|
|
| (46 intermediate revisions by 6 users not shown) |
| Line 1: |
Line 1: |
| − | <big><center>[[Infectious agents and parasites|'''BACK TO INFECTIOUS AGENTS AND PARASITES''']]</center></big>
| + | #REDIRECT[[:Category:Clostridium species]] |
| − | <big><center>[[Bacteria|'''BACK TO BACTERIA''']]</center></big>
| |
| − | | |
| − | ===Overview===
| |
| − | | |
| − | *Organisms present in the soil, alimentary tract and faeces
| |
| − | *Endospores may be present in liver and may be reactivated to cause disease
| |
| − | *Neurotoxic clostridia, ''Clostridium tetani'' and ''Clostridium botulinum'' affect neuromuscular function but cause no tissue damage
| |
| − | *Histotoxic clostridia cause localised lesions in tissues and may cause toxaemia
| |
| − | *''C. perfringens'' cause inflammatory lesions in the gastrointestinal tract and enterotoxaemia
| |
| − | | |
| − | ===Characteristics===
| |
| − | | |
| − | *Large Gram-positive rods
| |
| − | *Obligate anaerobes
| |
| − | *Fermentative, catalase negative, oxidase negative
| |
| − | *Straight or slightly curved
| |
| − | *Motile by flagellae
| |
| − | *Require enriched media for growth
| |
| − | *Produce endospores which vary in shape and location and cause bulging of mother cell
| |
| − | | |
| − | | |
| − | ===Pathogenesis and pathogenicity===
| |
| − | | |
| − | | |
| − | | |
| − | | |
| − | ===Clostridium botulinum===
| |
| − | | |
| − | * ''Clostridium botulinum'' has been implicated in [[Intestines - physical disturbances#Equine dysautonomia, or grass sickness|equine grass sickness]].
| |
| − | * The toxin also causes [[Muscles - degenerative#Botulism|botulism]], a disease affecting muscle at the neuromuscular junction.
| |
| − | | |
| − | ===Clostridium chauvei===
| |
| − | | |
| − | * Causes [[General Pathology - Necrosis#Gas Gangrene|gas gangrene]], along with [[Clostridium species#Clostridium septicum|''Clostridium septicum'']].
| |
| − | * Infects muscles giving black leg [[Muscles - inflammatory#Black leg|myositis]]
| |
| − | | |
| − | ===Clostridium novyi===
| |
| − | | |
| − | * Causes [[General Pathology - Necrosis#Gas Gangrene|gas gangrene]] and [[Muscles - inflammatory#Gas gangrene|myositis]].
| |
| − | *May be involved in [[Bacterial skin infections#Systemic bacterial infections|cutaneous lesions]]
| |
| − | | |
| − | ===Clostridium perfringens===
| |
| − | | |
| − | * Causes:
| |
| − | ** [[Intestines - Fibrinous/ Haemorrhagic Enteritis#Lamb Dysentery (Enterotoxaemia with Blood)|Lamb dysentery]]
| |
| − | ** [[Intestines - Fibrinous/ Haemorrhagic Enteritis#Colitis X|Colitis X]].
| |
| − | ** [[Intestines - Catarrhal Enteritis#"Pulpy Kidney" Disease|Pulpy kidney disease]]
| |
| − | *** ''C. perfringens'' type D only.
| |
| − | ** [[Peritoneal cavity - inflammatory#In cattle|Peritonitis in cattle]]
| |
| − | ** [[Respiratory system - clinical signs#Dysphagia|Dysphagia in horses]]
| |
| − | ** [[General Pathology - Necrosis#Gas Gangrene|Gas gangrene]]
| |
| − | ** [[Muscles - inflammatory#Gas gangrene|Myositis]]
| |
| − | | |
| − | ===Clostridium septicum===
| |
| − | | |
| − | * Causes [[General Pathology - Necrosis#Gas Gangrene|gas gangrene]] and [[Muscles - inflammatory#Gas gangrene|myositis]]
| |
| − | | |
| − | ===Clostridium sordelli===
| |
| − | | |
| − | * Causes [[General Pathology - Necrosis#Gas Gangrene|gas gangrene]] and [[Muscles - inflammatory#Gas gangrene|myositis]]
| |
| − | | |
| − | ===Clostridium tetani===
| |
| − | | |
| − | * ''Clostridium tetani'' may infect wounds, giving rise to [[Tremors and Movement Disorders - Nervous System#Tetanus|tetanus]]
| |
| − | | |
| − | ===Diagnosis===
| |
| − | | |
| − | *Anaerobic transport medium
| |
| − | *Culture on blood agar enriched with yeast extract, vitamin K and haemin
| |
| − | *Anaerobic culture with hydrogen supplement and 5-10% carbon dioxide
| |
| − | *''C. perfringens'' colonies are surrounded by a zone of double haemolysis
| |
| − | *Biochemical tests
| |
| − | *Toxins identified in body fluids by toxin neutralisation or protection tests in lab animals
| |
| − | *Fluorescent antibody tests for histotoxic clostridia
| |
| − | *ELISA, PCR for toxin detection
| |