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−<big><center>[[Enterobacteriaceae|'''BACK TO ENTEROBACTERIACEAE''']]</center></big>+<big><center>[[Bacteria|'''BACK TO BACTERIA''']]</center></big>
−<big><center>[[Infectious agents and parasites|'''BACK TO INFECTIOUS AGENTS AND PARASITES''']]</center></big>
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+***Acute, frequently fatal enterotoxaemia of weaned pigs+
−***Associated with particular haemolytic serotypes of ''E. coli''
−***Verotoxin (Shiga toxin II e) released in the small intestine and carried in the bloodstream
−***Haemolysin production
−***Subcutaneous and subserosal oedema
−***Peracute disease affecting particulary healthy piglets
−***Mortality rate 30%-90%
−***Antimicrobial treatment effective if administered in time
===Intestinal infection===+
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{{review}}
−===''Eschericia coli'' (''E. coli'') overview===
===''Eschericia coli'' (''E. coli'') overview===
−[[File:Ecoli.jpg|200px|right]]
*Member of ''Enterobacteriacae'' family of Gram-negative bacilli
*Member of ''Enterobacteriacae'' family of Gram-negative bacilli
*'''Facultative anaerobe'''
*'''Facultative anaerobe'''
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*Capsular polysaccharides produced by some strains prevent phagocytosis and interfere with complement
*Capsular polysaccharides produced by some strains prevent phagocytosis and interfere with complement
*Endotoxin is a lipolysaccharide component of the cell wall of Gram-negative bacteria, composed of lipid A, a core polysaccharide and various side chains
*Endotoxin is a lipolysaccharide component of the cell wall of Gram-negative bacteria, composed of lipid A, a core polysaccharide and various side chains
−*'''Endotoxin''' is realeased when bacteria die, and causes endothelial damage leading to '''disseminated intravascular coagulation''' and e'''ndotoxic shock'''; it is also a '''pyrogen'''
+*'''Endotoxin''' is realeased when bacteria die, and causes endothelial damage leading to [[Disseminated Intravascular Coagulation|'''disseminated intravascular coagulation''']] and '''endotoxic shock'''; it is also a '''pyrogen'''
*Enterotoxins, verotoxins and cytotoxic necrotising factors produced by many pathogenic ''E. coli''; these produce cell damage at their site of action
*Enterotoxins, verotoxins and cytotoxic necrotising factors produced by many pathogenic ''E. coli''; these produce cell damage at their site of action
*'''Alpha-haemolysin''' may increase iron availability for invading organisms
*'''Alpha-haemolysin''' may increase iron availability for invading organisms
*'''Siderophores''' are made by certain pathogenic strains, and are responsible for iron aquisition; they include aerobactin and enterobactin
*'''Siderophores''' are made by certain pathogenic strains, and are responsible for iron aquisition; they include aerobactin and enterobactin
−==Extra-intestinal infection==
==Extra-intestinal infection==
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***Most common organism infecting urinary tract
***Most common organism infecting urinary tract
***Ascending infections of urinary tract
***Ascending infections of urinary tract
−***Causes pyometra in the dog and cat and [[Kidney - Tubulointerstitial disease#Pyelonephritis|pyelonephritis]]
+***Causes pyometra in the dog and cat and [[Pyelonephritis|pyelonephritis]]
***Cystitis in the bitch
***Cystitis in the bitch
***Prostatitis in dogs via opportunistic infection
***Prostatitis in dogs via opportunistic infection
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***Death within 24-48 hours during peracute disease
***Death within 24-48 hours during peracute disease
***Animals depressed with sunken eyes
***Animals depressed with sunken eyes
−**'''Avian [[Intestines - Catarrhal Enteritis#Colibacillosis|colibacillosis]]''':
+**[[Colibacillosis|'''Colibacillosis''']]:
−***Septicaemia in newly-hatched chickens
+***Avian:
−***Infection enters via faecal contamination of the egg surface or via the ovary of the hen
+****Septicaemia in newly-hatched chickens
−***Infection enters via the respiratory tract
+****Infection enters via faecal contamination of the egg surface or via the ovary of the hen
−***A bacteraemia develops
+****Infection enters via the respiratory tract
−***Acute colisepticaemia, subacute fibrinopurulent serositis or chronic granulomatous disease of the viscera
+****A bacteraemia develops
−***Occurs in older birds via inhalation of ''E. coli'' in dust; respiratory infection spreads to the blood to cause acute colisepticaemia
+****Acute colisepticaemia, subacute fibrinopurulent serositis or chronic granulomatous disease of the viscera
−***Airsacculitis, pericarditis and perihepatitis during acute phase
+****Occurs in older birds via inhalation of ''E. coli'' in dust; respiratory infection spreads to the blood to cause acute colisepticaemia
−***Often secondary to virus or mycoplasma infection or environmental stress
+****Airsacculitis, pericarditis and perihepatitis during acute phase
+****Often secondary to virus or [[:Category:Mycoplasmas|''mycoplasma'']] infection or environmental stress
**'''Colisepticaemia''':
**'''Colisepticaemia''':
***Systemic disease in young calves, piglets, foals, lambs
***Systemic disease in young calves, piglets, foals, lambs
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***Virulence related to adhesive properties, complement resistance and ability for iron aquisition
***Virulence related to adhesive properties, complement resistance and ability for iron aquisition
***Ammonia, dust, viral infections and temperature changes enhance likelihood of disease
***Ammonia, dust, viral infections and temperature changes enhance likelihood of disease
−**'''Oedema disease of pigs''':
+**[[Oedema Disease|'''Oedema disease of pigs''']]:
−**'''Watery mouth of lambs''':
**'''Watery mouth of lambs''':
***Affects lambs under three days old
***Affects lambs under three days old
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***Severe depression, anorexia, salivation and abdominal distension
***Severe depression, anorexia, salivation and abdominal distension
***Morbidity and mortality high
***Morbidity and mortality high
−** [[Intestines - Inflammatory Bowel Disease And Related Conditions#Histiocytic Ulcerative Colitis|Histiocytic ulcerative colitis]] in the dog and cat.
+** [[Inflammatory Bowel Disease#Histiocytic Ulcerative Colitis|Histiocytic ulcerative colitis]] in the dog and cat.
−** Causes [[Peritoneal cavity - inflammatory#In dogs|peritonitis in dogs]] and [[Peritoneal cavity - inflammatory#In pigs|peritonitis in pigs]]
+** Causes [[Peritonitis - Cats and Dogs|peritonitis in dogs]] and [[Peritonitis#In pigs|peritonitis in pigs]]
−**Found in [[Bones - inflammatory#Osteomyelitis|osteomyelitis]]
+**Found in [[Osteomyelitis|osteomyelitis]]
−**Associated with neonatal [[Joints - inflammatory#In Cattle|polyarthritis of calves]]
+**Associated with neonatal [[Infectious Arthritis#In Cattle|polyarthritis of calves]]
−**Found in [[Joints - inflammatory#In Horses|arthritis of horses]]
+**In [[Deep Pyoderma|deep pyoderma]]
+**Found in [[Infectious Arthritis#In Horses|arthritis of horses]]
−==Intestinal infection==
*''E. coli'' is part of the flora of the large intestine, but is not usually found in the small intestine
*''E. coli'' is part of the flora of the large intestine, but is not usually found in the small intestine
*Some strains possess fimbrae which attach the bacteria to the small intestinal epithelium of particular animal species
*Some strains possess fimbrae which attach the bacteria to the small intestinal epithelium of particular animal species
−*''E. coli'' may cause diarrhoea via attaching and effacing lesions, where bacteria adhere intimately to the enterocyte, and cause localised effacement of the brush border microvilli; the epithelial erosion causes dysentery
+*''E. coli'' may cause diarrhoea via attaching and effacing lesions, where bacteria adhere intimately to the enterocyte, and cause localised effacement of the brush border microvilli; the epithelial erosion causes [[Haemorrhage#Dysentery|dysentery]]
−*Enterotoxigenic ''E. coli'' (ETEC):
+*'''Enterotoxigenic ''E. coli'' (ETEC)''':
**General:
**General:
−*** Contributes to [[Intestines - Catarrhal Enteritis#Undifferentiated Neonatal Calf Diarrhoea|undifferentiated neonatal calf diarrhoea]], a mixed viral enteritis in calves, also known as enteric colibacillosis
+*** Contributes to [[Calf Diarrhoea, Undifferentiated Neonatal|undifferentiated neonatal calf diarrhoea]], a mixed viral enteritis in calves, also known as enteric colibacillosis
***Causes scours in pigs, calves and lambs
***Causes scours in pigs, calves and lambs
***'Traveller's diarrhoea' in humans
***'Traveller's diarrhoea' in humans
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***K88 (F4) is associated with adhesion to the small intestinal mucosa of pigs
***K88 (F4) is associated with adhesion to the small intestinal mucosa of pigs
***K99 (F5) associated with adhesion in pigs and cattle (these fimbrial adhesins were originally thought to be capsular (K) antigens)
***K99 (F5) associated with adhesion in pigs and cattle (these fimbrial adhesins were originally thought to be capsular (K) antigens)
−***The fimbriae are encoded by plasmids
+***The '''fimbriae are encoded by plasmids'''
***These strains carry a plasmid which encodes an enterotoxin
***These strains carry a plasmid which encodes an enterotoxin
−***Two types of enterotoxin: heat-labile (LT) and heat-stable (ST) toxins
+***Two types of '''enterotoxin: heat-labile (LT) and heat-stable (ST) toxins'''
−***The plasmids which produce these toxins are responsible for the pathogenicity of these strains
+***The '''plasmids''' which produce these toxins are '''responsible for the pathogenicity''' of these strains
−***LT is an oligometric toxin composed of an enzymatically-active A subunit (30KDa; 2 fragments - A1 and A2) and 5 identical B subunits (12KDa) forming the binding portion (B oligomer)
+****'''LT'''
−***It attaches to the brush border of the epithelial cells of the small intestine
+*****An oligometric toxin composed of an enzymatically-active A subunit (30KDa; 2 fragments - A1 and A2) and 5 identical B subunits (12KDa) forming the binding portion (B oligomer)
−***LT causes ADP-ribosylation of the stimulatory subunit of guanine nucleotide binding proteins of the adenylate cyclase complex in eukaryotic cell membranes
+*****It attaches to the brush border of the epithelial cells of the small intestine
−***This causes irreversible activation of adenylate cyclase in target cells
+*****Causes ADP-ribosylation of the stimulatory subunit of guanine nucleotide binding proteins of the adenylate cyclase complex in eukaryotic cell membranes
−***This raises the cAMP level and causes hypersecretion of water and chloride ions into the lumen of the small intestine and inhibits reabsorption of sodium
+*****This causes irreversible activation of adenylate cyclase in target cells
−***ST activates guanylate cyclase in enteric epithelial cells, stimulating fluid secretion
+*****This raises the cAMP level and causes hypersecretion of water and chloride ions into the lumen of the small intestine and inhibits reabsorption of sodium
+****'''ST'''
+*****Activates guanylate cyclase in enteric epithelial cells, stimulating fluid secretion
**Clinical signs:
**Clinical signs:
−***The gut becomes distended with fluid and a [[Intestines - diarrhoea#Secretory Diarrhoeas|secretory diarrhoea]] which lasts several days results
+***The gut becomes distended with fluid and a [[Diarrhoea#Secretory Diarrhoeas|secretory diarrhoea]] which lasts several days results
***Watery diarrhoea, dehydration, acidosis, death
***Watery diarrhoea, dehydration, acidosis, death
−**Immunuty:
+**Immunity:
***LT is antigenic
***LT is antigenic
***Immunity is developed via production of antibody to LT protein and fimbrial antigen
***Immunity is developed via production of antibody to LT protein and fimbrial antigen
***Parenteral vaccination of pigs and cattle protects offspring from scours via antibody production in the colostrum (passive immunity)
***Parenteral vaccination of pigs and cattle protects offspring from scours via antibody production in the colostrum (passive immunity)
***ST is not immunogenic; it is small, with only 19 amino acids
***ST is not immunogenic; it is small, with only 19 amino acids
−*Enteropathogenic ''E. coli'' (EPEC):
+**Attching and effacing strains of ''E. coli''
+*'''Enteropathogenic ''E. coli'' (EPEC)''':
+**Attaching and effacing strains of ''E. coli''
**Attach to small intestinal epithelial cells and cause necrosis of enterocytes and stunting and fusion of villi
**Attach to small intestinal epithelial cells and cause necrosis of enterocytes and stunting and fusion of villi
**Possess ''E. coli'' adherence factor plasmid
**Possess ''E. coli'' adherence factor plasmid
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**Intracellular calcium levels increase and production of protein kinase C causes loss of chloride ions and water from the intestinal epithelial cells
**Intracellular calcium levels increase and production of protein kinase C causes loss of chloride ions and water from the intestinal epithelial cells
**Diarrhoea results
**Diarrhoea results
−*Enteroinvasive ''E. coli'':
+*'''Enteroinvasive ''E. coli''''':
**Cause colisepticaemia in calves during their first week of life; occasionally in lambs, piglets and puppies
**Cause colisepticaemia in calves during their first week of life; occasionally in lambs, piglets and puppies
**Infection via ingestion or umbilicus; inadequate colostrum increases susceptibility
**Infection via ingestion or umbilicus; inadequate colostrum increases susceptibility
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**Abscesses, pneumonia in long term
**Abscesses, pneumonia in long term
**Death occurs in absense of treatment
**Death occurs in absense of treatment
−*Enterohaemorrhagic ''E. coli'':
+*'''Enterohaemorrhagic ''E. coli''''':
**Possibly carried by cattle
**Possibly carried by cattle
**Produce shiga-like toxin, a vero toxin
**Produce shiga-like toxin, a vero toxin
**Plasmid-coded fimbriae important for virulence
**Plasmid-coded fimbriae important for virulence
−**Intimin produced allowing intimate attchment to intestinal epithelial cells
+**Intimin produced allowing intimate attachment to intestinal epithelial cells
**Strains do not product LT or ST and are not enteroinvasive
**Strains do not product LT or ST and are not enteroinvasive
**Attaching and effacing lesions, unrelated to toxin production
**Attaching and effacing lesions, unrelated to toxin production
−**Disseminated intravascular coagulation and thrombus formation
+**[[Disseminated Intravascular Coagulation|Disseminated intravascular coagulation]] and thrombus formation
**''E. coli'' O157:H7 causes haemorrhagic collitis-haemolytic uraemic syndrome in humans
**''E. coli'' O157:H7 causes haemorrhagic collitis-haemolytic uraemic syndrome in humans
−*Cytotoxin necrotising factor-producing ''E. coli''
+*'''Cytotoxin necrotising factor-producing ''E. coli'''''
**Infrequently cause diarrhoea in calves, pigs and humans
**Infrequently cause diarrhoea in calves, pigs and humans
**Important virulence factors include toxin and fimbriae
**Important virulence factors include toxin and fimbriae
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+==in cattle==
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+
+*Neonatal polyarthritis:
+
+**[[Escherichia coli|'''''Coliforms''''']]
+***Localises in joints and meninges in severe non-fatal neonatal colibacillosis
+***May remain as chronic arthritis in larger joints
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+[[Category:Enterobacteriaceae]]
+[[Category:To_Do_-_Bacteria]]