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<big><center>[[Infectious agents and parasites|'''BACK TO INFECTIOUS AGENTS AND PARASITES''']]</center></big>
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#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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*Samples include pus, exudate, affected tissues and urine
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*Presence of coryneform organisms in smears
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*Culture on blood agar, selective blood agar and MacConkey agar
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*Do not grow on MacConkey
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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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