(Jones et al., 1931)
Veron & Chatelain, 1973
Campylobacter jejuni ( /
Campylobacter jejuni is in a genus of bacteria that is among the most common causes of bacterial infections in humans worldwide. Campylobacter means "curved rod", deriving from the Greek campylos (curved) and baktron (rod). "There is wide diversity in the genus. The species are metabolically and genetically different to the extent that one can question whether one genus is adequate to house all of the species."Of its many species, C. jejuni is considered one of the most important from both a microbiological and public health perspective.
C. jejuni is also commonly found in animal feces. Campylobacter is a helical-shaped, non-spore-forming, Gram-negative, microaerophilic, nonfermenting bacterium forming motile rods with a single polar flagellum, which are also oxidase-positive and grow optimally at 37 to 42 °C. When exposed to atmospheric oxygen, C. jejuni is able to change into a coccal form. This species of pathogenic bacteria is one of the most common causes of human gastroenteritis in the world. Food poisoning caused by Campylobacter species can be severely debilitating, but is rarely life-threatening. It has been linked with subsequent development of Guillain–Barré syndrome, which usually develops two to three weeks after the initial illness. Individuals with recent C. jejuni infections develop Guillain-Barré syndrome at a rate of 0.3 per 1000 infections, about 100 times more often than the general population.
Feces are the solid or semisolid remains of the food that could not be digested in the small intestine. Bacteria in the large intestine further break down the material. Feces contain a relatively small amount of metabolic waste products such as bacterially altered bilirubin, and the dead epithelial cells from the lining of the gut.
A helix, plural helixes or helices, is a type of smooth space curve, i.e. a curve in three-dimensional space. It has the property that the tangent line at any point makes a constant angle with a fixed line called the axis. Examples of helices are coil springs and the handrails of spiral staircases. A "filled-in" helix – for example, a "spiral" (helical) ramp – is called a helicoid. Helices are important in biology, as the DNA molecule is formed as two intertwined helices, and many proteins have helical substructures, known as alpha helices. The word helix comes from the Greek word ἕλιξ, "twisted, curved".
Pathogenic bacteria are bacteria that can cause disease. This article deals with human pathogenic bacteria. Although most bacteria are harmless or often beneficial, some are pathogenic, with the number of species estimated as fewer than a hundred that are seen to cause infectious diseases in humans. By contrast, several thousand species exist in the human digestive system.
In 1886 a pediatrician, Theodor Escherich, observed Campylobacters from diarrhea samples of children.The first isolation of C. jejuni was in Brussels, Belgium, from stool samples of a patient with diarrhea.
Theodor Escherich was a German-Austrian pediatrician and a professor at universities in Graz and Vienna. He discovered the bacterium Escherichia coli, which was named after him in 1919, and determined its properties.
Campylobacter is a genus of Gram-negative bacteria. Campylobacter typically appear comma- or s-shaped, and are motile.
Campylobacteriosis is an infectious disease caused by bacteria of the genus Campylobacter. In most people who become ill with campylobacteriosis, symptoms develop within two to five days of exposure to the organism and illness typically lasts seven days following onset.Infection with C. jejuni usually results in enteritis, which is characterised by abdominal pain, diarrhea, fever, and malaise. Diarrhea itself can vary in severity from loose to bloody stools. The disease is usually self-limiting. However, it does respond to antibiotics. Severe (accompanying fevers, blood in stools) or prolonged cases may require erythromycin, azithromycin, ciprofloxacin, or norfloxacin. Fluid replacement via Oral Rehydration Salts may be needed and intravenous fluid may be required for serious cases. Possible complications of campylobacteriosis include Guillain–Barré syndrome and reactive arthritis.
Enteritis is inflammation of the small intestine. It is most commonly caused by food or drink contaminated with pathogenic microbes, such as serratia, but may have other causes such as NSAIDs, cocaine, radiation therapy as well as autoimmune conditions like Crohn's disease and coeliac disease. Symptoms include abdominal pain, cramping, diarrhoea, dehydration, and fever.
Malaise is a feeling of general discomfort, uneasiness, or pain, often the first sign of an infection or other disease. The word has existed in the French language since at least the 12th century.
Erythromycin is an antibiotic used for the treatment of a number of bacterial infections. This includes respiratory tract infections, skin infections, chlamydia infections, pelvic inflammatory disease, and syphilis. It may also be used during pregnancy to prevent Group B streptococcal infection in the newborn, as well as to improve delayed stomach emptying. It can be given intravenously and by mouth. An eye ointment is routinely recommended after delivery to prevent eye infections in the newborn.
Studies on the pathogenesis of C. jejuni show that for this organism to cause disease, the susceptibility of the host and the relative virulence of the infecting strain are both important. Infection results from the ingestion of contaminated food or water, and the infective dose can be as low as 800 organisms. To initiate infection, the organism must penetrate the gastrointestinal mucus, which it does using its high motility and spiral shape. The bacteria must then adhere to the gut enterocytes and can then induce diarrhea by toxin release. C. jejuni releases several different toxins, mainly enterotoxin and cytotoxins, which vary from strain to strain and correlate with the severity of the enteritis. During infection, levels of all immunoglobulin classes rise. Of these, IgA is the most important because it can cross the gut wall. IgA immobilises organisms, causing them to aggregate and activate complement, and also gives short-term immunity against the infecting strain of organism.The bacteria colonize the small and large intestines, causing inflammatory diarrhea with fever. Stools contain leukocytes and blood. The role of toxins in pathogenesis is unclear. C jejuni antigens that cross-react with one or more neural structures may be responsible for triggering the Guillain–Barré syndrome.
Mucus is a polymer. It is a slippery aqueous secretion produced by, and covering, mucous membranes. It is typically produced from cells found in mucous glands, although it may also originate from mixed glands, which contain both serous and mucous cells. It is a viscous colloid containing inorganic salts, antiseptic enzymes, immunoglobulins, and glycoproteins such as lactoferrin and mucins, which are produced by goblet cells in the mucous membranes and submucosal glands. Mucus serves to protect epithelial cells in the respiratory, gastrointestinal, urogenital, visual, and auditory systems; the epidermis in amphibians; and the gills in fish, against infectious agents such as fungi, bacteria and viruses. Most of the mucus produced is in the gastrointestinal tract.
Guillain–Barré syndrome (GBS) is a rapid-onset muscle weakness caused by the immune system damaging the peripheral nervous system. The initial symptoms are typically changes in sensation or pain along with muscle weakness, beginning in the feet and hands. This often spreads to the arms and upper body, with both sides being involved. The symptoms develop over hours to a few weeks. During the acute phase, the disorder can be life-threatening, with about 15% developing weakness of the breathing muscles requiring mechanical ventilation. Some are affected by changes in the function of the autonomic nervous system, which can lead to dangerous abnormalities in heart rate and blood pressure.
Hypoacylated lipopolysaccharide (LPS) from C. jejuni induces moderate TLR4-mediated inflammatory response in macrophages and such LPS bioactivity may eventually result in the failure of local and systemic bacterial clearance in patients. At the same time, moderation of anti-bacterial responses may be advantageous for infected patients in clinical practice, since such an attenuated LPS may not be able to induce severe sepsis in susceptible individuals.
C. jejuni is commonly associated with poultry, and it naturally colonises the digestive tract of many bird species. All types of poultry and wild birds can become colonized with Campylobacter. One study found that 30% of European starlings in farm settings in Oxfordshire, United Kingdom, were carriers of C. jejuni. It is also common in cattle, and although it is normally a harmless commensal of the gastrointestinal tract in these animals, it can cause campylobacteriosis in calves. It has also been isolated from wombat and kangaroo feces, being a cause of bushwalkers' diarrhea. Contaminated drinking water and unpasteurized milk provide an efficient means for distribution. Contaminated food is a major source of isolated infections, with incorrectly prepared meat and poultry as the primary source of the bacteria.Moreover, surveys show that 20 to 100% of retail chickens are contaminated. This is not overly surprising, since many healthy chickens carry these bacteria in their intestinal tracts. Raw milk is also a source of infections. The bacteria are often carried by healthy cattle and by flies on farms. Unchlorinated water may also be a source of infections. However, properly cooking chicken, pasteurizing milk, and chlorinating drinking water kill the bacteria. Campylobacter is not, in contrast to Salmonella, transmitted vertically and therefore humans do not get infected by consuming eggs.
Local complications of Campylobacter infections occur as a result of direct spread from the gastrointestinal tract and can include cholecystitis, pancreatitis, peritonitis, and massive gastrointestinal hemorrhage. Extraintestinal manifestations of Campylobacter infection are quite rare and may include meningitis, endocarditis, septic arthritis, osteomyelitis, and neonatal sepsis. Bacteremia is detected in <1% of patients with Campylobacter enteritis and is most likely to occur in patients who are immunocompromised or among the very young or very old.Transient bacteremia in immunocompetent hosts with C. jejuni enteritis may be more common, but not detected because most strains are rapidly cleared by the killing action of normal human serum and because blood cultures are not routinely performed for patients with acute gastrointestinal illness.
Serious systemic illness caused by Campylobacter infection rarely occurs, but can lead to sepsis and death. The case-fatality rate for Campylobacter infection is 0.05 per 1000 infections. For instance, one major possible complication that C. jejuni can cause is Guillain–Barré syndrome, which induces neuromuscular paralysis in a sizeable percentage of those who suffer from it. Over time, the paralysis is typically reversible to some extent; nonetheless, about 20% of patients with GBS are left disabled, and around 5% die. Another chronic condition that may be associated with Campylobacter infection is what was formerly known as Reiter's syndrome, a form of reactive arthritis.Reactive arthritis is a complication strongly associated with a particular genetic make-up. That is, persons who have the human lymphocyte antigen B27 (HLA-B27) are most susceptible. Most often, the symptoms of reactive arthritis will occur up to several weeks after infection.
An estimated 2 million cases of Campylobacter enteritis occur annually, accounting for 5–7% of cases of gastroenteritis.Campylobacter organisms have a large animal reservoir, with up to 100% of poultry, including chickens, turkeys, and waterfowl, having asymptomatic intestinal infections. The major reservoirs of C. fetus are cattle and sheep. Nonetheless, the incidence of Campylobacter infections has been declining. Changes in the incidence of culture-confirmed Campylobacter infections have been monitored by the Foodborne Diseases Active Surveillance Network (FoodNet) since 1996. In 2010, Campylobacter incidence showed a 27% decrease compared with 1996–1998. In 2010, the incidence was 13.6 cases per 100,000 population, and this did not change significantly compared with 2006–2008.
C. jejuni infections are extremely common worldwide, although exact figures are not available. New Zealand reported the highest national campylobacteriosis rate, which peaked in May 2006 at 400 per 100,000 population.
Campylobacter organisms are isolated more frequently from males than females. Homosexual men appear to be at increased risk for infection with atypical Campylobacter species such as Helicobacter cinaedi and Helicobacter fennelliae.
Campylobacter infections can occur in all age groups. Studies show a peak incidence in children younger than 1 year and in persons aged 15–29 years. The age-specific attack rate is highest in young children. In the United States, the highest incidence of Campylobacter infection in 2010 was in children younger than 5 years and was 24.4 cases per 100,000 population,However, the rate of fecal cultures positive for Campylobacter species is greatest in adults and older children.
Patients with Campylobacter infection should drink plenty of fluids as long as the diarrhea lasts to maintain hydration. One must drink plenty of fluids and get rest. If he or she cannot drink enough fluids to prevent dehydration or if the symptoms are severe, medical help is indicated. In more severe cases, certain antibiotics can be used and can shorten the duration of symptoms if given early in the illness.Moreover, maintenance of electrolyte balance, not antibiotic treatment, is the cornerstone of treatment for Campylobacter enteritis. Indeed, most patients with this infection have a self-limited illness and do not require antibiotics at all. Nevertheless, antibiotics should be used in specific clinical circumstances. These include high fevers, bloody stools, prolonged illness (symptoms that last >1 week), pregnancy, infection with HIV, and other immunocompromised states.
Some simple food-handling practices can help prevent Campylobacter infections.
The genome of C. jejuni strain NCTC11168 was published in 2000, revealing 1,641,481 base pairs (30.6% G+C) predicted to encode 1,654 proteins and 54 stable RNA species. The genome is unusual in that virtually no insertion sequences or phage-associated sequences and very few repeat sequences are found. One of the most striking findings in the genome was the presence of hypervariable sequences. These short homopolymeric runs of nucleotides were commonly found in genes encoding the biosynthesis or modification of surface structures, or in closely linked genes of unknown function. The apparently high rate of variation of these homopolymeric tracts may be important in the survival strategy of C. jejuni.
Initial transposon mutagenesis screens revealed 195 essential genes, although this number is likely to go up with additional analysis.
C. jejuni is naturally competent for genetic transformation.Natural genetic transformation is a sexual process involving DNA transfer from one bacterium to another through the intervening medium, and the integration of the donor sequence into the recipient genome by homologous recombination. C. jejuni freely takes up foreign DNA harboring genetic information responsible for antibiotic resistance. Antibiotic resistance genes are more frequently transferred in biofilms than between planktonic cells (single cells that float in liquid media).
|Growth at 25 °C||−|
|Growth at 35–37 °C||+|
|Growth at 42 °C||+|
|Growth on MacConkey agar||+|
|Motility (wet mount)||+|
|Resistance to nalidixic acid||−|
|Resistance to cephalothin||+|
Under light microscopy, C. jejuni has a characteristic "sea-gull" shape as a consequence of its helical form. Campylobacter is grown on specially selective "CAMP" agar plates at 42 °C, the normal avian body temperature, rather than at 37 °C, the temperature at which most other pathogenic bacteria are grown. Since the colonies are oxidase positive, they usually only grow in scanty amounts on the plates. Microaerophilic conditions are required for luxurious growth. A selective blood agar medium (Skirrow's medium) can be used. Greater selectivity can be gained with an infusion of a cocktail of antibiotics: vancomycin, polymixin-B, trimethoprim, and actidione ([Preston's agar]), and growth under microaerophilic conditions at 42 °C.
Lemierre's syndrome refers to infectious thrombophlebitis of the internal jugular vein. It most often develops as a complication of a bacterial sore throat infection in young, otherwise healthy adults. The thrombophlebitis is a serious condition and may lead to further systemic complications such as bacteria in the blood or septic emboli.
Clostridium perfringens is a Gram-positive, rod-shaped, anaerobic, spore-forming pathogenic bacterium of the genus Clostridium. C. perfringens is ever-present in nature and can be found as a normal component of decaying vegetation, marine sediment, the intestinal tract of humans and other vertebrates, insects, and soil. It has the shortest reported generation time of any organism at 6.3 minutes in thioglycolate medium.
Septic arthritis, also known as joint infection or infectious arthritis, is the invasion of a joint by an infectious agent resulting in joint inflammation. Symptoms typically include redness, heat, and pain in a single joint associated with a decreased ability to move the joint. Onset is usually rapid. Other symptoms may include fever, weakness, and headache. Occasionally, more than one joint may be involved.
Gastroenteritis, also known as infectious diarrhea, is inflammation of the gastrointestinal tract—the stomach and small intestine. Symptoms may include diarrhea, vomiting and abdominal pain. Fever, lack of energy and dehydration may also occur. This typically lasts less than two weeks. It is not related to influenza, though it has been called the "stomach flu".
Campylobacteriosis is an infection by the Campylobacter bacterium, most commonly C. jejuni. It is among the most common bacterial infections of humans, often a foodborne illness. It produces an inflammatory, sometimes bloody, diarrhea or dysentery syndrome, mostly including cramps, fever and pain.
Salmonellosis is a symptomatic infection caused by bacteria of the Salmonella type. The most common symptoms are diarrhea, fever, abdominal cramps, and vomiting. Symptoms typically occur between 12 hours and 36 hours after exposure, and last from two to seven days. Occasionally more significant disease can result in dehydration. The old, young, and others with a weakened immune system are more likely to develop severe disease. Specific types of Salmonella can result in typhoid fever or paratyphoid fever.
Staphylococcal enteritis is an inflammation that is usually caused by eating or drinking substances contaminated with staph enterotoxin. The toxin, not the bacterium, settles in the small intestine and causes inflammation and swelling. This in turn can cause abdominal pain, cramping, dehydration, diarrhea and fever.
Mycoplasma pneumonia is a form of bacterial pneumonia caused by the bacterial species Mycoplasma pneumoniae.
Bacillary dysentery is a type of dysentery, and is a severe form of shigellosis.
Reactive arthritis, formerly known as Reiter's syndrome, is a form of inflammatory arthritis that develops in response to an infection in another part of the body (cross-reactivity). Coming into contact with bacteria and developing an infection can trigger the disease. By the time the patient presents with symptoms, often the "trigger" infection has been cured or is in remission in chronic cases, thus making determination of the initial cause difficult.
Clostridial necrotizing enteritis (CNE), also called enteritis necroticans or pigbel, is a potentially fatal type of food poisoning caused by a β-toxin of Clostridium perfringens, Type C. It occurs in some developing countries, but was also documented in Germany following World War II, where it was called "Darmbrand". The toxin is normally inactivated by certain proteolytic enzymes and by normal cooking, but when these protections are impeded, and low protein is consumed, the disease emerges.
Acute motor axonal neuropathy (AMAN) is a variant of Guillain–Barré syndrome. It is characterized by acute paralysis and loss of reflexes without sensory loss. Pathologically, there is motor axonal degeneration with antibody-mediated attacks of motor nerves and nodes of Ranvier.
Antiganglioside antibodies that react to self-gangliosides are found in autoimmune neuropathies. These antibodies were first found to react with cerebellar cells. These antibodies show highest association with certain forms of Guillain–Barré syndrome.
Arcobacter is a genus of Gram-negative, spiral-shaped bacteria in the class Epsilonproteobacteria. It shows an unusually wide range of habitats, and some species can be human and animal pathogens. Species of the genus Arcobacter are found in both animal and environmental sources, making it unique among the epsilonproteobacteria. This genus currently consists of five species: A. butzleri, A. cryaerophilus, A. skirrowii, A. nitrofigilis, and A. sulfidicus, although several other potential novel species have recently been described from varying environments. Three of these five known species are pathogenic. Members of this genus were first isolated in 1977 from aborted bovine fetuses. They are aerotolerant, Campylobacter-like organisms, previously classified as Campylobacter. The genus Arcobacter, in fact, was created as recently as 1992. Although they are similar to this other genus, Arcobacter species can grow at lower temperatures than Campylobacter, as well as in the air, which Campylobacter cannot.
Gastrointestinal campylobacteriosis is caused by Campylobacter jejuni or Campylobacter coli. Although it is a commensal in the gastrointestinal tract of many species, it can cause diarrhea - mainly in young animals. It is most commonly seen in cattle, but may also infect many other species, including humans. Campylobacter is spread horizontally via the fecal-oral route.
Campylobacter coli is a Gram-negative, microaerophilic, non-endospore-forming, S-shaped bacterial species within genus Campylobacter.
Clostridioides difficile, also known as C. difficile, C. diff, or sometimes CDF/cdf, is a species of Gram-positive spore-forming bacterium.