Campylobacteriosis - Dogs and Cats

Introduction

Campylobacter are curved, gram negative, micraerophilic bacteria that parasitise the alimentary tract of animals. Campylobacter jejuni is the most common cause of food poisoning in man, therefore making this a zoonotic disease and a public health issue.

The pathogen is very common on farms, particularly poultry, cattle and sheep farms. Dogs and cats can harbour the disease too (usually farm animals) and in these cases if the dog has been exposed to it throughout life they are generally immune. The pathogen can cause diarrhoea and clinical signs in dogs and cats that live in a hygienic environment as these are not exposed to the pathogen on a regular basis.

The bacteria are present in the intestinal tract of animals and are transmitted via the faecal-oral route. C. jejuni then causes colitis by necrosis of absorptive epithelial cells and erosion of the mucosa. Flaggellae play an important role in colonisation.

At slaughter of broiler chickens, the intestinal contents may be spread around the abdominal cavity of the bird. Therefore most poultry will be moderately to heavily contaminated with the pathogen. If thawing of a frozen bird is inadequate, the organism may still be viable in the abdominal cavity or it may be ingested by humans handling raw meat.

Signalment

Pet dogs are likely to show clinical signs if they become infected with Campylobacter, as unlike farm dogs, they are not exposed to the pathogen on a daily basis. The disease can affect dogs of any age, breed or sex. Immunocompromised animals will suffer from more severe clinical signs. Humans can also be infected by the pathogen.

Clinical Signs

Signs include large intestinal diarrhoea; presence of blood and possible mucous with increased frequency of defecation and possible tenesmus. Abdominal pain characterised by head turning towards the abdomen and restlessness/changing posture regularly and appearing generally uncomfortable. The animal may also be pyrexic.

Diagnosis

Faecal samples can be sent to the laboratory for culture under microaerophilic conditions. A commercial test kit using latex agglutination is also available. Retrospective diagnosis can be presumed following resolution after antibiotic treatment.

Treatment

The antibiotics Vancomycin, Trimethoprim and Polymyxin B are all effective in treating this condition. Supportive therapy should also be given in cases of severe diarrhoea, such as fluid therapy to help prevent dehydration and NSAIDs to reduce pyrexia. Plain food such as chicken and rice should be given after a 24hour starvation, which is the case for all cases of diarrhoea in dogs.

Prognosis

Excellent; resolution following appropriate treatment.

References

Blood, D.C. and Studdert, V. P. (1999) Saunders Comprehensive Veterinary Dictionary (2nd Edition), Elsevier Scienc.
Ettinger, S.J, Feldman, E.C. (2005) Textbook of Veterinary Internal Medicine (6th edition, volume 2), W.B. Saunders Company.
Hall, E.J, Simpson, J.W. and Williams, D.A. (2005) BSAVA Manual of Canine and Feline Gastroenterology (2nd Edition), British Small Animal Veterinary Association.
Nelson, R.W. and Couto, C.G. (2009) Small Animal Internal Medicine (Fourth Edition), Mosby Elsevier.
Tams, T.R. (2003) Handbook of Small Animal Gastroenterology (2nd edition), Saunders.
Tilley, L.P. and Smith, F.W.K.(2004)The 5-minute Veterinary Consult (Third edition), Lippincott, Williams & Wilkins.