Helicobacter

Overview

Helicobacter spp. are related to Campylobacter species and Arcobacter species and are pathogens affecting the stomach and intestines. There are several species identified in humans and many veterinary species where the incidence of some species of Helicobacter is high. The genus is considered of low pathogenic significance in veterinary species but there is possibility of zoonosis of the H. pylori species that is the causitve agent of gastric disease in humans.

A bacterial pathogen of the intestines
Discovered in the stomach of humans in 1987
H. felis, H. bizzozeronii, H. salomonis and H. bilis found in gastric mucosa and intestines of dogs and cats

Characteristics

Helicobacter are gram negative rod bacteria, they can appear helical, S-shaped or curved.

Helical, S-shaped or curved Gram negative rods
Require enriched media; some grow on Skirrow agar
Microaerophilic, non-saccharolytic
Oxidase positive and catalase positive except for H. canis
Helicobacters which colonise gastric mucosa are urease positive

Clinical infections

Helicobacter pylori causes gastritis and duodenal and gastric ulcers in humans
Association with gastric adenocarcinoma in humans
H. mustelae has been associated with chronic gastritis and gastric ulcers in ferrets
Significance in gastrointestinal diseases of domestic carnivores not known

Carried in the stomach of a high proportion of people.
- 60% in the elderly.
Implicated in the development of peptic ulcers and gastritis in people.
Strong epidemiological evidence for the involvement of H. pylori in human gastric neoplasia.
- No evidence this is the case for animals.
Several species demonstrated in dogs: H. felis, H. bizzozeronii, H. salomonis and H. bilis.
- Present in around 80% of clinically healthy pet dogs.
  - Up to 100% in dogs from animal shelters.
Experimental infection of dogs has failed to show a consistent relationship between infection with Helicobacter and pathology.
- Inflammation accompanies infection in some but not all infected dogs.