Diarrhoea

Question 1

definition of diarrhoea

Answer 1

more than 200g per day
loose consistency
frequency increased

Question 2

Acute vs Chronic diarrhoea causes

Answer 2

Acute - baceterial (ecoli, campylobacter), virus (norovirus), parasitic
Chronic - many different causes, can be grouped into mechanism (inflmatory, osmotic, secretory, fatty)

Question 3

How does campylobacter, giardia and enterotoxigenic e.coli cause diahorrea by different mechanisms

Answer 3

Campylobacter - INFLAMMATORY - causes mucosal inflammation - exudate released
Giardia - OSMOTIC - mild villous damage, which leads to malabsorption of carb and then this draws fluid in
E coli - SECRETORY - toxin stimulates excess fluid secretion

Question 4

Inflammatory, osmotic, secretory, fatty diahorrea

Answer 4

Inflammatory - damaged epithelium, releases exudate
Osmotic - osmotically active compounds draw fluid into lumen (e.g damage to villous, malabsorption, more solutes in lumen)
Secretory - stimulation of excessive fluid secretion
Fatty - fat malabsorption (damage to cells producing enzymes)

Question 5

Chronic diahorrea - Inflammatory - causes

Answer 5

Causes

• Inflammatory bowel disease
• diverticiulitis (inflamed pouches in bowel)
• small intestinal bacterial overgrowth - bacteria causes direct inflammation of tnereocytes
• radiation colitus
• ischameic coloitis
• colon cancer

Question 6

Chronic Diahorrea - osmotic diarrhoea - causes

Answer 6

Carb malabsorption - lactose intolerance, irritable bowel syndrome
Coeliac disease - villous abnormality
Small intestinal bacterial overgrowth - malabsorpion of proteins, carbs, fat ad other osmoticaly acitve byproducts - attracts fluid into lumen
Laxative abuse

Question 7

Chronic Diahorrea - Secretory diarrhoea - causes

Answer 7

Terminal ileal resection - bile acid malabsorption - surgery, bile acids enter colon and get damage
Cholecystectomy - bile flow continuous into small intestine
Microscopic colitis
Diverticulitis
Neruoedncorine tumours - rare - hormones that can drive water secretion
Small intestinal bacterial overgrowth - unabsorbed food products and bile acids can stimulate secretory cells in the colon
Disordered motlity - irritable bowel syndrome, post vagotomy diarrhoea, diabeteic aunomic neuropathy, hyperthyrodisim
Colon cancer
Laxative abuse

Question 8

Chronic Diahorrea - Fatty diarrhoea - causes

Answer 8

Pancreatic exocrine insufficiencey - inadequate pancreatic enzymes
Bile acid malabsorption - inadequate amounts of bile acids
Small intestinal bacterial overgrowht - deconjugation of bile acids, impared micelle formation - impaired fat digestion and absorpiton
Coeliac disease - muscosal disease
Short bowel syndrome - not enough mucosal surface

Question 9

Small intestinal bacterial overgrowth causes, symptoms

Answer 9

What - Excessive bacteria in small intestine
Symptoms - bloating, flatulence, abdominal discomfort, diarrhoea, steatorrhoea, malabsoprtion
Cause - imparied motility (migrating motor complex prevents clearning) - diabetes
Anatomic disorders - blockage of SI - stricutures, blind loops, diverticula
-metabolic, immune

Question 10

SIBO mechanisms

Answer 10

Maldigestion - bacteria deconjugates bile acids leading to impared micellular formation and fat digestion

• Bacterial degradation of carbs in intestinal lumen, which also produces asmotically active byproduts
• bacterial degreation of bacteria precursos in lumen
• damages enterocytes by direct adherence, prodcuing enterotoxins and enzymes

Question 11

What is malabsorbed with SIBO

Answer 11

-bile, fats, protein, vit b12 - bacteria competes for this, carbs

Question 12

what types of Diahorrea in SIBO

Answer 12

Fatty diarrhoea - deconjugation of bile acids - impaired micelle formation, impaired fat digestion and absorption
Inflammatory - direct inflammation to enterocytes due to damage
Osmotic dihorrea - malabroption of proteins, carbs, fats and other osmotically active byproducts by bacterial metabolsim, deconjucated bile acids inhibit carb transporters
Secretory - unabsorbed food products and bile acids sitmulate secretory cells in colon

Question 13

Melena - associated with

Answer 13

bleeding form upper GI tract

Question 14

Delayed vomiting after eating suggests

Answer 14

Could be a pyloric obstruction

Question 15

What can be done for ulcer, fibrosis/scaring with melena to treat ? delayed vomiting

Answer 15

endoscopic ballon dilation - to open where there is a stricture or damage, but also need to treat ulcer
can do vagotomy

Question 16

what happens with rapid gastric emptying of digested food particles

Answer 16

high osmotic load into small intestnine, which draws large colume of fluid into jejunum
-OSMOTIC diarrhoea

Question 17

What can a vasectomy lead to

Answer 17

• rapid entering of contents into stomach - depending on where
• increased small bowel motlitiy - can reduce this with drugs such as loperamide

Question 18

what is an ileostomy

Answer 18

small intestine close to skin, and contains a bag to empty fluid into

Question 19

Crohns disease

Answer 19

inflammatory - can occur anywhere on colon, causes fibrosus which can lead to strictures - skinnier areas

Question 20

what could happen with terminal ilium removal?

-how to treat?

Answer 20

could get reduced reuptake of bile salts via enterohepatic circulation

• fat malabsoption - steatorrhoea
• bile salts in colon - stimulate water and electrolyte secretion i.e secretory diarrhoea
• more irritating - secretory
• more fatty - steatorrhoea
• can treat with cholestryamine - drug that binds bile

Question 21

Short bowel syndrome

• what will be malabsrobed
• what are adaptive processes
• management

Answer 21

small bowel surgery

• malabsorption of vit, min, water, electrolytes, proteins, fats, carbs, bile
• if have colon and iliocacel valve then do better - colon resorbs water and iliocacel valve can slwo down transit to colon

Adaptive process - villiu hypertorphy
-colon increases absorpative capacity

Management - dietary - low osmotic load
-anti-motlility drugs
-acid suppressant medications
cholestryamine
total parenternal nutrtion