Campylobacter jejuni
From Wikipedia, the free encyclopedia
Campylobacter jejuni |
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Scanning electron micrograph of C. jejuni demonstrating the chracteristic curved rod shape of the organism.
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Scientific classification | ||||||||||||||
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Campylobacter jejuni (Jones et al. 1931) Veron & Chatelain 1973 |
Campylobacter jejuni is a species of curved, rod-shaped, gram negative bacteria commonly found in animal feces. It is one of the most common causes of human diarrhea in the world. Food poisoning caused by Campylobacter species can be severely debilitating but is rarely life-threatening. It has been linked with subsequent development of the neurodegenerative disease Guillain-Barré syndrome (GBS), which usually develops two to three weeks after the initial illness.
C. jejuni is commonly associated with chickens and has been found in wombat and kangaroo feces, being a cause of bushwalkers' diarrhea. It also naturally colonises many bird species. Contaminated drinking water and unpasteurized milk provide an efficient means for distribution. Contaminated food is a major source of isolated infections, with incorrectly prepared meat and poultry normally the source of the bacteria.
Infection with C. jejuni usually results in enteritis, which is characterised by abdominal pain, diarrhea, fever, and malaise. The symptoms usually persist for between 24 hours and a week, but may be longer. Diarrhea can vary in severity from loose stools to bloody stools. No antibiotics are usually given as the disease is self-limiting, however, severe or prolonged cases may require ciprofloxacin, erythromycin or norfloxacin. Fluid and electrolyte replacement may be required for serious cases.
[edit] Laboratory characteristics
Campylobacter is grown on specially selective "CAMP" agar plates at 42°C, the normal avian body temperature, rather than at 37°C, the temperature at which most other pathogenic bacteria are grown. Since the colonies are oxidase positive, they will usually only grow in scanty amounts on the plates. Microaerophilic conditions are required for luxurious growth.
Characteristic | Result |
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Growth at 25°C |
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Growth at 35-37°C |
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Growth at 42°C |
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Nitrate reduction |
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Catalase test |
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Oxidase test |
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Growth on MacConkey agar |
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Motility (wet mount) |
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Glucose utilization |
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Hippurate hydrolysis |
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Resistance to naladixic acid |
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Resistance to cephalothin |
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[edit] References
- Multiple Campylobacter Genomes Sequenced. PLoS Biol 3(1): e40. (2005)
- Ryan KJ; Ray CG (editors) (2004). Sherris Medical Microbiology, 4th ed., McGraw Hill. ISBN 0-8385-8529-9.
- Gorbach, Sherwood L., Falagas, Matthew (editors) (2001). The 5 minute infectious diseases consult, 1st ed., Lippincott Williams & Wilkins. ISBN 0-683-30736-3.
- Online Bacteriological Analytical Manual, Chapter 7: Campylobacter - US Center for Food Safety & Applied Nutrition (accessed 13 October 2006)