Strategy for the detection of Helicobacter species by amplification of 16S rRNA genes and identification of H. felis in a human gastric biopsy

Modulation Effects of Sargassum pallidum Extract on Hyperglycemia and Hyperlipidemia in Type 2 Diabetic Mice

The aim of this study was to investigate the antidiabetic effect of the extract from Sargassum pallidum (SPPE) on type 2 diabetes mellitus (T2DM) mice. SPPE treatment alleviated hyperglycemia, insulin resistance (IR), liver and pancreatic tissue damage, hyperlipidemia and hepatic oxidative stress resulting from T2DM. SPPE reversed phosphoenolpyruvate carboxylase (PEPCK) and hexokinase (HK) activities to improve gluconeogenesis and glycogen storage in the liver. Furthermore, SPPE modulated glucose metabolism by regulating the levels of mRNA expression involving the PI3K/Akt/FOXO1/G6pase/GLUT2 pathway and could inhibit fatty acid synthesis by reducing the gene expression levels of fatty acid synthase (FAS) and acetyl-CoA carboxylase-1 (ACC-1). A 16 sRNA analysis indicated that SPPE treatment also reversed gut dysbiosis by increasing the abundance of beneficial bacteria (Bacteroides and Lactobacillus) and suppressing the proliferation of harmful bacteria (Enterococcus and Helicobacter). Untargeted metabolomics results indicated that histidine metabolism, nicotinate and nicotinamide metabolism and fatty acid biosynthesis were significantly influenced by SPPE. Thus, SPPE may be applied as an effective dietary supplement or drug in the management of T2DM.

Investigation with Real-Time PCR and Histopathology on the presence of H. felis, H. heilmannii and H. pylori in dogs

Helicobacter species such as H. heilmannii, H. pylori, H. felis, H. bizzozeronii and H. salomonis have been identified in cats and dogs, and research suggesting that these species may be zoonotic agents and has been studied intensified in recent years. The aim of this study was to reveal the presence, comparing the histopathological findings and Real-time PCR results of H. felis, H. heilmannii, and H. pylori in the stomach and liver tissues taken during the necropsies of owned, stray or shelter dogs. The material of the study consisted of stomach and liver tissues taken from 35 dogs that died for different reasons and were brought for necropsy. DNA copies of H. heilmannii were detected by Real-time PCR in the liver samples of 30 dogs using H. heilmannii-specific primers. In the case of gastric samples, Real-time PCR detected H. heilmannii in 13 cases, H. pylori in 3 cases, both H. heilmannii and H. pylori in 13 cases, and H. felis, H. heilmannii and H. pylori in 3 cases. Microscopically, neutrophil leukocyte infiltration, epithelial degeneration, fibrosis and oedema in the lamina propia, and lymphoplasmacytic cell infiltration were determined in the stomachs. In the Hemotoxylin Eosin staining of the sections, 5 cases and 14 cases in the Warthin–Starry staining were found positive for Helicobacter-like microorganisms. Microscopically, dissociation of the remark cords and hydropic degeneration in hepatocytes, and focal mononuclear cell infiltrations in some sections were determined in the livers. In conclusion, with this study, it was understood that Real-time PCR analyzes are very useful in the diagnosis of H. felis, H. heilmannii, and H. pylori. However, histopathological examinations are necessary to associate the presence of bacteria with the development of the disease.

Effect of a Probiotic Mixture in Captive Cheetahs (Acinonyx Jubatus) with Gastrointestinal Symptoms—A Pilot Study

Simple Summary

In recent years, many studies have demonstrated the effectiveness of probiotics in acute and chronic gastrointestinal disorders in both humans and animals. The objective of this study is to evaluate the effect of a specific probiotic mixture in cheetahs. In the wild, cheetah populations have drastically reduced due to habitat destruction, human–wildlife conflict and illegal wildlife trade. In captivity, chronic gastrointestinal diseases have a high prevalence. Based on our results, it can be concluded that probiotics may be helpful as a dietary supplement in cheetahs suffering from gastrointestinal disease.

Abstract

Cheetahs (Acinonyx jubatus) are classified as “vulnerable” species due to the low numbers persisting in the wild. Gastrointestinal diseases are very common in this species when they are kept in captivity, in particular gastritis. Clinical signs are predominantly characterized by vomiting, diarrhea, weight loss and anorexia. In this study, we evaluated the efficacy of a multi-strain probiotic in two groups of cheetahs: Group A (n = 4)—rescued cheetahs housed at the Cheetah Conservation Fund (Otjiwarongo, Namibia); Group B (n = 9)—captive cheetahs housed in Italian zoos. Animals showed gastrointestinal signs of different severity, and were positive for Helicobacter spp., detected by PCR in stool samples. Two sachets of probiotic formulation were administered to all cheetahs once a day for 21 consecutive days. Clinical conditions (appetite loss, vomiting, stool consistency and Body Condition Score) before (T0) and after 21 days of probiotic administration (T1) were then compared using a simplified Feline Chronic Enteropathy Activity Index (FCEAI) score. A slight but not significant improvement in the scores was observed in Group A, which had mild intestinal symptoms, while a significant decrease in vomiting and stool consistency (**p < 0.01) scores was observed in Group B, which had more pronounced symptoms. Results suggest that high concentrations of live probiotics can be of help in managing gastrointestinal signs in cheetahs.

DNA diagnostics for reliable and universal identification of Helicobacter pylori

Reliable diagnostics are a major challenge for the detection and treatment of Helicobacter pylori (H. pylori) infection. Currently at the forefront are non-invasive urea breath test (UBT) and stool antigen test (SAT). Polymerase chain reaction (PCR) is not endorsed due to nonspecific primers and the threat of false-positives. The specificity of DNA amplification can be achieved by nested PCR (NPCR), which involves two rounds of PCR. If the primers are properly designed for the variable regions of the 16S rRNA gene, it is not difficult to develop an NPCR assay for the unambiguous identification of H. pylori. Elaborate NPCR for a 454 bp amplicon was validated on 81 clinical biopsy, stool, and saliva samples, each from the same individuals, and compared with available H. pylori assays, namely histology, rapid urease test, SAT, and ¹³C-UBT. The assay was much more sensitive than simple PCR, and it was equally sensitive in biopsy samples as the ¹³C-UBT test, which is considered the gold standard. In addition, it is sufficiently specific because sequencing of the PCR products exclusively confirmed the presence of H. pylori-specific DNA. However, due to the threshold and lower abundance, the sensitivity was much lower in amplifications from stool or saliva. Reliable detection in saliva also complicates the ability of H. pylori to survive in the oral cavity aside from and independent of the stomach. The reason for the lower sensitivity in stool is DNA degradation; therefore, a new NPCR assay was developed to obtain a shorter 148 bp 16S rRNA amplicon. The assay was validated on stool samples from 208 gastroenterological patients and compared to SAT results. Surprisingly, this NPCR revealed the presence of H. pylori in twice the number of samples as SAT, indicating that many patients are misdiagnosed, not treated by antibiotics, and their problems are interpreted as chronic. Thus, it is unclear how to properly diagnose H. pylori in practice. In the first approach, SAT or UBT is sufficient. If samples are negative, the 148 bp amplicon NPCR assay should be performed. If problems persist, patients should not be considered negative, but due to threshold H. pylori abundance, they should be periodically tested. The advantage of NPCR over UBT is that it can be used universally, including questionable samples taken from patients with achlorhydria, receiving proton pump inhibitors, antibiotics, bismuth compound, intestinal metaplasia, or gastric ulcer bleeding.

A report of nonexistence of the non-Helicobacter pylori Helicobacter species in Iranian patients suffering from inflammatory bowel disease

Inflammatory bowel disease is a chronic, relapsing-remitting gastrointestinal disorder which has become a serious global concern, and it imposes a great degree of health and economic burdens on communities worldwide. Although the presence of non-Helicobacter pylori Helicobacter (NHPH) microorganisms has been reported in various gastrointestinal disorders, their putative role in the pathogenesis of IBD has been a matter of controversy. The present study aimed to investigate the existence of gastric and enterohepatic NHPHs and their probable coinfection with H. pylori in IBD. Totally, 168 clinical specimens including 70 colonic biopsies and 98 fecal specimens were obtained from IBD patients. Genomic DNA was extracted from all samples, and its quality and concentration were assessed by β-globin PCR and spectrophotometry. The Helicobacter genus-specific PCR was performed using 16S rRNA gene. All samples were also tested for H. pylori infection by PCR of ureC gene fragment (glmM). The presence of NHPH was examined by using species-specific PCR assays. Based on PCR results, H. pylori was detected in 12.9% and 3.1% of colonic biopsies and fecal specimens, respectively. However, no statistically significant correlation was observed (P value > 0.05). We failed to find NHPH in both colonic biopsies and fecal specimens from IBD patients. Despite the fact that none of the IBD patients harbored the NHPH in the current work, further cohorts with larger sample size are required to determine the possible relationship between NHPH infection and IBD pathogenesis.

Occurrence of Helicobacter spp. and Fecal Bacterial Contamination in High-altitude Aquatic Environments from the Andes

The occurrence of Helicobacter spp. and fecal bacterial contamination was investigated in high-altitude environments from the Northeastern Andes of Venezuela. Helicobacter DNA was detected by PCR in streams, drinking and irrigation waters, and one culture from drinking water by the HP enrichment medium for selection of Helicobacter pylori, which displayed 98.98% homology to this pathogen based on 16S rRNA gene sequencing. FISH demonstrated predominant coccoid cells of the target bacteria indicative of the viable but nonculturable (VBNC) state in all water samples and HP cultures. Our work reveals for the first time Helicobacter spp. in waters from one of the highest places in the world. These results, together with the presence of fecal coliforms (2-160 MPN/100 mL) from the headwaters of rivers to drinking and irrigation waters, alert fecal contamination and epidemiological implications in this area of ecological and economic importance for the region.

Evidence of Helicobacter spp. in Saliva and Gastric Mucosa of Domestic Dogs in the Central Region of Rio Grande do Sul, Brazil

Helicobacter pylori is a spiral-shaped bacterium, which plays a role in the aetiology of gastric diseases in humans. Non-H. pylori Helicobacter (NHPH) species naturally colonise the stomach of animals and also induce gastric lesions in humans, highlighting their zoonotic importance. We evaluated the gastric bacterial colonisation density and gastric lesions and sought to identify the main phylogenetic groups of the Helicobacter spp. obtained from dogs in the central region of Rio Grande do Sul, Brazil, with this study aiming to investigate the occurrence of Helicobacter spp. in saliva and gastric samples from these dogs. This study included 35 dogs and used analysis such as cytology, histopathology, PCR, rapid urease testing, and phylogenetic analysis. Of the dogs, 94.3% were positive for Helicobacter spp., and these bacteria were present in the stomach of 32 dogs and saliva of eight. Respectively, eight, 15, and nine dogs had mild, moderate, and severe colonisation. Lymphocytic-plasmacytic infiltrate was the main gastric lesion. However, the presence of Helicobacter and the density appeared to be unrelated to the gastric lesions. The samples possessed a high nucleotide identity with remarkably similar sequences among some of the species of NHPH such as H. heilmannii s.s., H. salomonis, H. felis, and H. bizzozeronii. The saliva of domestic dogs, even of those who appear clinically healthy, can cause Helicobacter infection in humans and other animals, with, in these dogs, increased density, occurrence rate, and predominance of NHPH of zoonotic importance being found in the stomach with a lower occurrence of Helicobacter spp. in the saliva.

First report of PCR-based detection of Helicobacter species DNA in Camelus dromedarius in Egypt

Background and Aim:

Helicobacter species infections have epidemiological and zoonotic impacts, and different species of Helicobacter have been implicated in infecting humans and animals. The aim of this study was to investigate Helicobacter species infections in Camelus dromedarius.

Materials and Methods:

Fecal samples were collected from 32 camels from 9 camel farms located at Ismailia Governorate, Egypt. The collected samples were investigated by bacteriological isolation and conventional polymerase chain reaction (PCR) assays targeting the 16S ribosomal RNA gene.

Results:

Although Helicobacter species could not be isolated from all the examined samples, Helicobacter DNA was detected in 2 (22.22%) of the 9 camel farms. Of the 32 camel fecal samples examined, 4 (12.5%) were positive for Helicobacter species as analyzed by the PCR assay.

Conclusion:

To the best of our knowledge, this is the first report of PCR-based detection of Helicobacter species infections in C. dromedarius. Further epidemiological studies are required to clarify Helicobacter species infections in camels.

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.

Changes in Intestinal Microbiota of Type 2 Diabetes in Mice in Response to Dietary Supplementation With Instant Tea or Matcha

OBJECTIVE

Gut microbiota plays a key role in metabolism and health in diabetes patients with gastrointestinal microbiota dysbiosis. Thus, regulating the ecological balance of gut microbiota may provide a pathway toward improvement for these patients. Our previous study showed that functional ingredients in tea may inhibit cornstarch digestion in vitro.

METHODS

A cornstarch-tea diet was developed, and in this study we investigated the effects of such a diet on blood glucose and gut microbiota in diabetic mice.

RESULTS

Diabetes resulted in significant weight loss, hyperphagia and hyperglycemia. 16S rDNA sequencing revealed that in diabetes there is significantly increased Bacteroidaceae, Helicobacteraceae, Ruminococcaceae, Enterobacteriaceae, Rikenellaceae and Saccharibacteria_genera_incertae_sedis, and significantly decreased Lactobacillaceae, Prevotellaceae, Coriobacteriaceae, Verrucomicrobiaceae and Bifidobacteriaceae. The cornstarch‒tea diet resulted in a trend toward reduced blood glucose, with particularly increased levels of Coriobacteriaceae, Lactobacillaceae, Prevotellaceae and Bifidobacteriaceae, and decreased Bacteroidaceae, Ruminococcaceae, Helicobacteraceae and Enterobacteriaceae.

CONCLUSIONS

Instant tea and matcha supplementation had beneficial effects on regulation of blood glucose and gut microbiota, reversing the changes in microbiota caused by alloxan injection. The cornstarch‒tea regulation pathway is involved in bacterium group regulation rather than single-species regulation, which suggests that cornstarch combined with tea may be used as a functional food supplement for diabetes patients.

Detection of Pathogenic and Non-pathogenic Bacteria in Drinking Water and Associated Biofilms on the Crow Reservation, Montana, USA

Private residences in rural areas with water systems that are not adequately regulated, monitored, and updated could have drinking water that poses a health risk. To investigate water quality on the Crow Reservation in Montana, water and biofilm samples were collected from 57 public buildings and private residences served by either treated municipal or individual groundwater well systems. Bacteriological quality was assessed including detection of fecal coliform bacteria and heterotrophic plate count (HPC) as well as three potentially pathogenic bacterial genera, Mycobacterium, Legionella, and Helicobacter. All three target genera were detected in drinking water systems on the Crow Reservation. Species detected included the opportunistic and frank pathogens Mycobacterium avium, Mycobacterium gordonae, Mycobacterium flavescens, Legionella pneumophila, and Helicobacter pylori. Additionally, there was an association between HPC bacteria and the presence of Mycobacterium and Legionella but not the presence of Helicobacter. This research has shown that groundwater and municipal drinking water systems on the Crow Reservation can harbor potential bacterial pathogens.

Point Mutations at gyrA and gyrB Genes of Levofloxacin-Resistant Helicobacter pylori Isolates in the Esophageal Mucosa from a Venezuelan Population

The treatment of Helicobacter pylori infection is complicated by antibiotic resistance. A high levofloxacin (LVX) resistance rate was previously demonstrated in H. pylori isolates from gastric mucosa (40%) and esophagus (19%) in individual hosts of a Venezuelan population. We aimed to assess the molecular mechanisms of LVX resistance and susceptibility in isolates from the gastroesophageal mucosa, by studying point mutations in the quinolone resistance-determining region of gyrA and gyrB genes. Sequencing of gyrA and gyrB genes (N = 120) helped to identify point mutations in 60 isolates (30 from antrum and 30 from esophagus) of five dyspeptic patients. Double (Asn87Thr and Asp91Asn) and single (Asn87Ile or Asn87Thr) mutations in the gyrA gene were identified in the esophageal mucosa. These mutations have been commonly found in the stomach. Occurrence of a single (Asn87Ile) mutation was associated with high resistance (minimum inhibitory concentration ≥ 32 μg/mL) to LVX. Only a single (Ser479Gly) mutation was found in the gyrB gene in both mucosae. One patient presented isolates with no mutations in the two genes studied. Isolates with the same mutation pattern in individual hosts revealed identical genetic profiles for these genes, confirming that isolates identified in the esophageal mucosa come from isolates colonizing the stomach. Helicobacter pylori resistance to LVX in the esophagus is related to double- and single-point mutations in gyrA and gyrB genes, such as those found in the stomach. Levofloxacin should be applied with caution, because its antibiotic effect on H. pylori is decreasing in Latin America, perhaps owing to high prescription rates.

Identification of Helicobacter and Wolinella spp. in Oral Cavity of Toy Breed Dogs With Periodontal Disease

Periodontal diseases are the most common oral cavity infectious diseases in adult dogs. We aimed in this study to identify Helicobacter and Wolinella spp. in saliva and dental plaque of dogs with periodontitis. Sixty-two small-breed pet dogs, aged more than 6 years from both sexes, were categorized into healthy and periodontitis groups. Samples from saliva and dental plaques were collected, and Helicobacter and Wolinella were identified on genus and species levels using polymerase chain reaction. Our results showed significant increase in infection rate of Wolinella spp. in periodontitis compared with healthy dogs (P = .002). Furthermore, infection rate of Helicobacter genus was significantly higher in periodontitis compared with healthy dogs (P = .007). Infection with Wolinella spp. showed higher rate than Helicobacter spp. in dogs with periodontitis. According to species-specific polymerase chain reaction results, Helicobacter felis (9.76%) was the main Helicobacter spp. in dogs with periodontitis compared with healthy dogs (P < .001). Oral cavity of pet dogs with periodontitis could be considered as an important source of Wolinella and Helicobacter spp. infections.

Multiple cag genotypes of Helicobacter pylori isolates colonize the oesophagus in individual hosts in a Venezuelan population

PURPOSE

Multiple Helicobacter pylori strains colonize and coexist in the stomach of one single patient, carrying heterogeneous distributions of cag genotypes. The oesophagus provides a niche for H. pylori colonization; however, little is known about its adaptive role.

METHODOLOGY

Using PCR for cagA, cagE and virB11 genes from cag-pathogenicity island (PAI) and Etest for antimicrobial susceptibility test, we determined cag-PAI genotypes associated with H. pylori virulence, when positive cultures were matching in both the stomach and the oesophagus (96 isolates; 8 out of 80 dyspeptic patients).

RESULTS

The stomach showed complete cag-PAI islands in 77 % of the isolates, whereas the oesophagus showed complete cag-PAI islands only in 44 % of the isolates. Expression of CagA and interleukin 8 correlated with inflammatory processes and histopathological changes in the stomach, but not in the oesophagus. Different cag-PAI profiles were found in both mucosae of an individual host, and at least one oesophagus profile corresponded to one profile identified in stomach. The antibiotic resistance profiles showed variability in the colonization by single or mixed H. pylori isolates in the gastric and oesophageal mucosa both intra- and inter-individuals.

CONCLUSION

These results demonstrate colonization with multiple H. pylori isolates in the oesophageal mucosa, like those found in the stomach of individual hosts. H. pylori was characterized by a dominant partial island, low interleukin 8 induction with lower histopathological damage and lower antibiotic resistance, suggesting that the microenvironmental changes in individual hosts select less virulent isolates in the oesophagus than in the stomach. New approaches to ensure effective eradication therapy in multi-resistant H. pylori strains must be developed.

Helicobacter pylori Infection in Rural and Urban Dyspeptic Patients from Venezuela

The goal of this work was to assess the Helicobacter pylori prevalence in a rural mestizo population and compare it to an urban population from Venezuela. The study was performed in gastric juice samples of 71 dyspeptic patients from Caracas (urban) and 39 from Tucupita (rural), in the Orinoco Delta region. Helicobacter pylori was detected by amplification of 16S rRNA, glmM, and ureA genes in 55.0% patients from urban and 87.2% from rural populations. cagA was found positive in 51% and 62% urban and rural patients, respectively. Non-H. pylori Helicobacter species were not detected in the urban population, but was found in 7.7% of patients in the rural study site. Frequency values of the 16S rRNA, glmM, and ureA genes were higher in the rural population. The odds ratio for each gene was 15.18 for 16S rRNA, 2.34 for glmM, 2.89 for ureA, and 1.53 cagA, showing significant differences except for cagA when gene frequency was compared in both populations. These results demonstrate a higher frequency of H. pylori and gastric non-H. pylori Helicobacter infection in a rural mestizo population with low hygienic standards as compared with city dwellers, representing a potential risk for the development of gastroduodenal diseases.

Helicobacter himalayensis sp. nov. isolated from gastric mucosa of Marmota himalayana

A Gram-stain-negative, microaerophilic strain, 80(YS1)T, with a spiral-shaped morphology and 1-2 sheathed flagella at each end of the cells was isolated from the gastric mucosa of Marmota himalayana, the animal reservoir of Yersinia pestis in China, on the Qinghai-Tibet Plateau. The strain grew at 30, 35 and 42 °C, but not at 25 °C. Growth was in the form of a thinly spreading film on brain heart infusion agar containing 8 % sheep blood under microaerobic conditions. The strain did not hydrolyse urea or hippurate, and did not grow on media containing 1 % glycine. It reduced nitrate to nitrite, and was catalase- and alkaline-phosphatase-positive, susceptible to nalidixic acid and resistant to cefalotin. It was positive for genus-specific PCR for the genus Helicobacter, but could not be classified to any recognized species according biochemical tests results. Therefore, a phylogenetic study based on 16S rRNA, 23S rRNA, 60 kDa heat-shock protein (hsp60) and gyrase subunit B (gyrB) genes was conducted. The 16S rRNA gene sequence (1468 bp) analysis showed that strain 80(YS1)T was most closely related to Helicobacter marmotae (96.7 % similarity). The 23S rRNA gene sequence (2879 bp) analysis showed that the strain was most closely related to Helicobacter canis (96 % similarity). The complete gyrB gene sequence (2325 bp) analysis showed that it was related phylogenetically to Helicobacter cinaedi (79.4 % similarity) and H. marmotae (79.1 % similarity). Analysis of the partial sequence of the hsp60 gene of strain 80(YS1)T showed closest similarity to the sequences of Helicobacter equorum (82 %) and H. cinaedi (81 %), respectively. However, there was no hsp60 sequence of H. marmotae available for analysis. The data of morphological, biochemical and phylogenetic characteristics all supported that this strain represents a novel species. The name Helicobacter himalayensis sp. nov. is proposed for this novel species with the type strain 80(YS1)T ( = CGMCC 1.12864T = DSM 28742T).

Low occurrence of Helicobacter DNA in tropical wild birds, Venezuela

Enteric Helicobacter species (Helicobacter pullorum, Helicobacter pametensis, Helicobacter canadensis, Helicobacter anseris, and Helicobacter brantae) have been found in birds from temperate latitudes. We evaluated the occurrence of Helicobacter spp. in terrestrial wild birds from Venezuela. A fragment of 16S rRNA gene was amplified by PCR with Helicobacter genus-specific primers. Helicobacter spp. were detected in four of 80 fecal and in three of 42 intestinal tissue samples. Analyses of 16S and 23S rRNA gene sequences confirm for the first time the presence of Helicobacter in tropical terrestrial wild birds. However, the occurrence of Helicobacter was low, suggesting these bacteria may be uncommon in the populations we studied.

Heterogeneity of cag genotypes of Helicobacter pylori in the esophageal mucosa of dyspeptic patients and its relation to histopathological outcomes

BACKGROUND

A high prevalence of Helicobacter pylori in the esophageal mucosa of dyspeptic Venezuelan patients has been reported. We aimed to assess the genetic composition of the cag genotypes of H. pylori and its relation to histopathological outcomes in the gastroesophageal mucosa.

METHODS

The presence of cagA, cagE, and virB11 cag pathogenicity island (PAI) genes was detected by PCR in 80 of 150 H. pylori-positive dyspeptic patients in both mucosae. Alterations of the gastroesophageal mucosa were assessed by histological techniques.

RESULTS

The frequency of intact, partial, and deleted cag-PAI genes in the stomach of dyspeptic patients was found to be 57.5%, 21.3%, and 21.3%, respectively, whereas in the esophagus, frequencies were 33.8%, 33.8%, and 32.5% respectively. The genetic composition in the stomach was 57.5% cagA-positive, 20.0% cagA-negative, 75.0% cagE, and 77.5% virB11, whereas in the esophagus the distribution was 36.3% cagA-positive, 30.0% cagA-negative, 61.3% cagE, and 63.8% virB11. The gene with the largest difference between the two mucosae was cagA, with 58.8% in the stomach and 37.5% in the esophagus; cagE and virB11 were less variable. The correlation among single and/or mixed cag genotypes with histopathological outcomes in both mucosae from the same patient was higher for intact single cag-PAI genotypes, showing severe alterations.

CONCLUSIONS

H. pylori may coexist in similar proportions without dominance of one cag genotype, suggesting a heterogeneous distribution in the esophagus. The cagE and virB11 genes can be used as markers of cag-PAI in the esophagus. The single cag-PAI genotype in both mucosae confers an increased risk of developing histological damage.

Description of Helicobacter valdiviensis sp. nov., an Epsilonproteobacteria isolated from wild bird faecal samples

Two Gram-stain-negative, gently curved rod-shaped isolates (WBE14T and WBE19), recovered from wild bird faecal samples in the city of Valdivia (Southern Chile) were subjected to a polyphasic taxonomic study. Results of a genus-specific PCR indicated that these isolates belonged to the genus Helicobacter . This was further confirmed by a phylogenetic analyses based on the 16S rRNA, 60 kDa heat-shock protein (cpn60) and gyrase subunit B (gyrB) genes, where both strains formed a novel phylogenetic line within this genus. The 16S rRNA gene sequence similarity of strain WBE14T to the type strains of all other species of the genus Helicobacter examined ranged from 89.4 to 97.0 %; Helicobacter brantae and Helicobacter pametensis were the most closely related species. However, on the basis of the protein-coding genes Helicobacter pullorum and Helicobacter canadensis are the most closely related species. These data, together with their different morphological and biochemical characteristics, revealed that these strains represent a novel species, for which the name Helicobacter valdiviensis sp. nov. is proposed, with the type strain WBE14T ( = CECT 8410T = LMG 27920T).

Application of stool-PCR for the diagnosis of Helicobacter pylori from stool in Nigeria- a pilot study

There are various methods for detection of Helicobacter pylori and the gold standard for non-invasive detection is the urea breath test (UBT). The aim of the study is therefore to detect H. pylori from the stool of patients with dyspepsia by PCR and compare results obtained with UBT. A total of 97 stool samples from patients presenting with dyspeptic symptoms in Lagos University Teaching Hospital (LUTH) were screened for urea breath test (UBT) and the presence of H. pylori DNA using stool-PCR. Out of 97 stool samples analysed, 38 (39.2%) were positive for Helicobacter spp. and 20 (20.6%) positive for H. pylori by PCR, through amplification of 16S rRNA and glmMgenes respectively. Of the 20 positive by glmM gene, the cagAgene was detected in 8 (40%) samples, while 47 (48.5%) out of 97 stool samples were positive for H. pylori by UBT. The sensitivity and specificity of the glmM gene compared with UBT as the gold standard is 42.6% and 100% respectively. The positive predictive value (PPV) was 100% while the negative predictive value (NPV) was 60%.The method may be useful for detecting H. pylori from stool amongst children especially where most hospitals lack endoscope for children although the method is expensive.

High frequency of Helicobacter pylori in the esophageal mucosa of dyspeptic patients and its possible association with histopathological alterations

BACKGROUND

Helicobacter pylori gastric colonization is known to be high in symptomatic subjects. However, only a few reports on the presence of H. pylori in the esophageal mucosa have been published. The aim of this study was to assess the frequency of H. pylori in the esophagus of dyspeptic patients and its association with histopathology.

METHODS

The presence of H. pylori in the gastroesophageal mucosa was detected by fluorescence in situ hybridization (FISH) and PCR analysis of DNA extracted from gastric and esophageal biopsies of 82 symptomatic patients, using genus- and species-specific PCR primers. Alterations in the gastroesophageal mucosa were assessed by conventional histological techniques.

RESULTS

H. pylori in the stomach was detected by PCR and FISH, respectively, in 61% (n=43) and 90% (n=63) of dyspeptic patients, and in the esophagus in 70% (n=44) and 73% (n=46). The prevalence of cagA-positive strains by PCR varied from 50% (n=35) in the gastric mucosa to 65% (n=41) in the esophageal mucosa. By combining the results of both methods, H. pylori was present in the gastroesophageal mucosa in 86% (n=68) of patients. The association of the presence of bacteria, including H. pylori, in the esophageal mucosa with histopathological alterations was statistically significant between microabscesses and bacteria (r=0.656, p<0.0001) and PCR detection and pseudogoblet cells (r=0.25, p<0.047).

CONCLUSIONS

This is the first report of the occurrence of H. pylori in the esophageal mucosa from dyspeptic Venezuelan patients. These results demonstrate the high prevalence of H. pylori in the esophagus, and its presence was correlated with signs of inflammation.

Prevalence of non Helicobacter pylori species in patients presenting with dyspepsia

BACKGROUND

Helicobacter species associated with human infection include Helicobacter pylori, Helicobacter heilmannii and Helicobacter felis among others. In this study we determined the prevalence of H. pylori and non-Helicobacter pylori organisms H. felis and H. heilmannii and analyzed the association between coinfection with these organisms and gastric pathology in patients presenting with dyspepsia. Biopsy specimens were obtained from patients with dyspepsia on esophagogastroduodenoscopy (EGD) for rapid urease test, histology and PCR examination for Helicobacter genus specific 16S rDNA, H. pylori phosphoglucosamine mutase (glmM) and urease B (ureB) gene of H. heilmannii and H. felis. Sequencing of PCR products of H. heilmannii and H. felis was done.

RESULTS

Two hundred-fifty patients with dyspepsia were enrolled in the study. The mean age was 39 ± 12 years with males 162(65%). Twenty-six percent (66 out of 250) were exposed to cats or dogs. PCR for Helicobacter genus specific 16S rDNA was positive in 167/250 (67%), H. pylori glmM in 142/250 (57%), H. heilmannii in 17/250 (6%) and H. felis in 10/250 (4%), respectively. All the H. heilmannii and H. felis PCR positive patients were also positive for H. pylori PCR amplification. The occurrence of coinfection of H. pylori and H. heilmannii was 17(6%) and with H. felis was 10(4%), respectively. Only one out of 66 exposed to pets were positive for H. heilmannii and two for H. felis. Histopathology was carried out in 160(64%) of 250 cases. Chronic active inflammation was observed in 53(56%) (p = 0.001) of the patients with H. pylori infection alone as compared to 3(37%) (p = 0.73) coinfected with H. heilmannii and H. pylori and 3(60%) coinfected with H. felis and H. pylori (p = 0.66). Intestinal metaplasia was observed in 3(3%)(p = 1.0) of the patients with H. pylori infection alone as compared to 2(25%) (p = 0.02) coinfected with H. heilmannii and H. pylori and 1(20%) coinfected with H. felis and H. pylori (p = 0.15).

CONCLUSION

The prevalence of H. heilmannii and H. felis was low in our patients with dyspepsia. Exposure to pets did not increase the risk of H. heilmannii or H. felis infection. The coinfection of H. pylori with H. heilmannii was seen associated with intestinal metaplasia, however this need further confirmation.

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.

Did transmission of Helicobacter pylori from humans cause a disease outbreak in a colony of Stripe-faced Dunnarts (Sminthopsis macroura)?

Since the discovery that Helicobacter pylori causes a range of pathologies in the stomachs of infected humans, it has become apparent that Helicobacters are found in a diverse range of animal species where they are frequently associated with disease. In 2003 and 2004, there were two outbreaks of increased mortality associated with gastric bleeding and weight-loss in a captive colony of the Australian marsupial, the Stripe-faced Dunnart (Sminthopsis macroura). The presence of gastric pathology led to an investigation of potential Helicobacter pathogenesis in these animals. Histological examination revealed the presence of gastritis, and PCR analysis confirmed the presence of Helicobacter infection in the stomachs of these marsupials. Surprisingly, sequencing of 16S rRNA from these bacteria identified the species as H. pylori and PCR confirmed the strain to be positive for the important pathogenesis factor, cagA. We therefore describe, for the first time, an apparent reverse zoonotic infection of Stripe-faced Dunnarts with H. pylori. Already prone to pathological effects of stress (as experienced during breeding season), concomitant H. pylori infection appears to be a possible essential but not sufficient co-factor in prototypic gastric bleeding and weight loss in these marsupials. The Stripe-faced Dunnart could represent a new model for investigating Helicobacter-driven gastric pathology. Infections from their human handlers, specifically of H. pylori, may be a potential risk to captive colonies of marsupials.

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.

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.

Genetic characterization and epidemiology of Helicobacters in non-domestic animals

BACKGROUND

Novel helicobacter infections and associated disease are being recognized with increasing frequency in animals and people. Yet, the pervasiveness of infection in distantly related animal taxa, genetic diversity of helicobacters, and their transmissability are not known.

AIM

To better understand the ecology of helicobacters, we did a PCR survey and epidemiologic analysis of 154 captive or wild vertebrate taxa originating from 6 continents.

MATERIALS AND METHODS

One hundred twenty nine helicobacter 16s rRNA gene segments were amplified by PCR and sequenced from ninety-three mammalian, reptilian, avian, or amphibian host species. Prevalence estimates were generated, and univariate logistic regression analyses were used to explore relationships between infection status and the health and characteristics of the 220 individual animals.

RESULTS

One hundred and nineteen novel helicobacter DNA sequences were found. No significant relationship between infection and host health was found; however, multi-infection or infections with particular genotypes were associated with mild clinical signs. Phylogenetic and genetic comparisons of helicobacters suggested prolonged co-adaptation and niche-associated divergence as well as periodic inter-species transmission.

CONCLUSION

The genus Helicobacter should accordingly be viewed as a collection of hundreds of organisms that have colonized most tetrapod taxa and have the potential to expand into new hosts as contact among animals and between animals and people increases.

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.

Association between entero-hepatic Helicobacter species and Crohn's disease: a prospective cross-sectional study

BACKGROUND

The pathogenesis of Crohn's disease (CD) involved microbial factors. Some Helicobacter species, the so-called entero-hepatic Helicobacters (EHH), can naturally colonize the intestinal surface and have been detected in humans. Aim To look for an association between CD and the presence of EHH DNA in intestinal biopsies.

METHODS

Two groups of patients were included prospectively in a multicentre cross-sectional study: CD patients with an endoscopic post-operative recurrence within 2 years following a surgical resection and controls screened for colorectal polyps or cancer. Intestinal biopsies were taken for Helicobacter culture and Helicobacter 16S DNA detection. If positive, the EHH species were identified with specific PCRs, sequencing and denaturing gradient gel electrophoresis.

RESULTS

In the 165 included patients (73 CD and 92 controls), Helicobacter cultures were negative. PCR was positive in 44% of CD and 47% of controls. After age-adjustment, CD was significantly associated with EHH in intestinal biopsies (OR = 2.58; 95%CI: 1.04-6.67). All EHH species detected were identified as Helicobacter pullorum and the closely related species Helicobacter canadensis.

CONCLUSION

Crohn's disease is associated with the presence of EHH species DNA in intestinal biopsies after adjustment for age. Whether these species play a role in the pathophysiology of CD remains to be determined.

Laboratory appraisal of optimal gaseous conditions for growth of zoonotic Helicobacter felis ATCC 49179

An attempt was made to assess the hitherto undescribed optimal gaseous conditions for growth of zoonotic Helicobacter felis, focusing on the ratio of spiral-forms amongst the whole cells examined. The largest mean colony diameter was obtained under the gaseous condition of O(2) 12% and CO(2) 10%. In analyzing the five day old colonies, the highest percentage of spiral forms (85.5%) was observed under the condition of O(2) 18% and CO(2) 5%. In contrast, the lowest percentage of spiral forms (2.3%) was demonstrated under the condition of O(2) 1% and CO(2) 10%. The condition of O(2) 12% and CO(2) 10% was concluded to be optimal for obtaining cells with the largest colony sizes, although colonies proliferated under such conditions definitely contain many more coccoid cells than spiral forms. In culturing H. felis strains, optimal gaseous conditions should be employed according to the purposes or preferences of study designs.

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

The aim of this study was to determine whether there is an association between Helicobacter spp. infection of the feline stomach and the presence of gastric lesions and epithelial proliferation within the mucosa of this tissue. The study included 23 pet cats of both sexes and of varied age and breed. Eighteen of these animals were clinically normal and five had a history of chronic vomiting. Samples of the mucosa of the pyloric antrum, corpus and fundus were collected by gastroscopy. The presence of Helicobacter spp. was confirmed by polymerase chain reaction (PCR) or Warthin-Starry (WS) staining and the species of Helicobacter was determined by PCR. Mucosal lesions were evaluated by examination of sections stained by haematoxylin and eosin (HE) and epithelial proliferation was determined by enumerating nucleolar organizer regions (AgNOR). In 20 (87%) cats the presence of Helicobacter spp. was confirmed by both PCR and WS. There was no significant difference in colonization density between the different gastric regions. H. heilmannii was the most frequently identified species (17 of 20 cats), and H. felis was only identified in co-infection (two of 17 cats). One sample that was PCR positive to the genus level for Helicobacter spp. was negative for the four individual species reactions. Histological changes in the lamina propria included mild mononuclear inflammatory infiltration, the presence of lymphoid follicles, fibrosis and glandular degeneration. These changes were most severe in the pyloric antrum. There was significant association between infection with gastric Helicobacter spp. and the presence of lymphoid follicles (P=0.03), and between infection and epithelial proliferation in the antrum (P<0.01), corpus (P<0.001) and fundus (P<0.001).

Evaluation of 16S rRNA gene-based PCR assays for genus-level identification of Helicobacter species

The inclusivity, exclusivity, and detection limit of six 16S rRNA gene-based Helicobacter genus-specific PCR assays were examined. Five out of six assays were 100% inclusive, but the tests varied considerably in their exclusivity (9.1 to 95.5%). The clinical detection limit varied between 10(3) and 1 viable bacterial cell per reaction mixture.

Non-pylori Helicobacteraceae in the upper digestive tract of asymptomatic Venezuelan subjects: detection of Helicobacter cetorum-like and Candidatus Wolinella africanus-like DNA

BACKGROUND

The spectrum of human non-pylori Helicobacter infections is expanding, with species such as H. heilmannii and H. felis occasionally being associated with gastritis. However, the existence of non-pylori Helicobacter colonization in asymptomatic subjects has not been evaluated. The aim of this study was to investigate whether Helicobacter species other than pylori are present in the upper digestive tract of asymptomatic human subjects.

MATERIALS AND METHODS

A Helicobacteraceae-specific semi-nested polymerase chain reaction (PCR) assay was used to detect Helicobacter-like organisms in the upper digestive tract of 91 Venezuelan volunteers (aged 18-68 years, 41 females, 50 males). Species were identified by denaturing gradient gel electrophoresis analysis and sequencing of the PCR products.

RESULTS

We detected DNA sharing 99-100% sequence identity in over 300-400 bp with the 16S rRNA genes of H. pylori, H. cetorum, and Candidatus Wolinella africanus in 76%, 16%, and 15% of the subjects, respectively. Multiple colonization was documented in 10% of the subjects: H. cetorum and Candidatus W. africanus (4%), H. pylori and Candidatus W. africanus (4%), and H. pylori and H. cetorum (2%).

CONCLUSIONS

Our results suggest that non-pylori Helicobacteraceae colonization is relatively common in the Venezuelan asymptomatic population. This is the first report documenting the presence of H. cetorum DNA in the human upper digestive tract, and the second report of the recently discovered Candidatus W. africanus.

Detection of Helicobacter-like DNA in the gastric mucosa of Thoroughbred horses

AIMS

To assess the presence of Helicobacter DNA in the gastric mucosa Thoroughbred horses.

METHODS AND RESULTS

Squamous and glandular mucosa samples were collected from 20 Thoroughbreds. None of these horses had shown any clinical symptoms of gastrointestinal disease. Necropsy tissues were analysed using histopathological techniques and a Helicobacter genus-specific PCR assay followed by sequencing of the amplicons. Seven horses were diagnosed with gastric ulceration, five with gastritis and six with both pathologies. Only two horses had a healthy gastric mucosa. Helicobacter-like DNA was detected in two out of seven horses with gastric ulcers, three out of five horses with gastritis, five out of six horses with both pathologies and one horse with normal gastric mucosa. The sequences of 1195 and 1237 bp fragments of the 16S rRNA gene shared 99% identity with the Helicobacter pylori 16S rRNA gene. However, all the samples were negative when tested with H. pylori-specific PCR assays targeting the cagA and glmM genes.

CONCLUSIONS

The Helicobacter genus might colonize the gastric mucosa of horses.

SIGNIFICANCE AND IMPACT OF THE STUDY

This is the first report of Helicobacter-like DNA in the gastric mucosa of horses and the pathogenic potential of these organisms requires further investigation.

Use of HP selective medium to detect Helicobacter pylori associated with other enteric bacteria in seawater and marine molluscs

AIMS

This project investigated the utility of HP selective medium to isolate H. pylori cells from seawater and from marine molluscs.

METHODS AND RESULTS

Nested-PCR was performed to reveal the presence of Helicobacter genus. All samples were cultured in HP selective medium and 16 cultures were initially selected as putative Helicobacter. Helicobacter spp. DNA were detected in 9/16 cultures and three of them had 99-100% homology to H. pylori based on 16S RNA gene sequence. Helicobacter pylori isolation was unsuccessful. On the basis of 16S RNA gene sequences the contaminating organisms were shown to be Proteus mirabilis and Vibrio cholerae.

CONCLUSIONS

These results indicate the coexistence of three predominant bacterial genera in the cultures and that HP selective medium can grow other enteric bacteria besides Helicobacter. Additional assays will improve the HP selective medium formulation for marine samples avoiding P. mirabilis and V. cholerae interferents.

SIGNIFICANCE AND IMPACT OF THE STUDY

This work shows the effectiveness of the selective HP medium for the Helicobacter culture from marine samples.

Helicobacter equorum sp. nov., a urease-negative Helicobacter species isolated from horse faeces

Gram-negative, curved, motile bacteria (strains EqF1T and EqF2) were isolated from faecal samples from two clinically healthy horses. Both strains possessed a single, monopolar, sheathed flagellum and were urease-negative. The novel strains grew at 37 °C under microaerobic conditions and were positive for oxidase, catalase and alkaline phosphatase activities. The isolates reduced nitrate to nitrite, but γ-glutamyl transpeptidase activity was not detected. The novel isolates did not grow at 42 °C or on media containing 1 % glycine. They were resistant to cephalotin and nalidixic acid and susceptible to metronidazole. Analysis of the 16S and 23S rRNA gene sequences of the two novel strains identified them as representing a single species within the genus Helicobacter. In terms of 16S rRNA gene sequence similarity, Helicobacter pullorum and Helicobacter canadensis were the most closely related species (98 % similarity). 23S rRNA gene sequence analysis also classified strains EqF1T and EqF2 within the enterohepatic division of the genus Helicobacter, but only 94 % similarity was detected with H. pullorum and H. canadensis, which are helicobacters with unsheathed flagella. The most closely related species in terms of 23S rRNA gene sequence similarity was Helicobacter canis (95 %). Numerical analysis of whole-cell protein extracts by SDS-PAGE was performed and the novel isolates were clearly differentiated from H. pullorum, H. canadensis, H. canis and other species of the genus Helicobacter. This finding was also confirmed by sequence analysis of the hsp60 gene. On the basis of these genetic, biochemical and protein data, the isolates are classified as representing a novel species, for which the name Helicobacter equorum sp. nov. is proposed (type strain EqF1T=LMG 23362T=CCUG 52199T).

Peptic ulcer disease associated with Helicobacter felis in a dog owner

The aim of this study was to investigate the identity of the Helicobacter heilmannii-like bacteria found in the stomach of a human patient suffering from stomach ulcers and her asymptomatic pet dog. An elderly woman was referred for gastroscopy because of right hypochondrial pain, nausea, anorexia and vomiting. Gastric ulcers were observed and histology revealed the presence of multiple H. heilmannii-like bacteria. Multiplex polymerase chain reaction (PCR) identified the bacteria as H. felis. Her pet dog was also examined gastroscopically. Only mild gastric lesions were found but PCR showed the presence of H. felis as well as H. bizzozeronii and Candidatus H. heilmannii. This report associates H. felis infection in humans with severe gastric ulceration. Moreover, the suggestion can be made that the patient contracted H. felis from her dog.

Prevalence of Helicobacter equorum in faecal samples from horses and humans

Recently, a new enterohepatic Helicobacter species, H. equorum, was isolated from faecal samples of two clinically healthy horses. At the onset of this study, nothing was known about the prevalence of this organism in horses, nor was there any information available on the possible zoonotic character of this agent. This study aimed to determine the prevalence of H. equorum in faecal samples from equine and human origin. Therefore, faecal samples of 120 healthy privately owned horses, 227 healthy riding-school horses and 239 hospitalised horses were screened for H. equorum-DNA by means of a PCR amplifying a 1074-bp fragment of the 23S rRNA gene with primers specific for H. equorum. The vast majority of the hospitalised horses were under treatment with an antimicrobial agent at the moment of sampling, while the other horses had not been treated with an antimicrobial agent in the 14 days preceding the sampling. Stool samples of 531 humans suffering from gastro-intestinal disease and 100 clinically healthy humans were likewise examined. H. equorum-DNA was demonstrated in faeces from 0.8% of the privately owned horses, 3.1% of the riding-school horses and 7.9% of the hospitalised horses. The prevalence of H. equorum was significantly higher in hospitalised than in healthy, privately owned horses (P=0.02). H. equorum-DNA was not detected in human samples. These results indicate that the prevalence of H. equorum in horses may be influenced by the health status of the investigated horse population and/or by antimicrobial treatment. We may additionally assume that this micro-organism does not commonly infect humans.

Relationship between the severity of hepatitis C virus-related liver disease and the presence of Helicobacter species in the liver: A prospective study

AIM: To determine the presence of Helicobacter species DNA in the liver of chronic hepatitis C (CHC) patients with and without cirrhosis as compared to controls, and to identify the bacterial species involved.

METHODS: Seventy-nine consecutive patients (HBV and HIV negative) with a liver sample obtained after liver biopsy or hepatic resection were studied: 41 with CHC without cirrhosis, 12 with CHC and cirrhosis, and 26 controls (HCV negative). Polymerase chain reactions (PCRs) targeting Helicobacter 16S rDNA and species-specific were performed on DNA extracted from the liver. A gastric infection with H pylori was determined by serology and confirmed by ¹³C-urea breath test.

RESULTS: Overall, Helicobacter 16S rDNA was found in 16 patients (20.2%). Although positive cases tended to be higher in CHC patients with cirrhosis (41.6%) than in those without cirrhosis (17.0%) or in controls (15.4%), the difference was not statistically significant (P = 0.08). H pylori-like DNA was identified in 12 cases and H. pullorum DNA in 2, while 2 cases remained unidenti-fied. Gastric infection with H pylori was found in only 2 of these patients.

CONCLUSION: Our results do not confirm the associ-ation of Helicobacter species DNA in the liver of CHC patients with advanced liver disease. The lack of correlation between positive H pylori serology and the presence of H pylori-like DNA in the liver may indicate the presence of a variant of this species.

Detection ofHelicobacter pyloriDNA in peripheral blood from patients with peptic ulcer or gastritis

Cases of Helicobacter bacteremia have been reported from time to time. Helicobacter pylori is the most important representative of Helicobacterium, yet whether it can result in bacteremia has rarely been studied. In this study, we examined H. pylori DNA in peripheral blood and gastric mucosa of patients with peptic ulcer or chronic gastritis by polymerase chain reaction (PCR). We found H. pylori DNA in 15 of 20 gastric samples, and 9 of these specimens were positive for H. pylori culture. H. pylori DNA amplified by PCR was positive in the peripheral blood of three patients, who all had duodenal ulcers. Gastric biopsy specimens from these three patients were all positive for H. pylori genes and H. pylori was isolated from these specimens. After the 16S rRNA gene sequences of three specimens from the same patient were obtained, we found that they were identical, which suggested that they are the same strain. Our findings suggest that H. pylori exists not only in gastric mucosa but also in peripheral blood, and it is possible that H. pylori can result in bacteremia.

Helicobacter cynogastricus sp. nov., isolated from the canine gastric mucosa

A Gram-negative, microaerophilic helical rod, isolated from the gastric mucosa of a dog and designated strain JKM4(T), was subjected to a polyphasic taxonomic study. The tightly coiled organism, measuring 10-18 mum long and up to 1 mum wide, was motile by means of multiple sheathed flagella located at both ends of the cell and by a periplasmic fibril running along the external side of the helix. Strain JKM4(T) grew preferably on biphasic culture plates or on very moist agar. Coccoid forms predominated in cultures older than 4 days as well as in growth obtained on dry agar plates. The strain grew at 30 and 37 degrees C, but not at 25 or 42 degrees C and exhibited urease, oxidase and catalase activities. On the basis of 16S rRNA gene sequence analysis, the novel isolate was identified as a member of the genus Helicobacter and showed > 97 % similarity to Helicobacter felis, Helicobacter bizzozeronii and Helicobacter salomonis, three species previously isolated from the canine gastric mucosa. Protein profiling of strain JKM4(T) using SDS-PAGE revealed a pattern different from those of other Helicobacter species of mammalian gastric origin and from Helicobacter canis. Additionally, the urease gene sequence of strain JKM4(T) was different from those of urease genes of H. felis, H. bizzozeronii, H. salomonis and "Candidatus Helicobacter heilmannii". It is thus proposed that strain JKM4(T) (=LMG 23188(T)) represents a novel species within this genus, Helicobacter cynogastricus sp. nov.

Incidence of Helicobacter felis and the effect of coinfection with Helicobacter pylori on the gastric mucosa in the African population

Helicobacter pylori and Helicobacter felis are two of the Helicobacter spp. that infect humans. H. pylori has been linked to significant gastric pathology. Coinfection with Helicobacter spp. may influence infectious burden, pathogenesis, and antibiotic resistance; however, this has not been studied. The aims of this study were to identify the incidence of H. felis and to analyze the effects of coinfection with both organisms on gastric pathology in a well-characterized South African population. Biopsy samples from the gastric corpora and antra of volunteers (n = 90) were subjected to histological examination and PCR for the identification of H. pylori and H. felis. We further investigated the effect of global strain type on the occurrence of precursor lesions by assigning nucleotide sequences derived from PCR amplification of three genes to global groupings (ancestral Africa1, ancestral Africa2, ancestral Europe, ancestral Asia, and mixed). H. pylori was detected in 75 (83.3%), H. felis in 23 (25.6%), and coinfection in 21 (23.3%) of the volunteers by PCR. H. felis was randomly distributed among adults and children but clustered within families, suggesting intrafamilial transmission. Analysis of histopathology scores revealed no differences in atrophy, activity, and helicobacter density between H. felis-positive and H. felis-negative volunteers. H. pylori substrains common to southern Africa showed no differences in inflammation or atrophy scores. The incidences of H. felis and coinfection with H. pylori in the African population are high. H. felis infection, however, does not influence specific gastric pathology in this population.

Helicobacter spp. from captive bottlenose dolphins (Tursiops spp.) and polar bears (Ursus maritimus)

The gastric fluid of six bottlenose dolphins and the faeces of four polar bears from the same oceanarium were examined for the presence of Helicobacter. As detected by PCR, all dolphins and 8/12 samples collected from polar bears were positive for Helicobacter. Novel sequence types were identified in samples collected from these animals of which several were unique to either the dolphins or the polar bears. At least one sequence type was, however, detected in both animal taxa. In addition, a sequence type from a dolphin shared a 98.2-100% identity to sequences from other Helicobacter species from harp seals, sea otters and sea lions. This study reports on the occurrence of novel Helicobacter sequence types in polar bears and dolphins and demonstrates the broad-host range of some species within these animals.

Identification of non-Helicobacter pylori spiral organisms in gastric samples from humans, dogs, and cats

Tightly coiled bacteria are a rare cause of gastric pathology in humans and represent a mixture of species for which a zoonotic origin is suspected. Similar organisms are common inhabitants of the gastric mucosae of carnivores and pigs. It was the goal of the present study to determine the actual occurrence of each individual Helicobacter species in human, canine, and feline stomachs in order to better understand the possible zoonotic significance. Gastric biopsy samples from humans with histological evidence of non-Helicobacter pylori spiral bacteria (n = 123) and samples from the gastric antrum, corpus, and cardia from dogs (n = 110) and cats (n = 43) were subjected to a multiplex PCR, enabling the identification of Helicobacter felis, Helicobacter bizzozeronii, Helicobacter salomonis, and "Candidatus Helicobacter suis." A PCR for detecting H. pylori was applied to all human samples. Single infections with "Candidatus Helicobacter suis," H. felis, H. bizzozeronii, H. salomonis, a hitherto unknown genotype of a non-H. pylori spiral organism (Helicobacter-like organism 135 [HLO135]), and H. pylori were identified in 30.9%, 8.9%, 2.4%, 11.4%, 7.3%, and 8.9% of the human biopsy samples, respectively. Mixed infections (16.3%) with two or even three of these were also found. In the canine stomach, H. bizzozeronii (70.0%) was encountered as the main spiral organism, while H. felis (62.7%) and HLO135 (67.4%) were the predominant Helicobacter species found in the feline gastric mucosa. Although the majority of human non-H. pylori organisms are Helicobacter species naturally occurring in the stomachs of pigs, cats, and dogs, the frequent identification of H. salomonis in human gastric biopsy samples is in contrast to its rare identification in pet carnivore samples, urging us to suspect other sources of infection.