imported>John J. Dennehy |
imported>Jignisha Patel |
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| | ==Classification== |
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| | [[Image: Tosco_Refinery.jpg]] |
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| | ===Higher order taxa=== |
| ==Diagnosis== | |
| ===Prior infection=== | |
| Detection of serum [[antibody|antibodies]] against [[H. pylori]] indicate prior infection. The probability of having positive antibody test is approximately the same as the age of the patient.<ref name="pmid2179722">{{cite journal |author=Soll AH |title=Pathogenesis of peptic ulcer and implications for therapy |journal=N. Engl. J. Med. |volume=322 |issue=13 |pages=909–16 |year=1990 |pmid=2179722 |doi=}}</ref> For example, a 50 year old male has approximately a 50% chance of having antibodies against ''H. pylori''.
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| ===Active infection===
| | Domain; Phylum; Class; Order; family [Others may be used. Use [http://www.tolweb.org/tree/ Tree of Life] link to find] |
| There is no one test that detects all patients infected with ''H. pylori''.
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| ====Non-invasive tests====
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| [[Clinical practice guideline]]s by the American Gastroenterological Association state "''[[H. pylori]]'' testing is optimally performed by a <sup>13</sup>C-urea breath test or stool antigen test."<ref name="pmid16285970">{{cite journal |author=Talley NJ |title=American Gastroenterological Association medical position statement: evaluation of dyspepsia |journal=Gastroenterology |volume=129 |issue=5 |pages=1753–5 |year=2005 |pmid=16285970 |doi=10.1053/j.gastro.2005.09.019}} [http://www.ngc.gov/summary/summary.aspx?ss=15&doc_id=8442&nbr=004711 National Guideline Clearinghouse]</ref> Details of test accuracy have been reviewed.<ref name="pmid11668141">{{cite journal |author=Logan RP, Walker MM |title=ABC of the upper gastrointestinal tract: Epidemiology and diagnosis of Helicobacter pylori infection |journal=BMJ |volume=323 |issue=7318 |pages=920–2 |year=2001 |pmid=11668141 |doi=}}</ref>
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| If a patient is taking anti-secretory therapy, the breath test may be falsely negative for 3-9 days after stopping pantoprazole. For patients on ranitidine, if they have been taking it for at least 30 days, they do not need a washout period.<ref name="pmid12643609">{{cite journal |author=Dulbecco P, Gambaro C, Bilardi C, ''et al'' |title=Impact of long-term ranitidine and pantoprazole on accuracy of [13C]urea breath test |journal=Dig. Dis. Sci. |volume=48 |issue=2 |pages=315–21 |year=2003 |pmid=12643609 |doi=}}</ref>
| | ===Species=== |
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| ====Invasive tests====
| | ''Genus species''[[Image:Example.jpg]] |
| ''[[H. pylori]]'' can be detected during esophagogastroduodenoscopy (EGD) by biopsy, culture, or rapid urease testing. | |
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| ==Treatment== | | ==Description and significance== |
| Clinical practice guidelines<ref name="pmid17608775">{{cite journal |author=Chey WD, Wong BC |title=American College of Gastroenterology guideline on the management of Helicobacter pylori infection |journal=Am. J. Gastroenterol. |volume=102 |issue=8 |pages=1808–25 |year=2007 |pmid=17608775 |doi=10.1111/j.1572-0241.2007.01393.x}}</ref> by the American College of Gastroenterology and systemical review by the UK [http://clinicalevidence.com Clinical Evidence]<ref name="pmid16135272">{{cite journal |author=Delaney B, Moayyedi P, Forman D |title=Helicobacter pylori infection |journal=Clinical evidence |volume= |issue=13 |pages=518–34 |year=2005 |pmid=16135272 |doi=|url=http://clinicalevidence.bmj.com/ceweb/conditions/dsd/0406/0406.jsp}}</ref> guide treatment. The recommendations conflict on treating non-ulcer dyspepsia.
| | Describe the appearance, habitat, etc. of the organism, and why it is important enough to have its genome sequenced. Describe how and where it was isolated. |
| | Include a picture or two (with sources) if you can find them. |
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| Regarding which patient to treat:
| | ==Genome structure== |
| * Patients with duodenal or gastric ulcer, non-ulcer dyspepsia, people with uninvestigated dyspepsia.<ref name="pmid16135272"/>
| | Describe the size and content of the genome. How many chromosomes? Circular or linear? Other interesting features? What is known about its sequence? |
| * "Testing is uncertain among patients with functional dyspepsia, gastroesophageal reflux disease (GERD), patients taking nonsteroidal antiinflammatory drugs, with iron deficiency anemia, or who are at risk of developing gastric cancer".<ref name="pmid17608775"/> A subsequent [[randomized controlled trial]] showed benefit of eradication to prevent gastric cancer in a high risk region.<ref name="pmid14722144">{{cite journal |author=Wong BC, Lam SK, Wong WM, ''et al'' |title=Helicobacter pylori eradication to prevent gastric cancer in a high-risk region of China: a randomized controlled trial |journal=JAMA |volume=291 |issue=2 |pages=187–94 |year=2004 |pmid=14722144 |doi=10.1001/jama.291.2.187}}</ref> Regarding gastritis and gastric erosions, patients with antral predominant gastritis are more likely to improve whereas patients with corpus-predominant gastritis are less likely to improve.<ref name="pmid16803603">{{cite journal |author=Vakil N, Talley NJ, Stolte M, Sundin M, Junghard O, Bolling-Sternevald E |title=Patterns of gastritis and the effect of eradicating Helicobacter pylori on gastro-oesophageal reflux disease in Western patients with non-ulcer dyspepsia |journal=Aliment. Pharmacol. Ther. |volume=24 |issue=1 |pages=55–63 |year=2006 |pmid=16803603 |doi=10.1111/j.1365-2036.2006.02964.x}}</ref> This may be due to antral erosions being due to hyperacidity the is corrected by treatment whereas corpus erosions are hypoacidic and treating this may increase the ability of the stomach to produce acid. <ref name="pmid16803603"/> Another study found that patients with gastritis or erosions were less likely to respond<ref name="pmid16416218">{{cite journal |author=Mazzoleni LE, Sander GB, Ott EA, ''et al'' |title=Clinical outcomes of eradication of Helicobacter pylori in nonulcer dyspepsia in a population with a high prevalence of infection: results of a 12-month randomized, double blind, placebo-controlled study |journal=Dig. Dis. Sci. |volume=51 |issue=1 |pages=89–98 |year=2006 |pmid=16416218 |doi=10.1007/s10620-006-3090-6}}</ref>, but this study did not separate patients with antral versus corpus erosions.
| | Does it have any plasmids? Are they important to the organism's lifestyle? |
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| Regarding how to treat:<ref name="pmid17608775"/>
| | ==Cell structure and metabolism== |
| * "Eradication rates achieved by first-line treatment with a proton pump inhibitor (PPI), clarithromycin, and amoxicillin have decreased to 70-85%, in part due to increasing clarithromycin resistance".
| | Describe any interesting features and/or cell structures; how it gains energy; what important molecules it produces. |
| * "Eradication rates may also be lower with 7 versus 14-day regimens."
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| Regarding follow-up of treatment<ref name="pmid17608775"/>, ''H. pylori'' antibiotic resistance is increasing<ref name="pmid15306603">{{cite journal |author=Mégraud F |title=H pylori antibiotic resistance: prevalence, importance, and advances in testing |journal=Gut |volume=53 |issue=9 |pages=1374–84 |year=2004 |pmid=15306603 |doi=10.1136/gut.2003.022111}}</ref> due to prior exposure of patients to macrolide antiobiotics and metronidazole.<ref name="pmid13679322">{{cite journal |author=McMahon BJ, Hennessy TW, Bensler JM, ''et al'' |title=The relationship among previous antimicrobial use, antimicrobial resistance, and treatment outcomes for Helicobacter pylori infections |journal=Ann. Intern. Med. |volume=139 |issue=6 |pages=463–9 |year=2003 |pmid=13679322 |doi=}}</ref>
| | ==Ecology== |
| | Describe any interactions with other organisms (included eukaryotes), contributions to the environment, effect on environment, etc. |
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| * "Testing to prove eradication should be performed in patients who receive treatment of ''H. pylori'' for peptic ulcer disease, individuals with persistent dyspeptic symptoms despite the test-and-treat strategy, those with ''H. pylori''-associated MALT lymphoma, and individuals who have undergone resection of early gastric cancer".
| | ==Pathology== |
| * "For patients with persistent ''H. pylori'' consider bismuth quadruple therapy. A PPI, levofloxacin, and amoxicillin for 10 days is more effective and better tolerated than bismuth quadruple therapy for persistent ''H. pylori''".
| | How does this organism cause disease? Human, animal, plant hosts? Virulence factors, as well as patient symptoms. |
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| A complication of treatment is selecting for "highly resistant enterococci that can persist for at least 3 years ".<ref name="pmid13679325">{{cite journal |author=Sjölund M, Wreiber K, Andersson DI, Blaser MJ, Engstrand L |title=Long-term persistence of resistant Enterococcus species after antibiotics to eradicate Helicobacter pylori |journal=Ann. Intern. Med. |volume=139 |issue=6 |pages=483–7 |year=2003 |pmid=13679325 |doi=}}</ref>
| | ==Application to Biotechnology== |
| | Does this organism produce any useful compounds or enzymes? What are they and how are they used? |
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| ==Prevention== | | ==Current Research== |
| It has been recommended to eradicate H. pylori world wide as was done for smallpox.<ref name="pmid9394771">{{cite journal |author=Graham DY |title=Can therapy even be denied for Helicobacter pylori infection? |journal=Gastroenterology |volume=113 |issue=6 Suppl |pages=S113–7 |year=1997 |pmid=9394771 |doi=}}</ref>
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| ==History==
| | Enter summaries of the most recent research here--at least three required |
| Barry Marshall and Robin Warren won the 2005 Nobel Prize in Physiology or Medicine for discovery of '''''Helicobacter pylori''''' in 1983.<ref name="pmid16339090">{{cite journal |author=Parsonnet J |title=Clinician-discoverers--Marshall, Warren, and H. pylori |journal=N. Engl. J. Med. |volume=353 |issue=23 |pages=2421–3 |year=2005 |pmid=16339090 |doi=10.1056/NEJMp058270}}</ref><ref name="pmid6145023">{{cite journal |author=Marshall BJ, Warren JR |title=Unidentified curved bacilli in the stomach of patients with gastritis and peptic ulceration |journal=Lancet |volume=1 |issue=8390 |pages=1311–5 |year=1984 |pmid=6145023 |doi=}}</ref>
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| ==References== | | ==References== |
| <references/>
| | [Sample reference] [http://ijs.sgmjournals.org/cgi/reprint/50/2/489 Takai, K., Sugai, A., Itoh, T., and Horikoshi, K. "''Palaeococcus ferrophilus'' gen. nov., sp. nov., a barophilic, hyperthermophilic archaeon from a deep-sea hydrothermal vent chimney". ''International Journal of Systematic and Evolutionary Microbiology''. 2000. Volume 50. p. 489-500.] |
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Classification
Higher order taxa
Domain; Phylum; Class; Order; family [Others may be used. Use Tree of Life link to find]
Species
Genus species
Description and significance
Describe the appearance, habitat, etc. of the organism, and why it is important enough to have its genome sequenced. Describe how and where it was isolated.
Include a picture or two (with sources) if you can find them.
Genome structure
Describe the size and content of the genome. How many chromosomes? Circular or linear? Other interesting features? What is known about its sequence?
Does it have any plasmids? Are they important to the organism's lifestyle?
Cell structure and metabolism
Describe any interesting features and/or cell structures; how it gains energy; what important molecules it produces.
Ecology
Describe any interactions with other organisms (included eukaryotes), contributions to the environment, effect on environment, etc.
Pathology
How does this organism cause disease? Human, animal, plant hosts? Virulence factors, as well as patient symptoms.
Application to Biotechnology
Does this organism produce any useful compounds or enzymes? What are they and how are they used?
Current Research
Enter summaries of the most recent research here--at least three required
References
[Sample reference] Takai, K., Sugai, A., Itoh, T., and Horikoshi, K. "Palaeococcus ferrophilus gen. nov., sp. nov., a barophilic, hyperthermophilic archaeon from a deep-sea hydrothermal vent chimney". International Journal of Systematic and Evolutionary Microbiology. 2000. Volume 50. p. 489-500.
