Helicobacter heilmannii related gastric ulcer in childhood

Helicobacter bizzozeronii infection in a girl with severe gastric disorders in México: case report

BACKGROUND

Gastric non-Helicobacter pylori helicobacters (NHPH) naturally colonize the stomach of animals. In humans, infection with these bacteria is associated with chronic active gastritis, peptic ulceration and MALT-lymphoma. H. bizzozeronii belongs to these NHPH and its prevalence in children is unknown.

CASE PRESENTATION

This case report describes for the first time a NHPH infection in a 20-month-old girl with severe gastric disorders in Mexico. The patient suffered from melena, epigastric pain, and bloating. Gastroscopy showed presence of a Hiatus Hill grade I, a hemorrhagic gastropathy in the fundus and gastric body, and a Forrest class III ulcer in the fundus. Histopathologic examination revealed a chronic active gastritis with presence of long, spiral-shaped bacilli in the glandular lumen. Biopsies from antrum, body and incisure were negative for presence of H. pylori by culture and PCR, while all biopsies were positive for presence of H. bizzozeronii by PCR. Most likely, infection occurred through intense contact with the family dog. The patient received a triple therapy consisting of a proton pump inhibitor, clarithromycin, and amoxicillin for 14 days, completed with sucralfate for 6 weeks, resulting in the disappearance of her complaints.

CONCLUSION

The eradication could not be confirmed, although it was suggested by clear improvement of symptoms. This case report further emphasizes the zoonotic importance of NHPH. It can be advised to routinely check for presence of both H. pylori and NHPH in human patients with gastric complains.

Helicobacter species binding to the human gastric mucosa

Helicobacter pylori infects half of the world population, being associated with several gastric disorders, such as chronic gastritis and gastric carcinoma. The Helicobacter genus also includes other gastric helicobacters, such as H. heilmannii¸ H. ailurogastricus, H. suis, H. felis, H. bizzozeronii, and H. salomonis. These gastric helicobacters colonize both the human and animal stomach. The prevalence of gastric non-Helicobacter pylori Helicobacter (NHPH) species in humans has been described as low, and the in vitro binding to the human gastric mucosa was never assessed. Herein, human gastric tissue sections were used for the evaluation of the tissue glycophenotype and for the binding of gastric NHPH strains belonging to different species. Histopathological evaluation showed that 37.5% of the patients enrolled in our cohort presented chronic gastritis, while the presence of neutrophil or eosinophilic activity (chronic active gastritis) was observed in 62.5% of the patients. The secretor phenotype was observed in 68.8% of the individuals, based on the expression of Lewis B antigen and binding of the UleX lectin. The in vitro binding assay showed that all the NHPH strains evaluated were able to bind, albeit in low frequency, to the human gastric mucosa. The H. heilmannii, H. bizzozeronii, and H. salomonis strains displayed the highest binding ability both to the gastric superficial epithelium and to the deep glands. Interestingly, we observed binding of NHPH to the gastric mucosa of individuals with severe chronic inflammation and intestinal metaplasia, suggesting that NHPH binding may not be restricted to the healthy gastric mucosa or slight chronic gastritis. Furthermore, the in vitro binding of NHPH strains was observed both in secretor and non-secretor individuals in a similar frequency. In conclusion, this study is the first report of the in vitro binding ability of gastric NHPH species to the human gastric mucosa. The results suggest that other glycans, besides the Lewis antigens, could be involved in the bacterial adhesion mechanism; however, the molecular intervenients remain unknown.

Presence of Helicobacter Species in Gastric Mucosa of Human Patients and Outcome of Helicobacter Eradication Treatment

The genus Helicobacter is composed of bacteria that colonize both the human and animal gastrointestinal tract. Helicobacter pylori infects half of the world’s population, causing various disorders, such as gastritis, duodenitis and gastric cancer. Additionally, non-Helicobacter pylori Helicobacter species (NHPH) are commonly found in the stomach of pigs, dogs and cats. Most of these species have zoonotic potential and prevalence rates of 0.2–6.0%, and have been described in human patients suffering from gastric disorders undergoing a gastric biopsy. The aim of this study was to determine the occurrence of Helicobacter spp. in the stomach of patients with gastric cancer (n = 17) and obese (n = 63) patients. Furthermore, the outcome of the Helicobacter eradication treatment and the current infection status was evaluated. Overall, based on the genus-specific PCR followed by sequencing, DNA from Helicobacter spp. was detected in 46.3% of the patients, including single infections with H. pylori in 43.8% of the patients and mixed infections with H. pylori and canine- or feline-associated H. felis in 2.5%. About 32.5% of the patients had been subjected to previous Helicobacter eradication therapy and the triple standard therapy was the most frequent scheme (42.3%). In 48.0% of the patients who received eradication treatment, bacteria were still detected, including one mixed infection. In 23.1% of the patients who reported that a subsequent test had been performed to confirm the elimination of the bacteria, Helicobacter were still detected. In conclusion, although in a smaller percentage, NHPH may also be present in the human stomach. Thus, specific NHPH screening should be included in the diagnostic routine. The continued presence of H. pylori in the stomach of patients recently subjected to eradication schemes raises questions about the efficacy of the current Helicobacter treatments.

Transmission of Helicobacter pylori between a human and two dogs: A case report

BACKGROUND

Whereas non-Helicobacter pylori helicobacters, which are frequently detected in the stomachs of dogs and cats as a source of zoonoses, have attracted considerable attention, the role of pets in H. pylori epidemiology is unclear. In our previous study, an H. pylori infection was detected in the stomach of a dog (Dog 1). Here, we investigated the H. pylori infection status in the female offspring of Dog 1 (Dog 2) and its owner within the same household.

MATERIALS AND METHODS

Biopsy specimens were obtained from the dog's owner and tested for H. pylori. DNA from gastric biopsy samples of Dog 1, gastric fluid sediment of Dog 2, and bacteria from the stomach of the owner was obtained, and Helicobacter genus- and species-specific PCRs were performed. Then, sequence analyses of the partial region of the ureAB gene were conducted.

RESULTS

Samples from both dogs and the owner reacted positively in the genus-specific PCR and negative in the Helicobacter felis-, Helicobacter bizzozeronii-, and Helicobacter heilmannii sensu stricto-specific PCRs. All three samples also reacted positively in the H. pylori-specific PCR. Sequences of the partial ureAB gene from all subjects were identical.

CONCLUSIONS

The results suggested that the two dogs and their owner were infected with an identical H. pylori strain. This report is the first to demonstrate that H. pylori can be transmitted between humans and dogs. Further studies are required to investigate the risk factors for the transmission of H. pylori between humans and dogs from the perspective of preventive epidemiology.

Adhesion of Helicobacter Species to the Human Gastric Mucosa: A Deep Look Into Glycans Role

Helicobacter species infections may be associated with the development of gastric disorders, such as gastritis, peptic ulcers, intestinal metaplasia, dysplasia and gastric carcinoma. Binding of these bacteria to the gastric mucosa occurs through the recognition of specific glycan receptors expressed by the host epithelial cells. This review addresses the state of the art knowledge on these host glycan structures and the bacterial adhesins involved in Helicobacter spp. adhesion to gastric mucosa colonization. Glycans are expressed on every cell surface and they are crucial for several biological processes, including protein folding, cell signaling and recognition, and host-pathogen interactions. Helicobacter pylori is the most predominant gastric Helicobacter species in humans. The adhesion of this bacterium to glycan epitopes present on the gastric epithelial surface is a crucial step for a successful colonization. Major adhesins essential for colonization and infection are the blood-group antigen-binding adhesin (BabA) which mediates the interaction with fucosylated H-type 1 and Lewis B glycans, and the sialic acid-binding adhesin (SabA) which recognizes the sialyl-Lewis A and X glycan antigens. Since not every H. pylori strain expresses functional BabA or SabA adhesins, other bacterial proteins are most probably also involved in this adhesion process, including LabA (LacdiNAc-binding adhesin), which binds to the LacdiNAc motif on MUC5AC mucin. Besides H. pylori, several other gastric non-Helicobacter pylori Helicobacters (NHPH), mainly associated with pigs (H. suis) and pets (H. felis, H. bizzozeronii, H. salomonis, and H. heilmannii), may also colonize the human stomach and cause gastric disease, including gastritis, peptic ulcers and mucosa-associated lymphoid tissue (MALT) lymphoma. These NHPH lack homologous to the major known adhesins involved in colonization of the human stomach. In humans, NHPH infection rate is much lower than in the natural hosts. Differences in the glycosylation profile between gastric human and animal mucins acting as glycan receptors for NHPH-associated adhesins, may be involved. The identification and characterization of the key molecules involved in the adhesion of gastric Helicobacter species to the gastric mucosa is important to understand the colonization and infection strategies displayed by different members of this genus.

Helicobacter Species Identified in Captive Sooty Mangabeys (Cercocebus atys) with Metastatic Gastric Adenocarcinoma

BACKGROUND

Of all human cancers, gastric carcinoma is the one of the leading causes of death. Helicobacter pylori is considered a major etiologic agent of this disease. Spontaneously occurring gastric carcinoma is a rare diagnosis in nonhuman primates. A 2011 case report documented a high incidence of gastric adenocarcinoma in a closed colony of captive sooty mangabeys (Cercebus atys). However, H. pylori infection was not detected in these animals.

MATERIALS AND METHODS

In this study, using archived formalin-fixed, paraffin-embedded stomach sections of these animals alternative methodologies were used to identify H. pylori and other non-H. pylori Helicobacter species. In addition, two additional cases of sooty mangabeys with metastatic gastric carcinoma are characterized.

RESULTS

Using fluorescent in situ hybridization, we identified gastric H. suis in 75% of archived and new gastric carcinoma cases. In the two newly reported cases, H. suis and a novel Helicobacter species were detected via PCR and sequence analysis of the 16S rRNA gene. H. pylori was not identified in any of the gastric carcinoma cases via FISH and/or PCR and sequence analysis of Helicobacter spp. in DNA from of available tissues.

CONCLUSIONS

This report is the first to characterize Helicobacter species infection in spontaneous gastric carcinoma with metastatic potential in nonhuman primates.

Prevalence of Coinfection with Gastric Non-Helicobacter pylori Helicobacter (NHPH) Species in Helicobacter pylori-infected Patients Suffering from Gastric Disease in Beijing, China

BACKGROUND

The Helicobacter heilmannii sensu lato (H. heilmannii s.l.) group consists of long, spiral-shaped bacteria naturally colonizing the stomach of animals. Moreover, bacteria belonging to this group have been observed in 0.2-6% of human gastric biopsy specimens, and associations have been made with the development of chronic gastritis, peptic ulceration, and gastric MALT lymphoma in humans.

MATERIALS AND METHODS

To gain insight into the prevalence of H. heilmannii s.l. infections in patients suffering from gastric disease in China, H. heilmannii s.l. species-specific PCRs were performed on DNA extracts from rapid urease test (RUT)-positive gastric biopsies from 1517 patients followed by nucleotide sequencing. At the same time, Helicobacter pylori cultivation and specific PCR was performed to assess H. pylori infection in these patients.

RESULTS

In total, H. heilmannii s.l. infection was detected in 11.87% (178/1499) of H. pylori-positive patients. The prevalence of H. suis, H. felis, H. bizzozeronii, H. heilmannii sensu stricto (s.s.), and H. salomonis in the patients was 6.94%, 2.20%, 0.13%, 0.07%, and 2.54%, respectively. Results revealed that all patients with H. heilmannii s.l. infection were co-infected with H. pylori, and some patients were co-infected with more than two different Helicobacter species.

CONCLUSIONS

Helicobacter heilmannii s.l. infections are fairly common in Chinese patients. This should be kept in mind when diagnosing the cause of gastric pathologies in patients. Helicobacter suis was shown to be by far the most prevalent H. heilmannii s.l.species.

Helicobacter heilmannii sensu lato: An overview of the infection in humans

Helicobacter heilmannii sensu lato (H. heilmannii s.l.) is a group of gastric non-Helicobacter pylori Helicobacter species that are morphologically indistinguishable from each other. H. heilmannii s.l. infect the stomach of several animals and may have zoonotic potential. Although the prevalence of these infections in humans is low, they are associated with gastric pathology, including mucosa-associated lymphoid tissue lymphoma, making them a significant health issue. Here, the taxonomy, epidemiology, microbiology, diagnosis, and treatment of these infections will be reviewed. The gastric pathology associated with H. heilmannii s.l. infections in humans will also be addressed. Finally, the features of the complete bacterial genomes available and studies on species-specific pathogenesis will be reviewed. The understanding of the mechanisms that underlie gastric disease development mediated by the different bacterial species that constitute H. heilmannii s.l. is essential for developing strategies for prevention and treatment of these infections.

Contingency nature of Helicobacter bizzozeronii oxygen-insensitive NAD(P)H-nitroreductase (HBZC1_00960) and its role in metronidazole resistance

Genomic analysis of a metronidazole resistant H. bizzozeronii strain revealed a frame length extension of the oxygen-insensitive NAD(P)H-nitroreductase HBZC1_00960 (RdxA), associated with the disruption of the C-terminal cysteine-containing conserved region (IACLXALGK). This was the result of the extension (from C8 to C9) of a simple sequence cytosine repeat (SSCR) located in the 3' of the gene. A 3' SSCR is also present in the rdxA homolog of H. heilmannii sensu stricto, but not in H. pylori. We showed that in the majority of in vitro spontaneous H. bizzozeronii metronidazole resistant mutants, the extension of the 3' SSCR of rdxA was the only mutation observed. In addition, we observed that H. bizzozeronii ΔrdxA mutant strain showed the same MIC value of metronidazole observed in the spontaneous mutants. These data indicate that loss of function mutations in rdxA and in particular the disruption of the conserved region IACLXALGK is associated with reduced susceptibility to metronidazole in H. bizzozeronii. Slipped-strand mispairing of the SSCR located in the 3' of the H. bizzozeronii rdxA appears to be the main mechanism. We also observed that H. bizzozeronii acquires resistance to metronidazole at high mutation rate, and that serial passages in vitro without selection induced an increased level of susceptibility. In conclusion, contrary to what was previously described in H. pylori, the H. bizzozeronii rdxA appears to be a contingency gene which undergoes phase variation. The contingency nature of rdxA should be carefully considered when metronidazole is used in the treatment of H. heilmannii-associated gastritis.

Clinical characteristics of Helicobacter heilmannii- versus Helicobacter pylori-associated gastritis in Chinese patients

AIM: To compare the endoscopic and histopathological characteristics of Helicobacter heilmannii (H. heilmannii)- versusHelicobacter pylori (H. pylori)-associated gastritis in Chinese patients.

METHODS: Gastric biopsy specimens from 53559 consecutive patients treated at Peking University Third Hospital from January 2003 to January 2010 were reviewed retrospectively. All cases of chronic gastritis were evaluated based on the Updated Sydney System. Endoscopic and histopathological characteristics of cases with H. heilmannii infection were compared with those with H. pylori infection.

RESULTS: There were 46 cases with H. heilmannii infection (0.1%) and 18326 cases with H. pylori infection (34.2%). Compared to H. pylori-associated gastritis, H. heilmannii-associated gastritis showed a lower bacterial density (P < 0.001), less severe mononuclear cell infiltration (P < 0.001) and neutrophil activity (P < 0.001), and endoscopic findings of H. heilmannii-associated gastritis were devoid of ulcer (P = 0.021). H. heilmannii density showed a significant correlation with neutrophil activity (P = 0.02), but not with chronic inflammation (P = 0.159). The percentages of patients with mucosal atrophy, intestinal metaplasia and intraepthelial neoplasia in the H. heilmannii-associated gastritis group were 23.9%, 21.7% and 4.3%, respectively, and there was no significant difference in the prevalence and degree of these precancerous lesions between the two groups. A case of signet-ring cell carcinoma concomitant with H. heilmannii infection was detected.

CONCLUSION: H. heilmannii-associated gastritis is uncommon and milder than H. pylori-associated gastritis. The observation that there were no significant differences between two groups in the prevalence and degree of mucosal atrophy, intestinal metaplasia and intraepthelial neoplasia suggests that H. heilmannii may be partly responsible for malignant-associated lesions just as H. pylori does. In addition, one case of signet-ring cell carcinoma concomitant with H. heilmannii infection was noted.

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.

Gastric helicobacters in domestic animals and nonhuman primates and their significance for human health. Clin Microbiol Rev. 2009;22:202-223, Table of Contents. [PMID: 19366912 DOI: 10.1128/cmr.00041-08]

Helicobacters other than Helicobacter pylori have been associated with gastritis, gastric ulcers, and gastric mucosa-associated lymphoid tissue lymphoma in humans. These very fastidious microorganisms with a typical large spiral-shaped morphology were provisionally designated "H. heilmannii," but in fact they comprise at least five different Helicobacter species, all of which are known to colonize the gastric mucosa of animals. H. suis, which has been isolated from the stomachs of pigs, is the most prevalent gastric non-H. pylori Helicobacter species in humans. Other gastric non-H. pylori helicobacters colonizing the human stomach are H. felis, H. salomonis, H. bizzozeronii, and the still-uncultivable "Candidatus Helicobacter heilmannii." These microorganisms are often detected in the stomachs of dogs and cats. "Candidatus Helicobacter bovis" is highly prevalent in the abomasums of cattle but has only occasionally been detected in the stomachs of humans. There are clear indications that gastric non-H. pylori Helicobacter infections in humans originate from animals, and it is likely that transmission to humans occurs through direct contact. Little is known about the virulence factors of these microorganisms. The recent successes with in vitro isolation of non-H. pylori helicobacters from domestic animals open new perspectives for studying these microorganisms and their interactions with the host.

The effect of Helicobacter felis and Helicobacter bizzozeronii on the gastric mucosa in Mongolian gerbils: a sequential pathological study

In contrast to Helicobacter(H.) pylori, little is known about the pathogenic mechanisms of gastric non-H. pylori Helicobacter species. Mongolian gerbils were inoculated intragastrically with H. felis or H. bizzozeronii and killed at different timepoints post-inoculation (p.i.), stomach tissue being taken for light and transmission electron microscopy (TEM) and polymerase chain reaction (PCR) analysis. Parietal cells (PCs), apoptosis, cell proliferation and nuclear factor-kappaB (NF-kappaB) activation were "visualized" immunohistochemically. Inflammation consisted of neutrophilic granulocytes, mainly in the antrum, and lymphocytic infiltrates around the limiting ridge and throughout the stomach mucosa and submucosa. From day 11 p.i. onwards, H. felis-inoculated animals showed moderate to severe loss of PCs extending from the limiting ridge into the fundus. Apoptotic cells, spiral bacteria, cell proliferation, and NF-kappaB activation were detected at the transition zone between affected and normal PCs. TEM revealed interaction of H. felis flagella with PCs and chief cells. Moreover, H. felis was seen in proximity to, and inside, necrotic cells. At 10 weeks p.i., some H. felis-infected gerbils showed complete loss of fundic glands, and mucous metaplasia of the epithelium. H. bizzozeronii, which made no flagellar contact with epithelial cells, was associated with only mild PC loss. The mechanism by which H. felis induces PC necrosis and apoptosis remains unclear. The observed flagellar contact and NF-kappaB activation may play an important role in H. felis-associated inflammation.

Acute symptomatic gastritis due to Helicobacter heilmannii

Helicobacter heilmannii is a Gram-negative spiral-shaped organism predominantly associated with zoonotic infection. Human pathology has also been described, but acute symptoms with complete resolution have been infrequently reported. We present a 50-year-old man in whom H. heilmannii gastritis presented as an acute febrile illness and was successfully treated with antibiotics and proton pump inhibitor. Epidemiology, diagnosis, and treatment of similar cases are reviewed.

Evaluation of antibiotic treatment against "Candidatus Helicobacter suis" in a mouse model

"Helicobacter heilmannii" (proposed name) type 1 colonizes the human stomach. It has been shown to be identical to "Candidatus Helicobacter suis," a Helicobacter species colonizing the stomachs of >60% of slaughter pigs. This bacterium has not been isolated in vitro until now. Antibiotic susceptibility testing of "Candidatus Helicobacter suis" has not been carried out so far. For the present study, a mouse model was adopted to evaluate the antibiotic susceptibility of this organism. Mice infected with "Candidatus Helicobacter suis" were treated with amoxicillin and omeprazole, a therapy which is used to treat H. heilmannii infections in humans. Two different isolates of "Candidatus Helicobacter suis" were tested. The excretion of bacterial DNA was assessed during treatment, using PCR on fecal samples. At the end of the experiment, 8 days after the cessation of treatment, the presence of infection was evaluated using a urease test and a PCR test on stomach samples. A marked decrease in the excretion of bacterial DNA was observed a few days after the onset of treatment, and the level remained low until the end of the experiment. A difference in susceptibility between the two "Candidatus Helicobacter suis" isolates was pointed out. The in vivo mouse model infected with "Candidatus Helicobacter suis" will be useful for further screening of potential therapeutic regimens.

In vitro antimicrobial susceptibility testing of Helicobacter felis, H. bizzozeronii, and H. salomonis

The susceptibilities of Helicobacter felis (15 strains), H. bizzozeronii (7 strains), and H. salomonis (3 strains) to 10 antimicrobial agents were investigated by determination of the MIC using the agar dilution method. No consistent differences were noticed between the different Helicobacter species, which were all highly susceptible to ampicillin, clarithromycin, tetracycline, tylosin, enrofloxacin, gentamicin, and neomycin, as demonstrated by low MICs. Higher MICs were obtained for lincomycin (up to 8 microg/ml) and spectinomycin (up to 4 microg/ml). Two H. felis strains showed a MIC of 16 microg/ml for metronidazole, suggesting acquired resistance to this antimicrobial agent.

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.

Helicobacter heilmannii gastroduodenal disease and clinical aspects in children with dyspeptic symptoms

AIM

To evaluate the occurrence and clinical characteristics of Helicobacter heilmannii infection among children presenting with dyspeptic symptoms.

METHOD

Prospective cohort study of 580 patients.

RESULTS

Of all examined dyspeptic children, 26.4% were infected with spiral-shaped organisms, and 0.9% of patients were found to be infected with spiral H. heilmannii-like organisms.

CONCLUSION

In children with dyspeptic symptoms, the possible presence of gastroduodenal disease due to H. heilmannii should be considered. Further studies are needed to clarify H. heilmannii-related gastroduodenal pathology in the paediatric population.

Helicobacter pylori and extragastric diseases -- other helicobacters

The role of Helicobacter pylori infection is explored in more and more extragastric diseases without definite proof in most of the studies, except possibly some hematologic diseases. In cardiovascular diseases, including stroke, the presence of CagA positive strains may be involved. The possible role of helicobacters in hepatobiliary diseases goes beyond that of H. pylori to involve enterohepatic helicobacters. New Helicobacter species are regularly described and molecular methods are developed to improve their detection. Helicobacter felis remains the major species to be used in animal models of Helicobacter infection.