Helicobacter spp. in cats: association between infecting species and epithelial proliferation within the gastric lamina propria

Helicobacter spp. in the Stomach of Cats: Successful Colonization and Absence of Relevant Histopathological Alterations Reveals High Adaptation to the Host Gastric Niche

In addition to Helicobacter pylori, many non-Helicobacter pylori Helicobacters (NHPH) are able to cause gastric disease in humans. Cats are a natural reservoir for many of these species. Accordingly, living in close and intimate contact with animals has been identified as a risk factor, and an important zoonotic significance has therefore been attributed to NHPH. To determine the prevalence and associated gastric histopathological changes of Helicobacter species, the gastric mucosa of 71 cats were evaluated. Only four presented normal histopathological mucosa with the absence of spiral-shaped organisms. Normal gastric mucosa and the presence of spiral-shaped bacteria were observed in 13 cats. The remaining animals presented histopathological changes representative of gastritis. Helicobacter species were detected in 53 cats (74.6%) by at least one detection method. None of the animals were positive for H. pylori or for H. ailurogastricus. Helicobacter heilmannii organisms were identified in 20 animals, predominantly in the body gastric region. Helicobacter salomonis was the second most prevalent species (57.1%), although it was mainly found in association with other NHPH. Helicobacter felis and H. bizzozeronii were less frequently detected. The great majority of the Helicobacter spp. PCR-positive animals presented normal features regarding fibrosis/mucosal atrophy, neutrophils, eosinophils, or other inflammatory cells and lymphofollicular hyperplasia. Given the controversy and the strong evidence of absence of significant histopathological alterations associated with the presence of Helicobacter spp. in cats, it is possible to hypothesize that these bacteria may be able to adapt to the feline gastric microenvironment or even to comprise part of the gastric microbiome of this animal species. Thus, prudency must be taken when prescribing an antibiotic therapy based solely on the presence of these bacteria in the feline stomach.

Helicobacter genus in the intestine and liver of stray cats: the molecular, histopathological, and immunohistochemical study

OBJECTIVES

The study was designed to determine the presence of Helicobacter genus and three species of H. pylori, H. bilis, and H. canis, in the duodenum, ileum, colon, and liver of stray cats. Moreover, the histopathological and immunohistochemical analyses have been performed.

METHODS

Samples were taken from the duodenum, ileum, colon, and liver of 30 cats for molecular and histopathological evaluations. Polymerase chain reaction was carried out for the detection of the Helicobacter genus in the mentioned samples. Then, species-specific primers were used in Helicobacter-positive samples.

RESULTS

Helicobacter genus prevalence rates in the duodenum, ileum, colon, and liver samples were 50%, 60%, 50%, and 43.3%, respectively. Helicobacter pylori, H. canis, and H. bilis were isolated from at least one tissue of 18 (60%), 13 (43.3%), and 8 (26.7%) of the cats, respectively. Immunohistochemical findings confirmed the presence of bacteria in the intestinal crypt or the mucosal layer of duodenum, ileum, colon, and hepatic sinusoids.

CONCLUSION

In the present study, the concurrent infection of duodenum and liver was noticeable. Furthermore, the high prevalence of H. pylori in cats, as a well-known human pathogen, should be considered. High incidence of Helicobacter in gut and liver of Ahvaz stray cats is noticeable. According to the zoonotic importance of Helicobacter, more studies in the field of treatment and prevention are highly recommended.

Epidermal growth factor receptor 2 immunoexpression in gastric cells of domestic cats with H. heilmannii infection

The aim of this study was to evaluate the immunoexpression of HER-2 in gastric cells of cats infected with Non H. pylori Helicobacter (NHPH) and to investigate an association with the presence of inflammatory infiltrate. Forty-eight paraffin-embedded gastric samples were retrieved from the archives of the Veterinary Anatomic Pathology Laboratory that had previously been shown to be positive for NHPH with the rapid urease test and cytology. Infection by NHPH was confirmed by histopathology using the Warthin-Starry staining. Hematoxylin-eosin stained sections were reviewed to evaluate inflammatory cell infiltrates. Immunohistochemical analysis was done using anti- H. pylori antibody and anti-HER-2 antibody. Molecular analysis was performed by PCR to confirm the presence of Helicobacter. Statistical analysis was performed to determine whether there was an association between the presence of H. Heilmannii and HER-2 expression in gastric samples. All samples were positive for NHPH, by immunohistochemistry, and confirmed by PCR as H. Heilmannii. On histopathologic analysis, 56,3% of the samples had lymphocytes and plasma cells infiltrates, 52,1% of which were mild and 4,2% moderate. The intensity of the inflammatory infiltrate in the gastric mucosa was significantly greater in the complete plasma membrane of parietal cells of gastric glands that had greater HER-2 immunoexpression (p = 0.0001). A statistically significant association (p = 0.007) between the H. Heilmannii infection score and the expression of HER-2 in the lateral membrane of gastric surface cells was observed. HER-2 expression may be increased in feline gastric cells infected by H. Heilmannii and in parietal cells of gastric glands with an increased inflammatory infiltrate.

Helicobacter infection in the hepatobiliary system and hepatic lesions: a possible association in dogs

Helicobacter infection has been associated with hepatobiliary diseases in humans and animals. The aims of this study were to identify Helicobacter species in the hepatobiliary tract of dogs and to elucidate the possible association of these bacteria in liver diseases. Twenty-seven gastric and hepatobiliary samples were collected from 33 dogs with hepatic lesions and 17 dogs with no liver histological changes. Warthin-Starry staining, immunohistochemical assay, and PCR were performed to detect the presence of Helicobacter. Helicobacter genus was detected in 21.2% of the samples with hepatic lesions. The main lesion was chronic hepatitis. Immunohistochemistry revealed infection in liver (1/5) and gallbladder (1/3) 32 samples. The sequence analysis of seven amplicons of the 16S rRNA gene of Helicobacter genus from hepatobiliary samples showed 97.8 to 100% of nucleotide identity with gastric helicobacter. One amplicon of the ureA and ureB gene of Helicobacter genus from the stomach showed 89.1 to 90.7% nucleotide identity with H. heilmannii. The presence of Helicobacter genus in liver samples showing hepatic lesions suggests the involvement of these bacteria in the etiology of hepatobiliary disease in dogs. DNA sequences were similar to gastric Helicobacter species, reinforcing the hypothesis of bacterial translocation from the stomach to liver by the biliary pathway.

A mixed population of Helicobacter pylori, Helicobacter bizzozeronii and "Helicobacter heilmannii" in the gastric mucosa of a domestic cat

Background

The presence of Helicobacter within the gastric mucosa is responsible for producing pathology in many animal species, including man. Since humans have been shown to harbour many of the same bacterial species as domestic carnivores, concern over their zoonotic potential has been growing. Helicobacter pylori, a class 1 carcinogen responsible for cases of gastritis and gastric cancer in humans, produces similar pathology in pet carnivores and is considered an example of anthroponosis. The case here presented refers to a 13 year-old mixed breed spayed female cat seen at necropsy.

Findings

Stomach samples were analysed for the presence of Helicobacter spp. by cytology, histopathology and PCR. Mild mucosal atrophy was observed in the fundus and antrum, while lymphoplasmocytic infiltrates where noted in the lamina propria of the antrum. Helicobacter-like organisms were observed in the corpus and antrum, occupying gastric glands and surface mucosa. It was possible to detect Helicobacter spp., H. pylori, H. heilmannii and H. bizzozeronii in the fundus, corpus and antrum by PCR, while in the antrum PCR samples were positive for H. pylori.

Conclusions

The spayed female under study could represent either a yet un-described population of domestic cats infected with H. pylori or a case of anthroponosis.

Mechanisms, causes, investigation and management of vomiting disorders in cats: a literature review

Vomiting is a common presenting complaint in feline practice. This article differs from previous reviews in that it is an evidence-based review of the mechanisms, causes, investigation and management of vomiting in the domestic cat. Published evidence was reviewed, and then used to make recommendations for clinical assessment, diagnosis, antiemetic drug treatment, dietary management and monitoring of cats presenting with vomiting. The strength of the evidence on which recommendations are made (and areas where evidence is lacking for cats) has been highlighted throughout.

High prevalence of dna from non-H. pylori helicobacters in the gastric mucosa of venezuelan pet dogs and its histological alterations

Non-H. pylori helicobacters (NHPH) have been demonstrated as gastric spiral-shaped bacteria in specimens obtained from dogs; however, their roles in the pathogenesis of upper gastrointestinal disease have not yet been clearly established. The purpose of this study was to evaluate the prevalence of NHPH DNA in the gastric mucosa of dogs and its association with histopathology. Helicobacter was detected through histopathological techniques, PCR, and FISH analysis from fundic biopsies of twenty dogs with or without signs of gastrointestinal disease. PCR and FISH were based on partial 16S rRNA gene sequences. Nineteen dogs showed mild to marked gastritis in the fundus, and only one dog had a healthy gastric mucosa. NHPH DNA was detected in 18 dogs with gastritis and one with normal gastric mucosa. However, there was no significant correlation between the presence of NHPH DNA and the degree of gastritis. These results show a high prevalence of NHPH DNA in the gastric mucosa of dogs from Venezuela. Further studies are necessary to determine a possible association between a specific NHPH species and the degree of gastritis.

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

PURPOSE: To analyze the triple antimicrobial therapy in positive Helicobacter spp. dogs and to investigate recurrence. METHODS: A total of 20 dogs underwent endoscopy followed by gastric biopsy using the rapid urease test and histopathology stained with Giemsa. Ten animals were treated with triple therapy recommended for humans and divided into control and experimental group. The control group was kept in isolation while the experimental group was placed in contact with positive animals during 60 days. RESULTS: The prevalence of infection in animals in this experiment was 100%, and more frequent in the fundus and the gastric body. Therapy for 7 days using clarithromycin, amoxicillin and lansoprazole was effective in 100% of the animals. Recurrence of the infection in 80% of dogs in the experimental group, while the control group remained eradicated after 60 days. CONCLUSION: Crowded environments associated with close contact with dogs infected with helicobacter are a determinant for transmission of Helicobacter spp. between canines.

Gastric helicobacter spp. Infection in captive neotropical brazilian feline

Ten captive neotropical Brazilian feline were submitted to gastroscopic examination and samples of gastric mucosa from fundus, corpus and pyloric antrum were evaluated for the presence of Helicobacter species. Warthin-Starry (WS) staining and PCR assay with species-specific primers and enzymatic cleavage were applied for bacterial detection and identification. Histological lesions were evaluated by haematoxylin and eosin staining. All animals showed normal gross aspect of gastric mucosa. Helicobacter heilmannii was confirmed in 100% of the samples by WS and PCR assay. Mild lymphocytic infiltrate in the lamina propria was observed in eight animals, mainly in the fundus region. Small lymphoid follicles were seen in three animals. No significant association between Helicobacter infection and histological findings was verified. These observations suggest that gastric Helicobacter spp. could be a commensal or a eventual pathogen to captive neotropical feline, and that procedures, way life, and stress level on the shelter apparently had no negative repercussion over the integrity of the stomach.

The efficacy and safety of long-term Helicobacter species quadruple therapy in asymptomatic cats with naturally acquired infection

Owing to rising drug-resistant Helicobacter species infections in people and animals, currently therapies are losing their efficacy; therefore, regimens efficacious in the presence of drug resistance are needed. This study assessed the efficacy and safety of a 14-day quadruple Helicobacter species therapy in cats with naturally acquired infection. Thirteen asymptomatic adult stray cats with Helicobacter species infection (identified by analysis of gastric biopsies using polymerase chain reaction and Helicobacter-specific primers) received omeprazole 0.7mg/kg q 8h plus amoxicillin 20mg/kg q 12h, metronidazole 20mg/kg q 12h and clarithromycin 7.5mg/kg q 12h, for 14 days. Second molecular analysis of gastric biopsies revealed persistence of Helicobacter species DNA in four cats that were negative on quantitative urease testing, cytology and histopathology. Our results suggest that antibiotic regimens that are effective against Helicobacter pylori in people cannot eradicate Helicobacter species in cats with naturally acquired infection, although transient suppression may occur.

Helicobacter spp. other than Helicobacter pylori

Over the last 12 months, new insights into the association of non-Helicobacter pylori Helicobacters with a range of human diseases in children and adults, including hepatobiliary disease, Crohn's disease, sepsis, and gastric disease were published. Studies investigating the presence of non-H. pylori Helicobacters in domestic animals reinforce previous findings that cats and dogs harbor gastric Helicobacter species and thus may be an important source of these organisms in humans. The confounding effect of enterohepatic Helicobacters on the outcome of biomedical research was investigated in several studies and led to recommendations that animals should be screened prior to performing experiments. A number of important and novel investigations regarding pathogenic mechanisms and immune responses to enterohepatic Helicobacters were conducted. Genomic advances in non-H. pylori Helicobacters included description of the complete genome of Helicobacter canadensis, delineation of two Helicobacter bilis genomospecies, and identification of a novel cis-regulatory RNA. New insights concerning growth conditions, biochemical characterization, and the effect of certain dietary compounds on Helicobacter spp. have also been reported.

Helicobacter species detection and histopathological changes in stray cats from Niterói, Brazil

Tightly coiled bacteria are common inhabitants of the gastric mucosae of cats and there is considerable debate whether feline helicobacters are commensal or pathogenic organisms. To determine the prevalence of Helicobacter species and gastric histopathological findings, gastric mucosa samples of 56 stray cats were collected from cardia, fundus, body, antrum and pylorus at necropsy. The samples were examined by urease test, cytology, histopathology and culture. Helicobacter species were detected in 53 cats (94.6%) by at least one detection method. Urease test results were positive in gastric samples from 50 (89.3%) cats. Cytological and histological evaluations revealed Helicobacter species in 52 (92.8%) and 50 (89.2%) cats, respectively. Helicobacter species organisms were not cultured from any cat. Regardless of the presence of gastric bacteria, most of the cats had mild to moderate gastritis. These data reveal a high prevalence of Helicobacter species in stray cats from Niterói, Brazil.

Identification of Helicobacter spp. in oral secretions vs. gastric mucosa of stray cats

The definite mode of transmission of Helicobacter infection is largely unknown. This study was carried out primarily, to determine the existence of Helicobacter spp. in the oral secretions of stray cats as one of the possible routes of transmission and secondly, to evaluate the accordance between oral and gastric colonization of Helicobacter spp. in these cats. Forty-three adult stray cats were thus studied for the presence of Helicobacter species by quantitative rapid urease test (RUT), cytology and PCR. Helicobacter spp. were found in the oral secretions and gastric biopsies of 93% and 67.5% of the stray cats, respectively. There was not, however, any agreement observed between Helicobacter colonization at these two locations, at neither genus nor species level. These findings suggest that the oral cavity is routinely exposed to transient forms of bacteria and may temporarily harbor Helicobacter spp. Thus, oral cavity as a source of Helicobacter spp. may act as a reservoir for transmission and may not necessarily reflect the colonization status of the gastric mucosa.