Diseases of the GI tract

Flashcards related to Glenn Gibson's lecture on the diseases of the GI tract, including inflammatory bowel disease, antibiotic associated diarrhea, irritable bowel syndrome, bowel cancer, gastroenteritis, obesity, and autistic spectrum disorders.

What are the learning objectives related to diseases of the GI tract?

Understanding of human gut anatomy, differences between probiotics and prebiotics, and descriptions of different gut disorders including symptoms, recognition, and the role of the gut microbiome.

What are some examples of facets of gut health?

Immunity, pathogen inhibition, antibiotic-associated diarrhea, inflammatory bowel diseases, atopic issues, digestive cancers, irritable bowel syndrome, constipation, diarrhea, bloating, cognitive interactions, obesity, metabolic syndrome

What is the main component of the mucosa layer?

Epithelial lining

What tissues make up the submucosa layer?

Dense connective tissue with blood vessels and glandular tissue

What are the primary functions of the small intestine?

site of terminal food digestion, nutrient absorption and endocrine secretion.

What is a goblet cell?

Unicellular gland found in the lining of the intestine and respiratory tract.

What do goblet cells secrete?

Secrete mucus (mucin - glycoprotein)

What is the function of the large intestine (colon)?

Site of absorption, excretion. Main microbial reservoir in the body.

What are the major impacts of microbiota on human physiology?

Immune system, digestive function, metabolism

What disorders are associated with microbiota?

IBD (UC, CD), AAD, IBS, colorectal cancer, PCI, Gastroenteritis, obesity, autism

What is a defining characteristic of the microbiota of the stomach?

Low pH

What is the transit time in the small intestine?

Transit time is 2-4h

What is the length of the large intestine?

150cm in length

What is unique about the microbiota of the large intestine?

The most heavily colonized organ in the human body

How many more gut microbes do we have than human cells?

10x more gut microbes than human cells

What percentage of our immune system resides in the gut?

Approximately 70%

What represents the most metabolically active organ in the body?

The gut microbiota

What are some methods of therapeutic modulation of the gut?

Fecal transplant, Antibiotics, Probiotics, Prebiotics, Dietary modification

What is an example of a target for therapeutic modulation?

Pathogen resistance

Where do gut bacteria come from initially?

Birth: initial colonisers

What bacteria predominate when breast fed?

Bifidobacteria

What occurs during carbohydrate fermentation that can be seen in breath or flatus?

H2, CO2, H2S

What occurs during protein fermentation that can be seen in blood, faeces, or urine?

Ammonia, Amines, Phenols

What is the function of acetate in the body?

Systemic energy source

What is the function of Butyrate in the body?

Energy for colonocytes

What is the function of Propionate in the body?

produced by gut bacteria from fermenting fiber. It Reduces cholesterol biosynthesis and ldl cholestrol

What are some positive impacts of gut bacteria?

Inhibition of harmful bacteria, immunomodulation, digestion/ absorption of food ingredients & minerals, SCFA production, vitamin synthesis, phytochemical conversions

What are some negative impacts of gut bacteria?

Diarrhoea, infections, toxin production, intestinal putrefaction, ulcers, digestive cancers, IBD, IBS, Obesity, ASD’s

What does IBD stand for?

Inflammatory bowel disease

What is the name of a group of disorders that cause the intestines to become inflamed?

Inflammatory bowel disease

What are some common symptoms of IBD?

abdominal cramps and pain, diarrhoea, weight loss and bleeding

What are the clinical features of Ulcerative colitis?

Bloody diarrhoea, pain, fever, weight loss

What are some treatments for Ulcerative colitis?

sulphasalazine, adrenal steroids, colectomy

What do sulphate-reducing bacteria use to produce H2S?

Use SO4 (or SO3 etc) to produce H2S

What can H2S lead to in the gut?

Toxic levels - worsen ibs, pain, bloating, gut immune system impairment, and increased inflammation.

What is Crohn's Disease?

Chronic inflammatory disorder

What are some symptoms of Crohn's Disease?

Fever, pain, tiredness, diarrhoea

What is AAD?

Antibiotic associated diarrhoea

Why does antibiotic associated diarrhoea occur?

Because of a compromised commensal gut flora

What is the bacteria that causes Pseudomembranous colitis (PMC)?

Clostridium difficile

What antibiotics are most frequently implicated in Clostridium difficile infections?

Ampicillin, clindamycin, cephalosporins

What is the treatment for Clostridium difficile?

Vancomycin and anion resins

What is a classic antibiotic that causes Pseudomembranous colitis?

Clindamycin

What is Irritable bowel syndrome (IBS)?

A common gut complaint (up to 20%)

What are possible risk factors for developing IBS?

Stress or gut?

What are some Variable symptoms of IBS?

abdominal pain, bloating; and bouts of diarrhoea or constipation or both

What kind of disorder is IBS?

A ‘functional’ disorder (i.e. no tissue damage but function is affected)

How can Candida be controlled in the gut?

Control is with nystatin

What are some Strategies for alleviating the symptoms of IBS ?

Traditional treatment for IBS includes the addition of more fibre to the diet, reduction of stress, anti-spasmotic drugs and tranquilisers

What kind of impact does GOS have on people with IBS?

GOS significantly reduced symptoms such as bloating, flatulence and abdominal pain in IBS sufferers

What is the aetiology of bowel cancer?

Aetiology is unknown, but at least 12 bacterially produced carcinogens are known

What are the Clinical features of bowel cancer?

Changes in bowel habit, bleeding, pain, anorexia, weight loss, symptoms of anemia

What kind of disorder is Pneumatosis cystoides intestinalis (PCI)?

Rare disorder of gas metabolism. gas-filled cysts in the intestinal wall, which can lead to - Bloody stools, diarrhea or constipation, vomiting, abdominal pain, flatulence, and weight loss

What is the pathology of Pneumatosis cystoides intestinalis (PCI)?

gas filled cysts lining the gut wall

What does Gastroenteritis involve?

Mild inflammation of the GI -tract . stomach flu could be caused by bacteria,virus, food poisioning , parasite

What is the cause of Gastroenteritis?

Usually due to transient pathogens from food or water that is contaminated

What are some symptoms of Gastroenteritis?

Nausea and vomiting, Fever, Diarrhea, Loss of appetite, Abdominal pain, Abdominal cramps, Bloody stools

Who wrote the article 'Obesity and gut flora'?

matej bajzer and randy j. seeley

Who wrote the article 'Human gut microbes associated with obesity'?

peter j. turnbaugh

What influence do gut bacteria have on MS?

Influence on hormones involved in satiety (GLP, ghrelin, PYY)

What are the signs of autism?

impairments in social interaction, communication and development of imagination

What bacteria has a link to ASDs?

Clostridium spp.

What costs are associated with ASDs?

treatment, loss of earnings, care, support

What market is interested consumer in according to the digestive health market slide?

Improve your digestive system health

What market is interested consumer in according to the immune support slide?

Improve your immune system/support body defences

What is a probiotic?

Live microorganisms which, when administered in adequate quantities, confer a health benefit to the host’

What kind of bacteria does the gut contain?

The gut contains: ‘+ve’ & ‘-ve’ bacteria (pathogens)

What must probiotics do to be effective?

Contain sufficient live, active ‘good’ bacteria, be stable and viable for the life of the product, survive the stomach acids, provide health benefits, be safe and amenable for human consumption

What types of diarrhea can probiotics help with?

acute infections, antibiotic-associated diarrhea, C. difficile

According to the meta analysis, what is the risk ratio of probiotic use?

0.64 [0.38, 1.07]

Who wrote the article 'Using Probiotics to Flatten the Curve of Coronavirus Disease COVID-2019 Pandemic'?

David Baud, Varvara Dimopoulou Agri, Glenn R. Gibson, Gregor Reid and Eric Giannoni

What are prebiotics?

a substrate that is selectively utilized by host microorganisms conferring a health benefit

What is the key criteria that needs to be demonstrated for any prebiotics?

Selectivity

What does 'activity(ies)' mean for a prebiotic?

meaning a metabolic profile(s), info about body chemical balance, molecular signalling, host- microbe interactions

What does 'confer(s)' mean for a prebiotic?

one or a limited number of selectively stimulated beneficial genus(era)/species

What are some bioactivity testing methods used for prebiotics?

Metabolite analysis, Metabonomics, Molecular microbiology method

Where do we find prebiotics?

Human breast milk, Manufactured forms (GOS, lactulose), Some occur naturally (e.g. asparagus, onion, artichoke, banana, leeks, chicory)

What is The prebiotic barrier?

bifidobacteria, Competition for receptors, Various glycolipids, Production of short chain fatty acids acetate, lactate, Competition for nutrients in the gut, Production of anti- microbial agents, Immuno-modulation

What was the effect of prebiotics in infant monkey feed?

Stopped E. coli infection

What of some food products that prebiotics can be found in?

Dairy products, Beverages and health drinks, Spreads, Infant formulae and weaning foods, Cereals, Bakery products , Confectionery chocolates, chewing gum, Savoury product, soups, Sauces and dressings, Meat products , Dried instant foods, Canned foods, Food supplements , Animal feeds, Petfoods