Helicobacter Infection in Dogs and Cats: Facts and Fiction

Abstract

The discovery of the spiral bacterium Helicobacter pylori and its causative role in gastric disease in humans has brought a dramatic change to gastroenterology. Although spiral bacteria have been known for more than a century to infect the stomachs of dogs and cats, recent research has been conducted mainly in the wake of interest in H. pylori. H. pylori has not been found in dogs and only very rarely in cats and zoonotic risk is minimal. A variety of other Helicobacter spp. can infect the stomach of pets; however, their pathogenic role is far from clear, and they have a small but real zoonotic potential. The prevalence of gastric Helicobacter spp. in dogs and cats is high, irrespective of clinical signs, and as in human medicine, mode of transmission is unclear. The relationship of Helicobacter spp. to gastric inflammation in cats and dogs is unresolved, with inflammation, glandular degeneration, and lymphoid follicle hyperplasia accompanying infection in some but not all subjects. Circulating anti-Helicobacter immunoglobulin G antibodies have been detected in 80% of dogs with naturally acquired infection and most dogs and cats with experimental infection. The gastric secretory axis is similar in infected and uninfected cats and dogs and no relationship of infection to gastrointestinal ulcers has been found. Differences in the pathogenicity of Helicobacter spp. are apparent, because infection with H pylori is associated with a more severe gastritis than infection with other Helicobacter spp. in both cats and dogs. Rapid urease test, histopathology, and touch cytology are all highly accurate invasive diagnostic tests for gastric Helicobacter-like organisms in dogs and cats, whereas culture and polymerase chain reaction are the only means to identify them to the species level. Urea breath and blood tests or serology can be used to diagnose Helicobacter spp. noninvasively in dogs and cats. Most therapeutic studies in pets have not shown long-term eradication of Helicobacter spp. Whether this is due to reinfection or recrudescence has not been established.

Studies of distribution and recurrence of Helicobacter spp. gastric mucosa of dogs after triple therapy

“…were seen in the mucus, over the tissue surface, at the crypt bottom and inside the gastric glands, adding that in this research the bacteria density was higher in areas with more mucus 6,7 .…”

“…are frequently found in dogs [6][7][8]15 , not only in healthy animals 15 , but also in dogs with gastropathy simptoms 7 .…”

“…The bacteria prevalence in street dogs and in dogs which live in crowded areas like, city kennels in Brazil is between 90% to 100% 6,7,15,21 . In a retrospective study performed in Colombia shows that the Helicobacter spp.…”

“…Stained histopathology by Giemsa and modified Giemsa allowed us easy seeing and microorganism identification at the positive urease test. The urease fast test negative result and the tests which the color change time occurred above 2 hours were related to histopathologic exams with helicobacter absence or low colonization density 7,[21][22][23][24] . This work showed good concordance between the urease test and histopathology according Kappa coefficient.…”

Gastrointestinal microorganisms in cats and dogs: a brief review

“…An early study used several detection techniques and showed that the stomach of 91% of pet cats (n=58) were positive for the genus Helicobacter (Neiger et al 1998), suggesting a high occurrence of this bacterial group in the feline stomach. In another study, it was shown that cats and dogs are predominantly coloniszed by H. heilmannii (Priestnall et al 2004) but other species (e.g., H. felis, H. bizzozeronii, H. salomonis, H. pametensis) have also been identified in these animal species (Neiger and Simpson 2000).…”