MSK microbiology Flashcards
what is septic arthritis?
infection of joint space
what is septic arthritis caused by?
MSSA, strep
rare - h. influenza, neuseria gonorrhoea
how is septic arthritis spread
blood. contagious. direct
what investigations should be done in suspected septic arthritis
blood culture if fever CRP, FBC, U&Es, lactate etc joint fluid washout for culture, microscopy - crystals, WCC, gram stain US x-ray MRI bone scan CT
what are the symptoms of septic arthritis
acute monoarrhtropathy (inflammation on one joint at a time) decreased movement, swelling, systemic upset, increased WCC, increased inflam markers
what is osteomyelitis and where does it occur
inflammation/infection of bone and medullary cavity
long bone, vertebrae
may reoccur if treatment suboptimal
what are the causes of osteomyelitis
acute - mssa, strep
chronic - tb, psuedomonaks aeruginosa, salmonella esp in sickle cell patients, brucella - goats/cows milk, coliforms
how is osteomyelitis spread
blood, contiguous, PVD associated, prosthetic valve associated
what is the treatment of septic arthritis
if SA - flucoxacilllin high dose (IV)
in under 5 add ceftriaxone for HI and kingella cover
change when blood cultures come out
2-4 weeks
acute osteomyelitis - how long does it last for, what do infants have more of a risk of, what spread and where
few days to 2 weeks
infants are more at risk of septic arthritis
blood spread more likely
femur, tibia, shoulder, able, hip, elbow
chronic osteomyelitis - why, how long, treatment
if acute is not treated may progress
over 2 wks
is SIRS absent (usually is) then no need for immediate antibiotic treatment - wait till cultures
investigations for osteomyelitis
blood culture if fever
bony biopsy/wahsout
treatment of osteomyelitis
high flucox
modify w culture results
4-8 weeks of antibiotics
PJI risk factors
rheumatoid, diabetes, malnutrition, obesity
PJI 0-3 months is called what, symptoms and causes
early post op
fever, effusion, warmth drainage
SA, strep, enterococci
