Difference between revisions of "Category:Campylobacter species"

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[[Campylobacter jejuni]]
  
  
===[[Intestine Pathogens - Pathology#Campylobacter jejuni|''Campylobacter jejuni'']]===
 
 
*Widespread on farms - hyperendemic
 
*Carried as commensals in intestines of cattle, sheep, dogs, wild birds and especially chickens
 
*Farm animals regularly exposed via faecal-oral route; maternal antibody protects while active immunity develops
 
*Animals with little exposure are very susceptible, e.g. humans, pets
 
*Most chicken carcasses contaminated, leading to food poisoning and enterocolitis in people from uncooked meat
 
*Colonisation, attachment and invasion of colonic enterocytes; toxin production
 
*Necrosis of colonic absorptive epithelial cells, erosion of mucosa, crypt abscesses, inflammatory infiltrate of [[Neutrophils - WikiBlood|neutrophils]] into mucosa causes colitis
 
*Enteritis and diarrhoea in susceptible dogs; treatment with enrofloxacin
 
*Causes abortion in ewes
 
*Usually asymptomatic infections in chickens and turkeys, but occasional outbreaks of avian hepatitis occur with decreased egg production, loss of condition, haemorrhage and necrosis of liver; phase contrast microscopy demonstrates curved rods in bile; in-feed dihydrostreptomycin sulphate in outbreak
 
*Implicated in [[Intestines Catarrhal Enteritis - Pathology#Undifferentiated Neonatal Calf Diarrhoea|undifferentiated neonatal calf diarrhoea]], a mixed viral enteritis in calves
 
 
[[Category:Bacteria]][[Category:Gram_negative_bacteria]]
 
[[Category:Bacteria]][[Category:Gram_negative_bacteria]]

Revision as of 21:32, 10 May 2010

Overview

  • Live on mucosa of intestinal and genital tract and can be commensals or pathogens
  • Enteric species cause disease in humans
  • Other species cause infertility and abortion in cattle and sheep
  • Excreted in faeces of birds, (C. jejuni and C. lari) as well as pigs contaminating water and food supplies
  • C. fetus restricted to bovine prepucial mucosa


Characteristics

  • Curved, Gram negative rods
  • Polar flagellum aids motility
  • Daughter cells remain joined giving gull-wing or spiral appearance
  • Microaerophilic
  • Sensitive to drying
  • Thermophilic species - C. jejuni, C. coli
  • Non-thermophilic species e.g. C. fetus
  • Grow on enriched selective media e.g. Skirrow agar in 1-10% carbon dioxide and 5-10% oxygen tension
  • C. jejuni requires increased temperatures for growth
  • Many grow on MacConkey
  • Oxidase positive, non-fermentative
  • C. fetus subspecies venerealis and subspecies fetus have small, round, smooth, translucent colonies
  • C. jejuni has small, flat, grey colonies with watery appearance
  • Smears stained with dilute carbol fuschin for 4 minutes


Pathogenesis and pathogenicity

  • C. fetus subspecies fetus and subspecies venerealis possess a microcapsule (S layer) which resists phagocytosis and serum-mediated destruction and enhances survival in the genital tract
  • Antigens of S layer undergoes antigenic shifts in C. fetus subspecies venerealis, allowing persistence in the host
  • C. jejuni attaches and invades host enterocytes and produces enterotoxin-like substances
  • Flagellae of C. jejuni required for colonisation


Campylobacter fetus subspecies venerealis


Campylobacter fetus subspecies fetus


Campylobacter jejuni

Pages in category "Campylobacter species"

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