101. Diarrhoea Flashcards
(30 cards)
Where are the most fat soluble vitamins absorbed?
Ileum
Where is vitamin B12 and bile acid absorbed?
Terminal/ Distal ileum
What are the 4 histological layers of the gut?
Lumen out: Mucosa, submucosa, muscularis propria and serosa
What cells are the simple columnar epithelia in the gut made of?
What feature do they have on their surface?
Enterocytes
Microvilli
What cells are found in the mucosa of the GIT?
Surface to base: Enterocytes, goblet cellsm endocrine cells, paneth cells and stem cells
What is the function of goblet cells?
Produce mucous
What is the function of paneth cells?
Gut defence: produce lysozymes and defensins
Which part of the mucosa in the GIT contains capillaries, nerves and lymphatics?
The lamina propria
What are the two layers of the muscularis propria in the GIT?
Inner circular smooth muscle
outer longitudinal smooth muscle
Where are Brunners Glands found and what do they do?
In the proximal duodenum, in submucosa
Secrete alkaline HCO3- mucus to protect the linig from the acid
Where are Peyers pathes found and what is their function?
In the ileum in submucosa and lamina propria - large lymphoid aggregates to sample gut contents
What is the definition of diarrhoea?
3 or more loose or watery stools (taking the shape of the container) in a 24 hour period
How long is
1) acute diarrhoea
2) persistent diarrhoea
1) For 7 days
2) Up to 14 days
What is osmotic diarrhoea?
When there is a hypertonic substance/ environment in the lumen drawing water into the gut, therefore there is an osmole gap
What are some of the causes of osmotic diarrhoea?
Ingestion of a non-absorbable substance, generalised malabsorption or a specific absorptive defect
What is secretory diarrhoea?
When tehre is both intestinal secretion or fluid and decreased absorption = large volumen diarrhoea, there is not osmole gap
What are some of the causes of secretory diarrhoea?
Enterotoxins, hormones, bile salts, fatty acids and some laxatives
What is inflammatory diarrhoea?
Diarrhoea due to damage to the intestinal mucosal cells/lining resulting in loss of fluid/blood
What are some causes of inflammatory disease?
Some infective conditions and inflammatory bowel conditions such as IBS, Crohns and Ulcerative colitis
What is the leading cause of gastroenteritis in children?
Rotavirus
What is the most common virus causing diarrhoea in closed communities?
Norovirus
What is the 1st and 2nd most common cause of travellers diarrhoea?
1) ETEC - enterotoxigenic E.coli
2) Campylobacter
What increases the risk of developing diarrhoea from Clostridium difficile?
ABx use in hospital admissions and PPI’s
What is the most common cause of parasitic diarrhoea in developed countries?
Giardiasis
