Campylobacter spp

Last week we learned several bacteria which could cause gastrointestinal infection. In the lab, I have been assigned a case study for campylobacter jejuni. Now I would like to share more info about Campylobacter spp.

Campylobacter spp could cause both diarrheal and systemic diseases, and the most common specie is Campylobacter jejuni. 

Campylobacter spp are Gram-negative rods with comma, S, or “gull-wing” shapes. They are motile, with a single polar flagellum, no spore or capsule. 

They could be cultured in an atmosphere with reduced O₂ (5% O₂) with added CO₂ (10% CO₂), at 42 ℃. Several selective media can be used, for eample, Skirrow’s medium. The colonies appear as watery and spreading, round and convex. 

Virulence factors are lipopolysaccharides (LPS) with endotoxic activity, cytopathic extracellular toxins and enterotoxins. 

The pathogenesis of the infection are: 1) The infection by oral route from food, drink, or contact with infected animals or animal products (Milk, meat products ); 2) Susceptible to gastric acid (about 10⁴ organisums); 3) Multiply in the small intestine invade the epithium produce inflammation  cause bloody stools. Occasionally, the bloodstream is invaded.

The symptoms for the infection usually are diarrhea, malaise, fever, abdominal pain. 

The diagnostic laboratory test is diarrheal stool specimen smears and culture. Smears: Gram-stained smears of stool may show the typical “gull-shaped” rods. Culture: (have been described above).

The control of the infection would be to control the source of infection which may be food (eg, milk, under-cooked fowl) or contract with infected animals or humans and their excreta.