection
theatre discipline
time in washing hands
surgical technique
