''Helicobacter felis'' is a

bacterial Bacteria (; : bacterium) are ubiquitous, mostly free-living organisms often consisting of one biological cell. They constitute a large domain of prokaryotic microorganisms. Typically a few micrometres in length, bacteria were among the ...

species A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of Taxonomy (biology), ...

in the

Helicobacteraceae The Campylobacterales are an order of Campylobacterota which make up the epsilon subdivision, together with the small family Nautiliaceae. They are Gram-negative. Most of the species are microaerophilic.Garrity, George M.; Brenner, Don J.; Krieg ...

family,

Campylobacterales The Campylobacterales are an order of Campylobacterota which make up the epsilon subdivision, together with the small family Nautiliaceae. They are Gram-negative. Most of the species are microaerophilic.Garrity, George M.; Brenner, Don J.; Kri ...

order,

Helicobacter ''Helicobacter'' is a genus of gram-negative bacteria possessing a characteristic helical shape. They were initially considered to be members of the genus '' Campylobacter'', but in 1989, Goodwin ''et al.'' published sufficient reasons to justi ...

genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...

. This bacterium is

Gram-negative Gram-negative bacteria are bacteria that, unlike gram-positive bacteria, do not retain the crystal violet stain used in the Gram staining method of bacterial differentiation. Their defining characteristic is that their cell envelope consists ...

microaerophilic A microaerophile is a microorganism that requires environments containing lower levels of dioxygen than that are present in the atmosphere (i.e. < 21% O₂; typically 2–10% O₂) for optimal growth. A more r ...

urease Ureases (), functionally, belong to the superfamily of amidohydrolases and phosphotriesterases. Ureases are found in numerous Bacteria, Archaea, fungi, algae, plants, and some invertebrates. Ureases are nickel-containing metalloenzymes of high ...

-positive, and spiral-shaped. Its type strain is CS1T (= ATCC 49179T). It can be

pathogenic In biology, a pathogen (, "suffering", "passion" and , "producer of"), in the oldest and broadest sense, is any organism or agent that can produce disease. A pathogen may also be referred to as an infectious agent, or simply a germ. The term ...

. ''

Helicobacter pylori ''Helicobacter pylori'', previously known as ''Campylobacter pylori'', is a gram-negative, Flagellum#bacterial, flagellated, Bacterial cellular morphologies#Helical, helical bacterium. Mutants can have a rod or curved rod shape that exhibits l ...

'' (''H. pylori'') is by far the best known ''Helicobacter'' species, primarily because humans infected with it may develop

gastrointestinal tract The gastrointestinal tract (GI tract, digestive tract, alimentary canal) is the tract or passageway of the Digestion, digestive system that leads from the mouth to the anus. The tract is the largest of the body's systems, after the cardiovascula ...

diseases such as stomach inflammation,

stomach ulcers Peptic ulcer disease is when the inner part of the stomach's gastric mucosa (lining of the stomach), the first part of the small intestine, or sometimes the lower esophagus, gets damaged. An ulcer in the stomach is called a gastric ulcer, while ...

duodenal ulcers Peptic ulcer disease is when the inner part of the stomach's gastric mucosa (lining of the stomach), the first part of the small intestine, or sometimes the lower esophagus The esophagus (American English), oesophagus (British English), ...

stomach cancer Stomach cancer, also known as gastric cancer, is a malignant tumor of the stomach. It is a cancer that develops in the Gastric mucosa, lining of the stomach. Most cases of stomach cancers are gastric carcinomas, which can be divided into a numb ...

s of the nonlymphoma type, and various subtypes of extranodal marginal zone lymphomass, e.g. those of the

stomach The stomach is a muscular, hollow organ in the upper gastrointestinal tract of Human, humans and many other animals, including several invertebrates. The Ancient Greek name for the stomach is ''gaster'' which is used as ''gastric'' in medical t ...

small intestines The small intestine or small bowel is an organ in the gastrointestinal tract where most of the absorption of nutrients from food takes place. It lies between the stomach and large intestine, and receives bile and pancreatic juice through the ...

large intestines The large intestine, also known as the large bowel, is the last part of the gastrointestinal tract and of the digestive system in tetrapods. Water is absorbed here and the remaining waste material is stored in the rectum as feces before being rem ...

, and rectumn. ''H. pylori'' is also associated with the development of

bile duct cancer Cholangiocarcinoma, also known as bile duct cancer, is a type of cancer that forms in the bile ducts. Symptoms of cholangiocarcinoma may include abdominal pain, yellowish skin, weight loss, generalized itching, and fever. Light colored stoo ...

and has been associated with a wide range of other diseases although its role in the development of many of these other diseases requires further study. Humans infected with ''H. felis'' may also develop some of the same gastrointestinal diseases viz., stomach inflammation, stomach ulcers, duodenal ulcers, stomach cancers that are not lymphomas, and extranodal marginal B cell lymphomas of the stomach. Other non-''H. pylori'' species that are known to be associated with these gastrointestinal diseases are '' Helicobacter bizzozeronii, Helicobacter salomonis, Helicobacter suis,'' and '' Helicobacter heilmannii s.s''. Because of their disease associations, these four ''Helicobacter'' species plus ''H. felis'' are often group together and termed '' Helicobacter heilmannii sensu lato''. ''H. felis'' bacteria are detected in the stomachs of their natural hosts - cats, dogs, rabbits, and cheetahs. Reports suggest that individuals, including children, are infected with this bacterium by having close contact with one of these infected animals: ''H. heilmanni s.l.''-associated diseases, including those associated with ''H. felis'', appear to be

zoonotic diseases A zoonosis (; plural zoonoses) or zoonotic disease is an infectious disease of humans caused by a pathogen (an infectious agent, such as a virus A virus is a submicroscopic infectious agent that replicates only inside the living Cell (b ...

, i.e.

infectious diseases infection is the invasion of tissues by pathogens, their multiplication, and the reaction of host tissues to the infectious agent and the toxins they produce. An infectious disease, also known as a transmissible disease or communicable dise ...

that are caused by

pathogen In biology, a pathogen (, "suffering", "passion" and , "producer of"), in the oldest and broadest sense, is any organism or agent that can produce disease. A pathogen may also be referred to as an infectious agent, or simply a Germ theory of d ...

that spread from animals to humans. It is important to diagnose ''H. felis'' and other ''H. heilmannii sensu lato'' infections in patients with the cited upper gastrointestinal tract diseases, including in particular extranodal marginal zone lymphoma of the stomach, because some of them have been successfully treated and cured using antibiotic-based drug regimens (e.g.

amoxicillin Amoxicillin is an antibiotic medication belonging to the aminopenicillin class of the penicillin family. The drug is used to treat bacterial infections such as middle ear infection, strep throat, pneumonia, skin infections, odontogenic inf ...

clarithromycin Clarithromycin, sold under the brand name Biaxin among others, is an antibiotic used to treat various bacterial infections. This includes strep throat, pneumonia, skin infections, '' H. pylori'' infection, and Lyme disease, among others. Clari ...

, plus a

proton pump inhibitor Proton-pump inhibitors (PPIs) are a class of medications that cause a profound and prolonged reduction of stomach acid production. They do so by irreversibly inhibiting the stomach's H+/K+ ATPase proton pump. The body eventually synthesizes ne ...

metronidazole Metronidazole, sold under the brand name Flagyl and Metrogyl among others, is an antibiotic and antiprotozoal medication. It is used either alone or with other antibiotics to treat pelvic inflammatory disease, endocarditis, and bacterial vagino ...

, clarithromycin, plus a proton pump inhibitor) directed against the instigating bacterium.

References

External links

*
Type strain of ''Helicobacter felis'' at Bac''Dive'' - the Bacterial Diversity Metadatabase
Campylobacterota Bacteria described in 1991 {{Campylobacterota-stub

References

Further reading

External links