diarrhoea

Question 1

causes of diarrhoea

Answer 1

viral/bacterial infection
drugs
IBS/IBD

Question 2

4 types of diarrhoea

Answer 2

osmotic
secretory
chronic and inflammatory
dysfunctional

Question 3

What is osmotic diarrhoea caused by?

Answer 3

decreased absorption or increased secretion of water and electrolytes by intestinal epithelium
too much water into bowel

Question 4

main causes of osmotic diarrhoea

Answer 4

bacterial enterotoxins (cholera, E. Coli)
luminal secreting agents (bile acids, laxatives)
circulating secreting agents (hormones, drugs, poisons)
medical problems (Addison’s disease, carcinoid tumour, vipoma)

Question 5

What malabsorption syndromes is osmotic diarrhoea common in?

Answer 5

lactose intolerance

Celiac disease

Question 6

How to distinguish between osmotic and secretory diarrhoea?

Answer 6

calculating the fecal osmotic gap

Question 7

What is the stool osmotic gap?

Answer 7

difference between Na and K ions in the stool

Question 8

What is normal osmolarity?

Answer 8

50 - 100 mOsm/kg

Question 9

What osmolarity indicated secretory diarrhoea?

Answer 9

< 50 mOsm/kg

Question 10

osmolarity for osmotic diarrhoea?

Answer 10

> 100 mOsm/kg

Question 11

secretory/osmotic affected by fasting?

Answer 11

osmotic decreases in severity with fasting

osmotic load removed

Question 12

What causes chronic/inflammatory diarrhoea?

Answer 12

inflammation in the bowel mucosa causes decreased fluid resorption

Question 13

inflammatory diarrhoea in what diseases?

Answer 13

CD
UC
intestinal infections - clostridiodies difficile or shigella

Question 14

What’s in stool in inflammatory diarrhoea?

Answer 14

blood
WBCs
mucous

Question 15

What is functional diarrhoea?

Answer 15

chronic or recurrent diarrhoea not explained by structural or biochemical abnormalaties

Question 16

most common functional diarrhoea

Answer 16

IBS

Question 17

What could be a cause of functional diarrhoea?

Answer 17

alterations in microbiome of intestine and rapid transit time of contents through GIT

Question 18

cause of diarrhoea due to impaired intestinal motility

Answer 18

abnormal intestinal motility where transit time is accelerated and absorption is decreased

Question 19

exudative diarrhoea?

Answer 19

caused by drugs that cause imflammation and ulceration in the intestine

Question 20

microscopic colitis cause of diarrhoea

Answer 20

drugs cause thick submucosal band of collagen in intestine

results in watery diarrhoea

Question 21

Most common cause in adults?

Answer 21

campylobacter

Question 22

most common cause in children?

Answer 22

rotavirus

Question 23

Most common cause of travellers diarrhoea?

Answer 23

enterotoxigenic E coli

Question 24

how long until symptoms?

Answer 24

72 hours

Question 25

What indicates bacterial toxins are being produced?

Answer 25

onset of 6 hours after meal

Question 26

How long does it last?

Answer 26

short duration | 4 - 7 days

Question 27

When to refer?

Answer 27

``` >72hrs healthy adult >48hrs elderly >24hrs diabetics severe vomiting and fever change in bowel habit blood/mucus suspected drug reaction alternating constipation/diarrhoea in elderly (fecal impaction) ```

Question 28

What types are self limiting?

Answer 28

acute infective and teaveller's

Question 29

What should be given in moderate/severe Traveller's?

Answer 29

antibiotics

Question 30

4 examples of antimotility agents

Answer 30

codeine phosphate loperamide diphenoxylate kaolin/opiate preparations

Question 31

Can antimotility agents be given to children?

Answer 31

no | risk of respiratory depression or paralytic ileus

Question 32

when to avoid antimotility agents

Answer 32

in severe gastroentritis

Question 33

What is useful with antimotility agents in Traveller's diarrhoea?

Answer 33

antibiotics

Question 34

What is combined with antimotility agents for severe diarrhoea/dysentry?

Answer 34

antimicrobial therapy

Question 35

2 opioid receptor agonsits used for diarrhoea

Answer 35

loperamide | diphenoxylate

Question 36

Where does loperamide work?

Answer 36

mu opioid receptors in the myenteric plexus of the large intestine

Question 37

How does loperamide work?

Answer 37

reduces peristalsis increases transit time enhances water/electrolyte reabsorption reduces gut secretions

Question 38

How long does loperamide take to work?

Answer 38

1 hour

Question 39

loperamide dose

Answer 39

4mg initially | followed by 2mg as needed

Question 40

side effects of loperamide

Answer 40

free from CNS side effects | CNS depression in overdose

Question 41

What is diphenoxylate used in combination with?

Answer 41

atropine

Question 42

age for diphenoxylate

Answer 42

over 13 years

Question 43

What is diphenoxylate metabolised to?

Answer 43

difenoxin

Question 44

action of dyphehnydramine

Answer 44

slows down contractions in the intestine

Question 45

Side effects of dyphenhydramine

Answer 45

euphoria - abuse | dependence in prolonged use

Question 46

Why is atropine given with diphenhydramine?

Answer 46

reduces abuse

Question 47

combination produce with dihpenhydramine and atropine

Answer 47

Lomotil

Question 48

Lomotil dose

Answer 48

``` 4 times a day 4 tabs (2.5mg) followed by 2 tabs every 6 hours ```

Question 49

Why is operamaide the drug of choice?

Answer 49

don't need to add atropine doesn't cross BBB no abuse

Question 50

4 examples of bulking agents

Answer 50

wheat bran isphaghula husk methylcellulose sterculia

Question 51

What do bulking agents do?

Answer 51

control fecal consistency (in IBS, colostomy, ileostomy)

Question 52

Are bulking agents recommended for acute diarrhoea?

Answer 52

no

Question 53

what meds are not absorbed as well with antidiarrhoeal drugs?

Answer 53

``` slowly absorbed drugs - antiepileptics, m/r formulations antidiabetics anti-coagulants anti-malarials oral contraceptives ```

Question 54

what to eat/drink with diarrhoea

Answer 54

clear fluids | light, easily digested foods

Question 55

what to avoid

Answer 55

high sugar drinks | milk

Question 56

why avoid milk?

Answer 56

temporary lactose intolerance due to damage by infecting organisms to lining of intestine makes diarrhoea worse