infections Flashcards
what is acute osteomyelitis
inflammation of bone and medullary cavity usually located in a long bone
what is the common cause of acute osteomyelitis
staph aureus
what are the investigations of acute osteomyelitis
MRI
bone biopsy = gold standard
stick a probe in and see if it touches bone
look and see if bone is visible
what is the treatment of acute osteomyelitis, when should it be carried out
treatment should take place once the organism is identified
debridement
specific antibiotics for 6 weeks
what are the two ways chronic osteomyelitis can occur
pus can enter into the joint cavity
pus can enter into the periosteum
what does chronic osteomyelitis result in
involucrum
what is involucrum, what causes it
new layer if bone growth outside the existing bone
this is due to the stripping off of the periosteum by the accumulation of pus within the bone, the new bone then grows from this periosteum
what are the investigations of chronic osteomyelitis
X-ray
MRI
what is the treatment of chronic osteomyelitis
not all require surgery: possible to live with it and just treat the flare ups
what is the spread of vertebral osteomyelitis
haematogenous
what is vertebral osteomyelitis associated with
epidural
psoas abscess
what are the causes of vertebral osteomyelitis
IVDU
IV
GU infection
post-op
what are the symptoms of vertebral osteomyelitis
fever in 50%
insidious pain/tenderness
raised inflammatory markers
what are the investigations of vertebral osteomyelitis, when would they be done
MRI
biopsy: repeat if fail to get info
open biopsy = if 2 x biopsy have failed
what is the treatment of vertebral osteomyelitis
drain abscesses
specific antibiotics for 6 weeks
repeat MRI
when would a repeat MRI be used in the treatment of vertebral osteomyelitis
unexplained increase in inflammatory markers
increasing pain
new anatomically related symptoms
who is affected by haematogenous osteomyelitis
children elderly IVDU dialysis patients patients with central lines
what is septic arthritis
pus in the joint
what is the spread of septic arthritis
haematogenous
metaphyseal
what are the investigations of septic arthritis
microscopy
blood culture if pyrexial
exclude gout
what is the treatment of septic arthritis
high dose flucloxacillin = presumptive to treat staph aureus + ceftriaxone if <5
adjust antibiotics when organism is confirmed
what is pyomyositis
bacterial infection of skeletal muscles
what is the cause of pyomyositis
90% = staph
what is Synovitis Acne Pustolosis Hyperostosis Osteitis (SAPHO) known as in children
chronic recurrent multifocal osteomyelitis (CRMO)
what are the symptoms of SAPHO/CRMO
exacerbations and remissions
fever
weight loss
generalised malaise
what are the investigations of SAPHO/CRMO
samples = exclude osteomyelitis
raised inflammatory markers
X-ray = lytic lesions
what investigations should be done if an infected arthroplasty is suspected
CRP
joint aspiration
bone scan
X-ray
what is the history of an infected arthroplasty
problem with the wound
never been pain free
what is the treatment of an infected arthroplasty
two stage revision
what is tetanus
gram positive, anaerobic rods
what does tetanus release
neurotoxin which causes spastic paralysis due to binding to inhibitory neurones preventing the release of neurotransmitters
what is the incubation period of tetanus
4 days - several weeks
what are the symptoms of tetanus
lockjaw
muscle spasms
what is the treatment of tetanus
surgical debridement
anti-toxin
antibiotics
booster vaccination
what antibiotics are used in the treatment of tetanus
penicillin or metronidazole
