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Flashcards in Infection Deck (12):
1

What is Newman's classification of septic arthritis?

A = pathogen isolated from joint
B = pathogen isolated from blood in context of a red, hot joint
C = no pathogen isolated but presence of histiological/radiological evidence of infection OR turbid fluid aspirated from joint
D = post-mortem isolation of pathogen

2

Give some risks for septic arthritis.

- RA
- OA
- immunocompromised
- iatrogenic trauma
- trauma
- joint prostheses
- IVDU
- alcoholism
- cutaneous ulcers

3

What is the aetiology of septic arthritis?

4-10/100,000p-y

Most common organism = Staph. aureus

Sickle-cell anaemia = Salmonella spp.

4

What investigations are needed in septic arthritis?

BLOODS:
- ESR/CRP
- WCCs
- blood culture
- U&Es
- LFTs
- serum procalcitonin

BIOPSY:
- joint fluid aspirate for Gram staining

IMAGING:
- radiographs
- Tch bone scan
- CT
- MRI

5

What is the management of septic arthritis?

Admit for supportive care
IV Abx = flucloxacillin/gentamicin + clindomycin
Aspirate fluid +/- washout

6

What are the Kocher criteria?

Differentiate septic arthritis from transient synovitis in children

Non-weightbearing on affected side = +1
ESR>40 = +1
Temp>38.5 = +1
WCCs > 12,000 = +1

1 = 3% likelihood of septic arthritis
2 = 40%
3 = 93%
4 = 99%

7

What is osteomyelitis?

Progressive inflammatory destruction due to bone infection

- most commonly Staph. aureus
- joint prosthesis infection forms biofilm
- extent: superficial (one cortex involved) to localised (one cortex + medulla) to diffuse/segmented (two cortices + medulla)

O/E:
- pain
- fever
- erythema
- tenderness
- oedema
- chronic limp
- sinus

8

What is the aetiology of chronic fasciitis?

- diabetes
- immunocompromised
- alcoholism
- peripheral vascular disease
- trauma

9

What is Fournier's gangrene?

Necrotising fasciitis/gangrene usually affecting the perineum

10

What is a Brodie's abscess?

Type of subacute osteomyelitis which may persist for years before converting to a frank osteomyelitis.

Abscess is moving away from epiphysis, therefore not affecting growth

Contained to localised area and walled off by fibrous granulation tissue

11

What is the most common organism implicated in dog bites?

Pasturella multocida

12

What are the BAPRAS guidelines for Abx cover for leg fractures?

Within 3hrs of injury give 1.2g of co-amoxiclav OR cefuroxime 1.5g 8hrly OR clindomycin 600mg 6hrly in penicillin allergy