Malabsorption and Small Intestine Disease Flashcards
What are the functions of the small intestine?
Digestion
Absorption
Endocrine and neuronal control functions
What is the digestive function of the small intestine?
The breaking down of food into its components
Components that can then be absorbed
What is the absorption function of the small intestine?
The passage of nutrients into the blood stream
Describe the structure of the small intestine
3 pars Duodenum Jejunum Ileum Large surgace area Covered in villi Villi covered in microvill
Does the large intestine frequently turn over its cells?
Yes very
Why is the rarity of malignancy of the small intestine so surprising?
Because of the high cell turnover rate
Describe the bacterial population in the small intestine
Low bacterial population
Why do most bacterial not survive in the small intestine?
Because bile is incredibly toxic
Where does digestion commence?
In the stomach
How is fat digested?
By pancreatic lipase
Absorption of glycerol and free FA
Via lacteal and lymphatic system
Hows are carbohydrates absorbed?
Pancreatic amylase
Breakdown to disaccharides
Final digestion by brush border
What are the symptoms of general malnutrition?
Weight loss
Increased appetite
Diarrhoea
Fatigue
What causes steatorrhea?
Fat malabsorption
What is steatorrhea?
High fat content in stools
Stools are lens dense and float
How does steatorrhea present?
Floating stools
Foul smelling
May leave an oily mark
What are signs of general malnutrition?
Signs of weight loss
Low of falling BMI
What are signs of iron deficiency?
Anaemia
Painful tongue
Angular stomatitis
What are some non-specific signs in malnutrition?
Clubbing
Scleorderma
Apththous ulceration
What is aphthous ulceration?
Mouth ulcers
What investigations are done for the small bowel?
Small bowel biopsy Small bowel study White cell scan CT scan MRI enterography Capsule enteropraphy
What can clubbing be a sign of in small bowel disease?
Crohn’s
Coeliac disease
What is a White cell scan?
- WBC are removed and tagged with radioactive material
- Injected back into locate the site and extent of inflammation
Is coeliac disease common or uncommon?
Common
Why is coeliac disease considered to be an iceberg?
Because so many people go undiagnosed
What are coeliacs sensitive to?
The Gliadin fraction of gluten
Where is gliadin (of gluten) found food wise?
Wheat
Rye
Barley
Where is the gold standard of coeliac diagnosis?
Distal duodenum biopsy
What does gliadin do in coeliac?
Produces an inflammatory response
How is the inflammatory response in coeliac thought to be mediated?
Via tissue transglutaminase
What is the pathological appearance of coeliac?
Partial or subtotal villous atrophy
Increased intra-epithelial lymphocytes
What are the potential complications of coeliac?
o Refractor coeliac disease o Small bowel lymphoma - rare o Oesophageal carcinoma o Colon cancer o Small bowel adenocarcinoma
How is coeliac diagnosed?
Distal duodenal biopsy
Serology
IgA
Total plasma IgA
What is the difference between partial, subtotal and total villous atrophy?
Partial - shortened villi
Subtotal - the lining is flat with extended glands
Total - the lining is down to a thin line
What is the treatment for coeliac?
Withdraw gluten
Refer to a state registered dietician
What are causes of malabsorption?
Inflammation Infection Whipples Disease Impaired gut motility Iatrogenic Pancreatic problems Infiltration Tropheryma Whippelii
What inflammatory diseases can cause malabsorption?
Coeliac
Crohn’s
What pancreatic conditions can cause malabsorption?
Chronic pancreatitis
CF
What skin condition is associated with coeliac
Dermatitis Herperiformis
Diagnostic procedure for coeliac
Distal duodenal biopsy
Histological finding of coeliac disease
Partial or total villous atrophy
Commonest treatment for coeliac disease
Removal of gluten from diet
Cause of coeliac disease
Autoimmune inflammatory response to harmless gliadin fraction of gluten
