Septic arthritis Flashcards
1
Q
Common cause of infection
A
- Perforating injury
- Intra-articular injection
- post-operative infection of joint/tissues
2
Q
Common etiology traumatic infections
A
enteric bacteria
3
Q
Common etiology of iatrogenic infections
A
Staphylococcus aureus
4
Q
Septic arthritis
A
- Acute
- purulent exudate
- rapid destruction articular cartilage
- lysosomal enzymes released by neutraphils
5
Q
Modes of joint infections
A
- Primary: direct penetration
- Secondary: extension of infection from adjacent tissues into joint
- Tertiary: Hematogenous from other infected area
6
Q
Young animals
A
- 1 or more joints involved
- usually hematogenous
7
Q
Older animal
A
- Usually only 1 joint
- Usually from direct penetration or extension from adjacent infection
8
Q
Clinical signs
A
- Extreme pain, ush not weightbearing
- Heat and swelling around infected joint
- Fluid distention and edema
- Foals may present with septicemia
- Septic arthritis may be discovered during foal exam
- Animal may be depressed, off feed, sweating, febrile
9
Q
Classification of hematogenous septic arthritis/osteomyelitis in foals
A
S type: synovial
E type: epiphyseal - worst prognosis
P type: physeal
10
Q
S type infection
A
- Confined to joint space
- No evidence of osteomyelitis
11
Q
E type
A
- Infection begins in subchondral bone of epiphysis
- May extend through articular cartilage into joint
- Worst prognosis because of collapse of unsupported articular cartilage
12
Q
P type
A
Infection begins near physis
-from metaphyseal side
13
Q
Radiographic signs
A
- Early-soft tissue swelling, increase in joint space if limb weighbearing
- Late-narrowing of joint space, lysis subchondral bone, periosteal proliferation
14
Q
Diagnosis
A
- PE
- CBC/CHem
- adult horses: hyperfibrinogenemia, +/- high/normal WBC
- Foal: moderate leukocytosis, neutrophilia, hyperfibrinogenemia, blood culture
15
Q
Clin path joint fluid
A
- yellow/grey/blood tinged/cloudy/fibrin/pus
- 20,000-200,000 leukocytes/mm3; > 90% neuts
- Low pH (normal is 7.3)
