Lecture 10 Flashcards
What is the bio containment level for Actinomycetales?
level 1-2
Are Actinomycetales gram positive or negative?
Positive
What is the appearance of Actinomycetales, Nocardia?
Filamentous rods
Describe the appearance of Trueperella pyogenes
Pleomorphic gram positive croci-rods
Describe the appearance of Dermatophilus congolensis
Branching filaments
Fragment into packets of coccoid cells
Tram tract appearance*
Where is streptomyces found?
Soil
Usually non-pathogenic
Where is actinomyces found on the host? (3)
Mucous membranes
Nasal cavity
Pharynx
Where is Trueperella found on the host? (3)
Mucous membranes
Nasal cavity
Pharynx
Where is Dermatophilus congolensis found?
Maintained by carrier animals
Where is Nocardia found?
Envr organism
What are the virulence factors for Trueperella pyogenes? (4)
Pyolysin - cytotoxic
Neuraminidases, collagen binding PROs & fimbriae - for adhesion
What are the virulence factors for Dermatophilus congolensis?
Protesases - tissue breakdown
Describe the sulfur granules from Actinomyces
Centrally located bacteria surrounded by clouds of eosinophilic material
What disease does Acintomyces bovis cause in cattle?
Lumpy jaw
Describe the pathogenesis of lumpy jaw caused by Actinomyces bovis
A. bovis is a normal oral microbiota
Course feed (ex: plant awns) cause lesions in the oral cavity (usually the mandible)
A. bovis will invade
New periosteal bone will form in response to infection
Fibrosis occurs
Forms a hard & immovable painless mass, draining tracts may develop
Usually the mass is painful unless it involves the teeth
How do you tx lumpy jaw caused by Actinomyces bovis?
Debridement & penicillin
May need to drain, if so consult surgeon
What is the px of lumpy jaw caused by Actinomyces bovis?
Tx may arrest growth of lesion, but regression is usually minimal (new bone formation is permanent)
What is the management to prevent lumpy jaw caused by Actinomyces bovis?
Allow access to high quality feed
How does Actinomyces spp normally present in dogs & Cats?
As a pyothorax
Describe the pathogenesis of Actinomyces infection in dogs & cats
Normal member of microbiota
When there is some sort of injury to the oropharynx (bite wound, grass awns, FBs etc.) then the bacteria enter the wound
Normally presents as a pyothorax
Pulmonary infections can occur when they aspirate the awn
&
Abdominal infections can occur following ingestion & migration of the awn out of the GIT into the abdomen
What are the symptoms of a dog or cat with Actinomyces?
Variable
May have firm or fluctuant lesions
May have draining tracts
Head & cervical region most commonly effected
What do the lesions contain in a dog or cat with Actinomyces infection?
Serosanguinous to purulent material
Contain sulfur granules