| Summary Information |
| Diseases / List of Bacterial Diseases
/ Disease summary |
| Alternative Names |
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| Disease Agents |
- Various bacteria, particularly Pseudomonas spp. (B602.35.w35)
also Pasteurella multocida.
(B600.16.w16)
- Following either traumatic injury or surgery, associated with
avascularity of bone, contamination of the wound (more than 105
organisms per gram tissue) and a suitable environment - e.g. a
haematoma. (B602.35.w35)
- Dental disease, particularly periapical abscesses. (B600.8.w8)
- Malnourishment can exacerbate abscessation. (B600.8.w8)
- Secondary to Ulcerative Pododermatitis in Lagomorphs.
(B600.9.w9)
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| Infectious
Agent(s) |
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| Non-infectious
Agent(s) |
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| Physical
Agent(s) |
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| General Description |
Clinical signs
- In a rabbit following fracture repair: fluctuant swelling of
the foot, inability to bear weight on the affected foot. On incision
of the swelling, thick, partially inspissated pus was released. The
fracture failed to heal despite wound flushing and appropriate systemic antibiotics. (J4.185.w7)
- Mandibular swelling, bony. (J196.70.w1)
(B602.35.w35)
Pathological findings
Gross pathology
- Affected mandible grossly and irregularly enlarged, containing a 2.5
cm diameter well-circumscribed holly bony mass, the inner wall of
which was lined with inspissated pus, and a fistulous tract through
the bone. (J196.70.w1)
Histopathology
- In a rabbit following fracture repair:
- Fracture site abscessation, extending into the medullary cavity
of the affected metatarsal, with little overlying cellulitis. (J4.185.w7)
- In a rabbit with mandibular osteomyelitis: hollow bony mass
with a fibrous capsular wall, acute and chronic inflammatory cells and
inner degenerative heterophils. Numerous irregular exostoses with
degenerative (lytic) changes. Throughout the affected mandible,
fibrosis and inflammatory cell infiltration. (J196.70.w1)
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| Further Information |
Susceptibility
- Open fractures are more likely to develop infection leading to
osteoarthritis in rabbits than in most other species. (B601.17.w17,
B602.35.w35)
- Compromised blood supply to the bone increases the risk of
infection. (B602.35.w35,
J4.185.w7)
Transmission
- Infection may be from gross contamination or blood-borne spread from
another site of infection in the rabbit. (B602.35.w35,
J4.185.w7)
Diagnosis
- Clinical signs.
- Radiographic findings.
- In osteomyelitis of the mandible, bony proliferation around
central osteolytic areas. (J196.70.w1)
- Periosteal reaction and osteolysis; sometimes an involucrum. (B602.35.w35)
- Radiography is important to show the extent of bone (and joint)
involvement and destruction. (B600.8.w8)
- The prognosis is poor if osteomyelitis affects more than one
limb. (B600.8.w8)
- Culture of pus and sensitivity testing is required. (J4.185.w7)
- Send samples for both aerobic and anaerobic culture. (B602.35.w35)
- Differential diagnosis for dental-related facial osteomyelitis
swellings includes neoplasia. (B600.8.w8)
Treatment
- Aggressive treatment is required; treatment of
osteomyelitis in rabbits appears to be more difficult than in most
other species and is not always successful. (B601.17.w17,
B602.35.w35, N12.38.w1)
- Surgical drainage and debridement followed by appropriate antibiotic
treatment. (B602.35.w35,
J196.70.w1)
- Infected bone and any foreign bodies (including elongated tooth
crowns, if these are penetrating tissue) must be removed, as well
as infected tooth roots in osteomyelitis associated with apical
abscesses. (B600.8.w8)
- All sinuses and tracts must be thoroughly explored to detect
deeper connecting abscesses. (B600.8.w8)
- Antibiotic treatment should be based on culture and sensitivity,
using an antibiotic which is effective against the causal agent
and reaches therapeutic levels in the affected tissues. (B600.8.w8)
- Antibiotic-impregnated beads, containing appropriate
antibiotics at appropriate concentrations, may be implanted under sterile conditions. (B602.35.w35)
- This provides a high concentration of antibiotic at the
required site. (B600.8.w8)
- As an added advantage, some owners may find the stitched-up wound
more aesthetically pleasing than an open cavity which is
receiving topical treatment. (B600.8.w8)
- Note: care is required. If the abscess capsule is not
intact (i.e. the abscess is not fully walled off), there may
be leakage of antibiotic into the surrounding tissues and
thereby the systemic circulation. If this occurs, the usual
considerations apply regarding possible effects of antibiotics
on the rabbit's gut flora. (V.w65)
- Repeated surgery may be required. (N12.38.w1)
- Amputation may be an option if extensive bone destruction affects
one limb only. (B600.8.w8)
- Note: following amputation, there is an increased risk of
development of ulcerative pododermatitis in the remaining limbs,
due to increased pressure. (B600.8.w8)
- Improve general health by good husbandry including a good diet,
companionship, comfortable bedding and appropriate exercise
opportunities. (B600.8.w8)
Prevention
- Ensure strict sterile technique during orthopaedic surgery, as well
as careful tissue handling, good haemostasis and good anatomical
closure. (B602.35.w35)
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| Associated Techniques |
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| Host taxa groups /species |
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| Disease Author |
Dr Debra Bourne MA VetMB PhD MRCVS
(V.w5) |
| Referees |
John Chitty BVetMed CertZooMed MRCVS
(V.w65) |