1. Campylobacter Spirally small, curved, G-ve, Motile, NS, NC bacteria.
They are comma, S, or “gull-wing” shaped spiral rods.
Motile by single polar unsheathed flagellum at one or both ends.
Have long been known to cause Diarrhea in animals but their role in human diarrhea was only established in 1970.
Reason:
Gram staining shows pleomorphic G-ve bacilli with short curved and spiral forms of bacteria.Typical S shaped.
Chakraborty 359

2. Coloured scanning electron micrograph (SEM) of a Campylobacter jejuni bacterium. This motile, Gram-negative bacterium possesses long flagella, at either end, which enable it to move

3. Campylobacter is the second most common cause of bacterial foodborne illness in the United States after Salmonella

4. 16 Species Medically important are
C.jejuni, C.coli, C.upsaliensis: Causing human diarrhea.
C.fetus : Cause extraintestinal infection.
C.sputorum, C.rectus: Periodontal disease.
Small intestine The upper part consist of the duodenum(connected to the stomach), the jejunum, and the ileum(connected to the large intestine). 6 mter long.
C.Jejuni most common enteric pathogen responsible for 90-95% Campylobacter infection.
Habitat of campylobacter………………………..in their faeces(Chakraborty, 360).

5. Culture Characteristics
Campylobacter are microaerophilic
thermophilic* (growing well at 420C)
Capnophilic(require 10% CO2 )
Survive in Cary Blair media.
Selective Media:
1. Modified Skirrow Media contining blood agar base, & antibiotics (Vancomycin, Trimethoprim, and Polymyxin B).
2. Campy-Brucella agar with antibiotics
Rectal swab or stool swab or 1 or 2 drop of liquid stool specimen are inoculated directly on the surface of the agar medium.
Incubation: 420 C for 48 to 72 hours.

6. Culture characteristics
Colonies are flat grey, irregular shaped and moist/ glistening entire edges.

7. Biochemical reactions
360 pg P Chakroborty.
Must tell Hippurate hydrolysis test

8. Epidemiology
Campylobacter infection: Zoonotic with variety of animal serving as reservoir Chickens, domestic animals (Cattle and Swine) and birds. Source of infection is food of animal origin, especially raw milk.
It is part of the normal intestinal flora of domestic animals and birds and is shed in their feces.
Contaminated poultry are responsible for more than half of the Campylobacter infection.
Human acquire infection with C.jejuni and C.coli after consumption of contaminated food, milk or water.
Once a person is infected, the organism can be transmitted from person to person by faecal-oral route.
Incidence rate high among children less than 2 year old and young adults(20 to 40 years old).
Poultry(Chickens and turkey). Dog & Cat are reported to be the source of campylobacters.
Frequent exposure to C.jejuni probably leads to development of immunity with advancement of age.

9. Pathogenesis & Immunity
Infectious dose and host immunity determine whether gastroenteric disease develops
Some people infected with as few as 500 organisms while others need >106 CFU
Pathogenesis not fully characterized
No good animal model
Damage (ulcerated, edematous and bloody) to the mucosal surfaces of the jejunum, ileum, colon
Inflammatory process consistent with invasion of the organisms into the intestinal tissue; M-cell (Peyer’s patches) uptake and presentation of antigen to underlying lymphatic system
Non-motile & adhesin-lacking strains are avirulent

10. Pathogenicity
Occurs with in 2-4 days(range of incubation period, 1-7 days) of ingestion of contaminated food, milk or water.
Cause acute gastroenteritis, last for days to several weeks, usually self limiting.
Infection first jejunum and ileum and later spread distally to affect terminal ileum, colon and rectum
C.jejuni is invasive, multiply in small intestine, penetrate gut epithelium and disrupt fluid absorption.
Virulence factor: Produce enterotoxin
cytotoxin
Adhesions
Intracellular survival
Ability to penetrate cells
Must tell Traveller Diarrhoea and pseudoappendicitis(without inflammation of the appendix).

11. Clinical feature
Fever, headache, myalgia and intestinal– abdominal cramping and watery diarrhoea with or without blood.
Cause both traveller’s diarrhoea and pseudo appendicitis.
Complication include Guillain Barre syndrome(GBS), septic abortion and reactive arthritis.
GBS associated with specific C.jejuni serotype O:19.
Clinical symptom both systemic--- fever, headache, myalgia and intestinal– abdominal cramping and diarrhoea which may or may not contain blood or may not be bloody.
Guillain Barre Syndrome: See notes

12. GBS(Guillain-Barre Syndrome)
C.jejuni most recognized antecedent cause of GBS, an acute paralytic disease of the peripheral nervous system.
20-40% of GBS patients are infected with C.jejuni which may appear 1-2 weeks after the onset of acute campylobacter illness.
It is believed that antigenic cross reactivity between surface lipopolysaccharides of some strains of campylobacter and peripheral nerve gangliosides. Thus antibodies directed against specific strains of Campylobacter can damage neural tissue in peripheral nervous system.
What is Guillain-Barré syndrome (GBS)?
Guillain-Barré syndrome (say "ghee-YAN bah-RAY") is a problem with your nervous system. It causes muscle weakness, loss of reflexes, and numbness or tingling in your arms, legs, face, and other parts of your body.
Guillain-Barré syndrome (GBS) can cause paralysis and lead to death. But most people get better and have few lasting problems.
GBS is rare.
What causes Guillain-Barré syndrome?
Experts don't know what causes GBS. They think that the nerves are attacked by your body’s own defense system (the immune system). This is called an autoimmune disease.
In GBS, the immune system attacks the covering (myelin sheath ) of certain nerves. This causes nerve damage.
Infections that may trigger GBS
GBS usually begins to affect the nerves after you've had a viral or bacterial infection. Often it is after an infection of the lungs or stomach and intestines.
Infections that may trigger GBS include:
Campylobacter jejuni, which can cause a type of food poisoning.
Mycoplasma, which can cause pneumonia.
Cytomegalovirus (CMV), which can cause fever, chills, sore throat, swollen glands, body aches, and fatigue.
Epstein-Barr virus (EBV), which can cause mononucleosis (mono).
Varicella-zoster virus, which can cause chickenpox and shingles.
What are the symptoms?
Symptoms of GBS include:
Numbness or tingling in your hands and feet and sometimes around the mouth and lips.
Muscle weakness in your legs and arms and the sides of your face.
Trouble speaking, chewing, and swallowing.
Not being able to move your eyes.
Back pain.
Symptoms usually start with numbness or tingling in the fingers and toes. Over several days, muscle weakness in the legs and arms develops. After about 4 weeks, most people begin to get better.
You may need to be treated in the hospital for the first few weeks. This is because GBS can be deadly if weakness spreads to muscles that control breathing, heart rate, and blood pressure.
Call your doctor or get help right away if you think you might have GBS.
How is Guillain-Barré syndrome diagnosed?
Your doctor will ask when your symptoms started and how they have changed. He or she also may ask if you've had any recent infections.
Two signs are important in helping your doctor decide if you have GBS:
Your arms and legs are getting weaker.
You are losing your reflexes, which are automatic body movements that you can't control.
Your doctor also may do tests, such as a lumbar puncture and a nerve conduction study.
If the diagnosis isn't clear, you may be referred to a doctor who specializes in the nervous system (neurologist).
How is it treated?
GBS usually is treated in the hospital. The hospital staff will watch you carefully to be sure you don't get worse or get an infection. Your breathing, heart rate, and blood pressure are carefully tracked. Some people need a ventilator to help them breathe.

13. Laboratory Identification
Specimen Collection and Processing:
Feces refrigerated & examined within few hours
Rectal swabs in semisolid transport medium
Blood drawn for C. fetus
Microscopy:
Gull-wing appearance in Gram stain
Darting motility in fresh stool
Fecal leukocytes are commonly present
Culture
Feces/ rectal swab plated on selective media(Butzler’s selective medium, Skirrow Campylobacter selective medium, Campy BAP.
Growth at 37o, or 42-43oC.
Colonies typically flat, effuse & tendency to spread on moist agar. Nonhaemolytic, grey or colorless, moist and flat.
From Surinder Singh pg.401.
The gull wing is an aircraft's wing configuration with a prominent bend in the wing somewhere along the span, generally near the wing root. Its name is derived from the seabirds which it resembles. It has been incorporated in aircraft for many reason.
Campylobacter Agar with 5 Antimicrobics and 10% Sheep Blood (Campy-BAP) is a selective medium for the primary isolation of
Campylobacter jejuni from stool specimens.
Campylobacter Agar with 5 Antimicrobics and 10% Sheep Blood (Campy-BAP) is a selective medium for the primary isolation of Campylobacter jejuni from stool specimens. This medium supports the growth of Campylobacter species due to its content of peptones, dextrose, yeast extract and blood.     The peptones supply nitrogenous compounds, carbon, sulfur and trace ingredients. Yeast extract is a source of the B vitamins. Dextrose is utilized as an energy source. Sheep blood supplies additional nutrients.     The incorporation of the antimicrobial agents, amphotericin B, cephalothin, polymyxin B, trimethoprim and vancomycin, suppresses the growth of the normal microbial flora in fecal specimens, thereby facilitating isolation of C. jejuni.

14. Hippurate hydrolysis (C. jejuni is positive).
Identification:
Growth at 25o, 37o, or 42-43oC
Hippurate hydrolysis (C. jejuni is positive).
1% Sodium Hippurate+ Suspected isolate colonies
Indicator Ninhydrin is added to detect glycine by turning inoculated broth deep purple colour.
370C
Benzoic acid +Glycine
2hours

15. Serology & Molecular test
CFT & ELISA: Detect recent infection with C.jejuni or C.coli.
PCR amplification of the 16S rRNA gene and sequencing .
Treatment
Gastroenteritis, Infection is self-limited and is managed by fluid and electrolyte replacement.
Severe gastroenteritis treated with erythromycin and Ciprofloxacin.
Prevention
Potentially contaminated food, such as poultry, should be throughly cooked, and milk and milk prodcuts should be pasteurised.
Surinder Singh

16. Helicobacter
First observed in 1983 as Campylobacter-like organisms (formerly Campylobacter pyloridis) in the human stomachs of patients peptic ulcer disease(PUD) and gastric cancer.
Helicobacter pylori is the prototype organism in this group. It is associated with antral gastritis, duodenal ulcer disease, peptic (gastric )ulcers, and gastric carcinoma.
Features that distinguish this organism from campylobacter are its multiple sheathed flagella, its strong hydrolysis of urea and unique fatty acid profile.
Observe the a unipolar tuft of lophotrichous flagella in picture

17. H.pylori
Gram negative spirally curved bacilli, NS. Spheroid or coccoid in old culture.
Very Motile  corkscrew motion with a unipolar tuft of lophotrichous flagella(Other Helicobacter posses multiple bipolar sheathed flagella).
Culture: Microaerophilic, 5-10% CO2 & high humidity. Growth at 370C, not 250C or 420C. Can grow in Skirrow Campylobacter selective medium.
Produces circular, convex and translucent colonies after 3-7 days.
Biochemical : Urease production(Rapid diagnostic).
Catalase, Oxidase production
Does not metabolize carbohydrates or reduce nitrates.

18. Colonises the gastric mucosa of almost 50% of the adult population.
Adapted to human gastric mucosa.
Though contraversial but claims, human acquired infection as zoonoses from the stomach of other mammals (cat, dog, mice rats etc) each with its own helicobacter species.
Person to person transmission by oral-oral and faecal-oral routes.
Important Human Pathogens:
Helicobacter pylori , H. cinaedi , H. fenneliae
H. cinaedi , H. fenneliae are enteic Helicobacter and have been implicated as causative agents of gastroenteritis in immunocompromised individuals.
H.Cinaedi and H.fenneliae are assoicated with proctitis in HIV patient.

19. Virulence factors
H.pylori produce cytotoxin which cause vacuolation of gastric mucosa.
Cag , pathogenicity gene island, a group of genes consist of cag encoding for cag A protein, and vac(vacuolating cytotoxin gene) along with over 40 genes.
Cag A is injected by H.pylori into human gastric epithelial cell and affect the host cell protein expression inducing cytokine release, cytoskeletal changes and proliferation to enable H.pylori to successfully colonise gastric epithelium.
Urease released by H.pylori producing ammonia ions that neutralise stomach acid in the vicinity of the organism, thus favoring bacterial multiplication.
Bacterial antigen cross react with antran gastric antigen stimulating an autoimmune response.
Protease produced by the organism degrade gastric mucosa.
Ammonia may also cause injury and potentiate the effect of a cytotoxin.
The inner surface of the stomach is lined by a mucous membrane known as the gastric mucosa. The mucosa is always covered by a layer of thick mucus that is secreted by tall columnar epithelial cells. Gastric mucus is a glycoprotein that serves two purposes: the lubrication of food masses in order to facilitate movement within the stomach and the formation of a protective layer over the lining epithelium of the stomach cavity. This protective layer is a defense mechanism the stomach has against being digested by its own protein-lyzing enzymes, and it is facilitated by the secretion of bicarbonate into the surface layer from the underlying mucosa. The acidity, or hydrogen ion concentration, of the mucous layer measures pH7 (neutral) at the area immediately adjacent to the epithelium and becomes more acidic (pH2) at the luminal level. 

20. Pathogenesis
H.Pylori colonizes surface of gastric mucosa, especially antrum(Any part may be colonized).Bacteria present in large numbers in mucus overlying mucosa(pH=7.0).
Exact pathogenic mechanism not known.
Bacterial protease, toxins or ammonia or autoimmune responses may all contribute.
Pathogenesis- Surinder pg.403.
Type A gastritis: atrophic autoimmune gastritis of pernicious anaemia.
H pylori invade the epithelial cell surface to a certain degree
Toxins and LPS may damage the mucosal cells
NH3 produced by the urease activity may also damage the cells
Where numerous, underlying mucosa shows a superficial gastritis known as type B gastritis.

22. H.Pylori is associated with antral gastritis, duodenal(peptic) ulcer disease, gastric ulcers.
Can also cause gastric malignancies, namely ‘Adenocarcinoma’ and gastric B cell lymphoma( mucosa associated lymphoid tissue(MALT) lymphomas).
Stomach cancer, or gastric cancer, refers to cancer arising from any part of the stomach. Stomach cancer causes over 700,000 deaths worldwide per year.[1] Prognosis is poor with a 5-year survival rate of <5 to 15%, largely because most patients present with advanced disease.
Stomach cancer is often either asymptomatic (producing no noticeable symptoms) or it may cause only nonspecific symptoms (symptoms which are not specific to just stomach cancer, but also to other related or unrelated disorders) in its early stages. By the time symptoms occur, the cancer has often reached an advanced stage (see below) and may have also metastasized (spread to other, perhaps distant, parts of the body), which is one of the main reasons for its relatively poor prognosis.
Helicobacter pylori infection is the main risk factor in 65–80% of gastric cancers, but in only 2% of such infections.[5][6] The mechanism by which H. pylori induces stomach cancer potentially involves chronic inflammation, or the action of H. pylori virulence factors such as cag A.
…………………….
Most gastric cancers occur sporadically, whereas 8% to 10% has an inherited familial component.23Gastric carcinoma occasionally develops in families with germline mutations in p53 (Li-Fraumeni syndrome) and BRCA2.19 In 1% to 3% of gastric cancers, germline mutations in the gene encoding the cell adhesion protein E-cadherin leads to an autosomal-dominant predisposition to gastric carcinoma, referred to as hereditary diffuse gastric cancer, that has a penetrance of approximately 70%.19,24–27Huntsman et al24 suggested that identification of the E-cadherin mutation should prompt prophylactic gastrectomy in affected kindreds. Gastric cancer can develop as part of the hereditary nonpolyposis colon cancer (HNPCC) syndrome, as well as part of the gastrointestinal polyposis syndromes, including familial adenomatous polyposis (FAP) and Peutz-Jeghers syndrome.19
An important development in the epidemiology of gastric carcinoma has been the recognition of the association with Helicobacter pylori infection.19 Three independent studies reported a significantly increased risk in subjects who were demonstrated to have had H. pylori infection 10 or more years before the cancer diagnosis.28–30 A follow-up metaanalysis of 42 observational studies carried out by Eslick et al31 showed a significant relationship between H. pylori and gastric cancer (odds ratio [OR], 2.04; CI, 1.69–2.45). H. pylori has subsequently been shown to induce changes in the gastric mucosa and the gastric flora predisposing to the development of carcinoma in humans.19 Furthermore, H. pylori is capable of adhering to the Lewis blood group antigen, and may be an important factor facilitating chronic infection and the subsequent increased cancer risk observed in patients with blood group A phenotype.19
Other factors associated with an increased risk of gastric cancer include chronic atrophic gastritis (eg, pernicious anemia, toxic and dietary agents, previous gastric surgery with bile reflux), hypertrophic gastropathy 
Adenocarcinoma (adeno-, "gland" and karkin(o)-, "cancerous" and -oma, "tumor") (/ˌædɨnoʊkɑrsɨˈnoʊmə/; plural adenocarcinomas oradenocarcinomata /ˌædɨnoʊkɑrsɨˈnoʊmɨtə/) is neoplasia of epithelial tissue that has glandular origin, glandular characteristics, or both. 
……………………………
Lymphoma is a type of blood cancer that occurs when B or T lymphocytes,[1] the white blood cells that form a part of the immune system and help protect the body from infection and disease, divide faster than normal cells or live longer than they are supposed to. Lymphoma may develop in thelymph nodes, spleen, bone marrow, blood or other organs[2] and eventually they form a tumor.[1]
Primary gastric lymphoma (lymphoma that originates in the stomach itself)[1] is an uncommon condition, accounting for less than 15% of gastric malignancies and about 2% of all lymphomas. However, the stomach is a very common extranodal site for lymphomas (lymphomas originating somewhere else with metastasis to stomach).[2] It is also the most common source of lymphomas in thegastrointestinal tract.[3]
Risk factors for gastric lymphoma include the following:
Helicobacter pylori[5]
Long-term immunosuppressant drug therapy
HIV infection

23. Laboratory diagnosis Endoscopy and biopsy Chakraborty363
Gastroscopy is a small part in endoscopy. Where endoscopy looks at all the structures of the human body from joint spaces to the lower intestines, gastroscopy only involves the upper GI tract.
2. Endoscopy may involve incisions made for an artificial orifice, and gastroscopy utilizes the natural opening: the mouth.
3. Gastroscopy procedures are accomplished with local anaesthesia and sedation, whereas endoscopy may require general anaesthesia.
Rapid urease test, also known as the CLO test (Campylobacter-like organism test), is a rapid test for diagnosis of Helicobacter pylori. The basis of the test is the ability of H. pylori to secrete the urease enzyme, which catalyzes the conversion of urea to ammonia and carbon dioxide.
The test is performed at the time of gastroscopy. A biopsy of mucosa is taken from the antrum of the stomach, and is placed into a medium containing urea and an indicator such as phenol red. The urease produced by H. pylori hydrolyzes urea to ammonia, which raises the pH of the medium, and changes the color of the specimen from yellow (NEGATIVE) to red (POSITIVE).
Read more: 

24. Rapid urease test: A biopsy sample is placed into a urea broth and an indicator such as phenol red. The urease produced by H. pylori hydrolyzes urea to ammonia, which raises the pH of the medium, and changes the color of the specimen from yellow (NEGATIVE) to red (POSITIVE).
Microscopy: Gram / Giemsa / Warthin-Starry silver stain
H.Pylori in gastric mucosal impression smear(SilverStaining)

25. Culture:
Histology more sensitive than culture.
Usually not done.
Only done when sensitivity tests or typing is required.
Tissue biopsy material is collected in Stuart transport media and cultured in selective media.
Antigen detection
Faecal antigen detection by ELISA(Commercial-Meridian Diagnostic, USA).
PCR.
Urea breath test - samples of breath air are collected by having the patient blow into a tube before and 30 min after ingestion of 13C-labeled urea, rapid, noninvasive, for assessing response 4-8w post therapy, expensive but non invasive!!

26. Treatment
PPI proton pump inhibitors therapy omeprazole / lansoprazole +amoxicillin + clarithromycin or metronidazole + Bismuth subsalicylate
Clarithromycin: An acid resistant macrolide.
Bismuth subsalicylate: It is deterimental to the bacteria and also protect the ulcer from further harm the gastric acid.

27. Reference: