Campylobacter Jejuni: Disease, properties and Laboratory diagnosis

Campylobacter usually causes diarrhea (often bloody). It is the most common causes of gastroenteritis worldwide, enterocolitis especially in children. It causes systemic infection (rarely) in children and debilitated adults. Systemic infections (bacteremia), mostly by Campylobacter intestinalis.

Drug Resistant Campylobacter serious threat to human being
Drug Resistant Campylobacter serious threat to human being

Drug-Resistant Campylobacter is one of the top 18 drug-resistant threats to the United States. CDC has categorized it under “Serious concern”.




Important properties of Campylobacter jejuni:

Campylobacter: Amphitrichous (bipolar) flagella
Campylobacter: Amphitrichous (bipolar) flagella
  • Curved, gram-negative rods that appear either comma or S-shaped.
  • Microaerophilic (growing best in 5% oxygen rather than in  the 20% present in the atmosphere): More info about oxygen requirements of bacteria
  • Campylobacter jejuni grows well at 42 degree Celsius
  • Oxidase Positive
  • Posses Amphitrichous (bipolar) flagella

Disease Transmission

  1. Source: Cattle, Chicken, Dogs etc
  2. Mode of transmission: Faecal-oral route {food (milk or meat products) and water contaminated with animal feces}. Human to Human transmission can occur but less frequent. 

Reservoir of infection: Domestic animals such as cattle, chicken, dogs etc


  1. Symptoms (within 2-5 days of exposure):
    • Watery foul smelling diarrhea (may be bloody)
    • Nausea and vomiting (may seen)
    • cramping
    • Severe abdominal pain
    • and fever
  2. Can be treated with antibiotics
  3. Usually self limiting disease and typically lasts about one week.
  4. Some infected persons do not have any symptoms.

Campylobacter infections are also associated with some autoimmune diseases:

  1. Guillain-Barré Syndrome
  2. Reactive arthritis
  3. Reiter’s syndrome


Mechanism of Guilian-Barre Syndrome
Mechanism of Guillain-Barré Syndrome

Guillain-Barré Syndrome

  1. GI infection with C. jejuni is associated with Guillain-Barré Syndrome
  2. Most common cause of acute neuro-muscular paralysis
  3. Autoimmune disease
  4. 40% caused by C. jejuni infection
  5. Formation of antibodies against C. jejuni that cross reacts with antigens on neurons.
  6. Immune system attacks own nerves
  7. axons are attacked by antibodies against the bacteria C. jejuni, which react with proteins of the peripheral nerves.

Reactive arthritis (Reiter’s syndrome)

  1. Infection with jejuni is also associated with Reactive arthritis (Reiter’s syndrome)
  2. Painful swelling of joints often the knees and/or ankles.
  3. Other bacteriag. Chlamydia trachomatis, Salmonella, Shigella, Yersinia also causes Reactive arthritis.

Campylobacter jejuni: Curve, S shaped gram negative bacteria
Campylobacter jejuni: Curve, S shaped gram negative bacteria

Pathogenesis/Virulence: Campylobacter jejuni produces enterotoxins and cytotoxins

Laboratory diagnosis:

Specimen: Diarrhoeal or dysenteric specimen containing blood, pus and mucus. If immediate processing is not feasible specimen can be refrigerated up to 24 hours before culture as the organism are resistant to cold temperature.

  • Blood agar plates containing antibiotic (to inhibit the fecal flora) is the media of choice. Inoculated plates are incubated at 42oC in a microaerophilic atmosphere containing 5% oxygen and 10% carbon dioxide.
  • Failure to grow at 25oC
  • Oxidase test: positive
  • Catalse test: Positive
  • Sensitive to Nalidixic acid

Note: Campylobacter intestinalis does not grow at 42oC, but grows at 25oC and is resistance to Nalidixic acid.

Drugs of choice for Campylobacter infection: Erythromycin or Ciprofloxacin is used successfully in Campylobacter jejuni enterocolitis.

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