Difference between revisions of "Category:Actinomycetes"

From WikiVet English
Jump to navigation Jump to search
 
(11 intermediate revisions by 2 users not shown)
Line 1: Line 1:
===Overview===
+
{{frontpage
 +
|pagetitle =Actinomycetes
 +
|pagebody = Actinomycetes organisms are gram positive bacteria that grow slowly on media and produce branching filaments. They are associated with opportunistic infections causing inflammatory responses and granulomatous reactions; animal pathogens include ''Actinomyces, Arcanobacterium, Actinobaculum, Nocardia'' and ''Dermatophilus''.
  
*Gram positive bacteria  
+
Actinomycetes organisms are non-motile, non-spore-forming bacteria which are anaerobic or facultative anaerobes that typically colonise mucous membranes. They will grow on enriched media and are non-acid fast, Modified Ziehl-Neelson negative when stained.
*Grow slowly on media and produce branching filaments
+
Clinically, this class of organisms includes ''Micropolyspora faeni and Thermactinomyces vulgaris'' - these are implicated in [[Extrinsic Allergic Bronchio-Alveolitis|Bovine Farmers Lung]] and ''Thermactinomyces vulgaris'' is associated with the pathology of [[Recurrent Airway Obstruction|RAO]] in horses.
*Opportunistic infections causing inflammatory responses and granulomatous reactions
 
*Animal pathogens include ''Actinomyces, Arcanobacterium, Actinobaculum, Nocardia'' and ''Dermatophilus''
 
  
===''Arcanobacterium, Actinomyces'' and ''Actinobaculum'' species===
+
|contenttitle =Content
 +
|contentbody =<big><b>
 +
<categorytree mode=pages>Actinomycetes</categorytree>
 +
</b></big>
 +
|logo =bugs-logo copy.png
 +
}}
  
*Non-motile, non-spore-forming bacteria
+
[[Category:Bacterial Organisms]]
*Anaerobic or facultative anaerobes
+
[[Category:Gram_positive_bacteria]]
*Grow on enriched media; non-acid fast
 
*Colonise mucous membranes
 
*Modified Ziehl-Neelson negative
 
 
 
 
 
<big>'''''<ncl style=compact maxdepth=2 headings=bullet headstart=2 showcats=1 showarts=1>Category:{{PAGENAME}}</ncl></big>
 
''[[Arcanobacterium pyogenes]]''
 
 
 
''[[:Category:Actinomyces|Actinomyces]]''
 
 
 
 
 
===''[[Actinobaculum suis]]''===
 
 
 
===''[[:Category:Nocardia|Nocardia]]''===
 
 
 
 
 
 
 
 
 
===''Dermatophilus congolensis''===
 
 
 
*Filamentous, branching actinomycete
 
*Aerobic
 
*Produces motile zoospores
 
*No growth on Sabouraud dextrose agar
 
*Dermatophilosis most prevalent in tropical and subtropical regions
 
*Organisms found in scabs and in foci in skin of carrier animals
 
*Dormant zoospores become activated when moisture and temperature levels are favourable
 
*Zoospores may survive 3 years in scabs
 
*'''Pathogenicity''':
 
**Does not usually invade healthy skin
 
**Entrance after trauma or persistent wetting
 
**Activated zoospores produce germ tubes which develop into filaments which invade the epidermis
 
**Invasion causes an accute inflammatory response with many [[Neutrophils - WikiBlood|neutrophils]]
 
**Microabscesses are formed in the skin
 
**Raised crusts develop in the affected regions
 
*[[Bacterial skin infections - Pathology#Dermatophilosis|'''Pathology''']]
 
*'''Diagnosis''':
 
**Giemsa-stained smears from scabs reveal branching filaments containing zoospores
 
**Immunofluorescence
 
**Scab material can be cultured on blood agar at 37 degrees centigrade, 2.5-10% carbon dioxide for 5 days
 
**Zoospores can be cultured
 
**After incubation, colonies are yellow and haemolytic (after 48 hours); they later become rough and yellow, and gain a mucoid appearance
 
**No growth on Sabouraud dectrose agar
 
*'''Clinical infections''':
 
**Infection usually confined to epidermis
 
**Dermatophilosis
 
**Disease most prevalent in young animals
 
**Damage to the skin predisposes to infection; blood-sucking insects also thought to be involved in transmission
 
**Lesions after heavy rainfall predominantly affect dorsum of farm animals
 
**Papules, serous, exudative matting of hair, raised crusty scabs
 
**Scab formation more prominent in sheep and cattle than in horses
 
**Lesions may resolve within weeks if dry weather, or may progress
 
*'''Treatment''':
 
**Parenteral antibiotics e.g oxytetracycline, pr penicillin-streptomycin combinations
 
 
 
 
 
*''Micropolyspora faeni and Thermactinomyces vulgaris'' in [[Bronchi and Bronchioles Inflammatory - Pathology#Extrinsic Allergic Bronchio-alveolitis|Bovine Farmers Lung]]
 
*''Thermactinomyces vulgaris'' may cause [[Bronchi and Bronchioles Inflammatory - Pathology#Chronic obstructive pulmonary disease (COPD)|COPD]]
 
[[Category:Bacteria]]
 

Latest revision as of 16:19, 19 February 2011

Actinomycetes

Actinomycetes organisms are gram positive bacteria that grow slowly on media and produce branching filaments. They are associated with opportunistic infections causing inflammatory responses and granulomatous reactions; animal pathogens include Actinomyces, Arcanobacterium, Actinobaculum, Nocardia and Dermatophilus.

Actinomycetes organisms are non-motile, non-spore-forming bacteria which are anaerobic or facultative anaerobes that typically colonise mucous membranes. They will grow on enriched media and are non-acid fast, Modified Ziehl-Neelson negative when stained.

Clinically, this class of organisms includes Micropolyspora faeni and Thermactinomyces vulgaris - these are implicated in Bovine Farmers Lung and Thermactinomyces vulgaris is associated with the pathology of RAO in horses.

Subcategories

This category has the following 2 subcategories, out of 2 total.

A

N

Pages in category "Actinomycetes"

The following 5 pages are in this category, out of 5 total.