RESUMO
This research aims to compare the culturing conditions for enterohepatic Helicobacter, evaluating culture media, incubation atmosphere and susceptibility to antimicrobials used to generate selective conditions. Four common media for the closely related genus Campylobacter (Columbia, Bolton, Brucella and CCDA agar), as well as the need for hydrogen in the microaerobic incubation atmosphere, were evaluated. Serial dilutions of 13 strains belonging to six species (H. apodemus, H. bilis, H. canicola, H. canis, H. equorum and Helicobacter sp.) were inoculated in each media and incubated at 37°C for 48 to 96 h using CampyGen (OXOID) and gaseous exchange (including hydrogen) in parallel. Columbia or Brucella agars were the most appropriate for culturing EHH (P < 0·05). However, there was no significant difference between the atmospheres evaluated (P = 0·13). In addition, minimal inhibitory concentration for six antibiotics showed that all isolates were resistant to trimethoprim, whereas for the rest of the antibiotics (cephalothin, cefoperazone, cefsulodin, teicoplanin and vancomycin) the inhibition range was between 8 and 64 µg ml- 1 . Our findings suggest that Columbia or Brucella media, regardless of the use of hydrogen, can be used for the EHH isolation. In addition, the concentration of antibiotics included in commercial campylobacteria supplements is suitable for EHH species recovery. SIGNIFICANCE AND IMPACT OF THE STUDY: Enterohepatic Helicobacter (EHH) infections have been associated with several diseases in humans such as acute gastroenteritis, inflammatory bowel disease and hepatobiliary diseases. Although they are frequently detected in clinical samples by molecular methods, only occasionally they are isolated using culture conditions described for the taxonomic related pathogen Campylobacter sp. This is because the optimal conditions for the isolation of EHH have not yet been described, which results in an underestimation of the prevalence and clinical importance of these emerging pathogens. Therefore, this study provides insight for culturing EHH species.
Assuntos
Ágar/química , Antibacterianos/farmacologia , Meios de Cultura/química , Helicobacter/crescimento & desenvolvimento , Helicobacter/metabolismo , Campylobacter/crescimento & desenvolvimento , Gastroenterite/microbiologia , Helicobacter/classificação , Infecções por Helicobacter/tratamento farmacológico , Humanos , Testes de Sensibilidade MicrobianaRESUMO
Helicobacter pylori a gram negative bacilli is related with development of gastroduodenal disease as chronic active gastritis, peptic ulcer disease MALT type lymphomas and gastric cancer. The WHO defined H. pylori as a human carcinogen agent. Helicobacter colonizes the gastric epithelium and promotes inflammation and mucosal damage. Third part of the world's population is infected by the bacteria and many researchers consider that the mode of transmission between human being is via the fecal-oral and/or oral-oral manner. H. pylori may be identified in saliva, gastric juice, gastric biopsies and feces by different methods. The eradication of this microorganism disminished the gastrointestinal tract disease.
Assuntos
Infecções por Helicobacter/microbiologia , Helicobacter pylori , Animais , Proteínas de Bactérias/biossíntese , Técnicas Bacteriológicas , Campylobacter/classificação , Campylobacter/metabolismo , Citotoxinas/biossíntese , Enzimas/biossíntese , Gastrite/microbiologia , Helicobacter/classificação , Helicobacter/metabolismo , Infecções por Helicobacter/diagnóstico , Infecções por Helicobacter/história , Infecções por Helicobacter/transmissão , Helicobacter pylori/efeitos dos fármacos , Helicobacter pylori/isolamento & purificação , Helicobacter pylori/patogenicidade , Helicobacter pylori/fisiologia , História do Século XX , Humanos , Linfoma não Hodgkin/microbiologia , Mamíferos/microbiologia , Especificidade da Espécie , Neoplasias Gástricas/microbiologia , Úlcera Gástrica/microbiologia , VirulênciaRESUMO
A new Helicobacter species that colonizes the colonic mucosa of Wistar and Holtzman rats was isolated and characterized. This bacterium was gram negative, its cells were rod shaped with pointed ends, and its protoplasmic cylinder was entwined with periplasmic fibers. It was catalase and oxidase positive, rapidly hydrolyzed urea, and was susceptible to metronidazole and resistant to cephalothin and nalidixic acid. The new organism was microaerophilic and grew at 42 degrees C, a feature that differentiates it from two other murine intestine colonizers, Helicobacter hepaticus and Helicobacter muridarum. On the basis of 16S rRNA sequence analysis data, the new organism was identified as a Helicobacter species that is most closely related to H. hepaticus. This bacterium is named Helicobacter trogontum. The type strain is strain LRB 8581 (= ATCC 700114).