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| − | <big><center>[[Infectious agents and parasites|'''BACK TO INFECTIOUS AGENTS AND PARASITES''']]</center></big>
| + | #REDIRECT[[:Category:Corynebacterium species]] |
| − | <big><center>[[Bacteria|'''BACK TO BACTERIA''']]</center></big>
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| − | *''C. pyogenes'' in [[Joints - inflammatory#In Sheep|arthritis]] of sheep post-dipping joint infection and [[Joints - inflammatory#In Pigs|arthritis in pigs]] and [[Joints - inflammatory#In Cattle|arthritis in cattle]]
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| − | *''Corynebacterium pseudotuberculosis'' may cause [[Muscles - inflammatory#Abscesses|myositis]]
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| − | *''Corynebacterium pseudotuberculosis'' in [[Bacterial skin infections#Deep pyoderma|deep pyoderma]]
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| − | ===Overview===
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| − | *Common inhabitants of skin and mucous membranes of animals
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| − | *Opportunistic infections
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| − | *Cause pyogenic infections
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| − | *Most species host specific
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| − | ===Characteristics===
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| − | *Small, tough, Gram positive rods
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| − | *Pleomorphic
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| − | *Cluster together to resemble Chinese characters - coryneform morphology
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| − | *Known as diphtheroids
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| − | *Catalase positive, oxidase negative
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| − | *Facultative anaerobes
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| − | *Require enriched media for growth
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| − | *Non-motile
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| − | ===Pathogenesis and pathogenicity===
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| − | *Pyogenic causing suppurative infections except for ''C. bovis''
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| − | *''C. bovis'' causes mild neutrophil response in teat canal of healthy dairy cows and may protect from more pathogenic bacteria
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| − | *''C. pseudotuberculosis'':
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| − | **Facultative intracellular pathogen inside macrophages
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| − | **Cell wall lipid
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| − | **Produces a phospholipase toxin which hydolyses sphingomyelin in mammalian cell membranes
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| − | **Phospholipase may enhance survival and multiplication in host in early stages
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| − | *''C. renale''
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| − | **Urinary tract pathogens
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| − | **Produce urease and hydrolyse urea
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| − | **Possess fimbriae for attachment to urogenital mucosa
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| − | **Infection when immunity reduced or following tissue damage during parturition
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| − | ===Clinical infections===
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| − | *Infection follows tissue trauma
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| − | *''C. pseudotuberculosis'' casues caseous lymphadenitis in sheep
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| − | *Carried on skin of sheep
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| − | *Infection through shearing wounds
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| − | *Ulcerative lymphangitis in horses
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| − | ===Diagnosis===
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| − | *Colony characteristics:
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| − | **''C. bovis'': lipophilic bacterium; small, white, dry, non-haemolytic colonies on plates inoculated with bovine milk
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| − | **''C. kutscheri'': white colonies; occasionally haemolytic
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| − | **''C. pseudotuberculosis'': small, white coloniess surrounded by narrow zone of complete haemolysis; colonies become dry and cream-coloured
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| − | **''C. renale'': small, non-haemolytic colonies after 24 hours; pigment produced after 48 hours
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| − | *Biochemical reactions:
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| − | **Certain strains of ''C. pseudotuberculosis'' reduce nitrates
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| − | **All pathogenic strains except ''C. bovis'' produce urease
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| − | *Enhancement of haemolysis produced by ''C. pseudotuberculosis'' when inoculated across a streak of ''Rhodococcus equi''
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