Septic arthritis

Question 1

Define septic arthiritis

Answer 1

defined as infection of 1 or more joint by pathogenic innoculation

can be heamatogenous spread of direct innoculation

treat any joint swelling as septic arthritis until proven otherwise-dint want to miss it

Question 2

Aetiology and risk factors of septic arthiritis

Answer 2

can come via blood or direct innoculation
most common causative organisms are staph and strep (91%)
sexually active-gonnorhoa
the older the patient, the more likely gram-

can be any joints-most commonly Large joints (knee, hips), and single joints

risk factors
Pre-exisitng joint disease (RA/OA)
Joint prostheses (10x)
IV drug use
Immunosupressed/HIV
diabetes
Steroids injections
surgery

Question 3

Epidiemology of septic arthiritis

Answer 3

about 6 in 100 000

10x more in prosthesis

Question 4

Signs and Sx of septic arthiritis

Answer 4

Hot, swollen, painful and restricted joint-similar to gout
Hx < 2 weeks-acute
Fever

Knee, hips, shoulders, ankle, elbow (in order)-but assume all single joint swelling to be septic arthiritis

Question 5

Investigations of septic arthiritis

Answer 5

Synovial fluid aspirates, microbiology and culture-gold standard
Synovial WCC-raised

the colour, viscosity and clarity are a big clue

WCC,ESR,CRP-raised

xray-degenerative changes of the joint-the borders

always see signs of sepsis–