Approach to Diarrhoeal illness

Question 1

acute diarrhoea

Answer 1

<14 days

Question 2

persistent diarrhoea

Answer 2

more than 14 days

Question 3

chronic diarrhoea

Answer 3

more than 30 days

Question 4

blood tests

Answer 4

haemoglobin
urea and creatinine
electrolytes - sodium, K, magnesium
CRP
iron stores

Question 5

causes of acute infectious watery diarrhoea

Answer 5

norovirus
rotavirus
campylobacter spp.
eschericia coli

Question 6

causes of acute infectious inflammatory diarrhoea

Answer 6

clostridium deficile
escherichia coli
shigella spp.

Question 7

positive stool sample

Answer 7

stool samples are only positive in 1-5% of cases

Question 8

diarrhoea in pregnant women

Answer 8

listeria monocytogenes?

Question 9

developed symptoms within six hours

Answer 9

performed toxins - staph aureus?

Question 10

reheated rice

Answer 10

bacillus cereus

Question 11

post ingestion of pork products

Answer 11

yersinia spp. (usually a few days incubation)

Question 12

recent antibiotic therapy or hospitalisation

Answer 12

clostridium difficile

Question 13

acute diarrhoea mananegemtn

Answer 13

most cases are self limiting and do not require antibiotics
fluid and electrolyte replacement

Question 14

consider antibiotics if:

Answer 14

severe disease
immunosuppressed
significant comorbidities

Question 15

anti diarrhoeals

Answer 15

not recommended as first line therapy

Question 16

acute diarrhoea oral rehydration solutions (ORS)

Answer 16

SGLT-1 protein usually unaffected
relies on cotransport of sodium and glucose
pulls water into vascular system
low osmolarity solution recommended

Question 17

what to test for in persistant diarrhoea

Answer 17

reasonable to test for parasitic organisms if not already done
often need to specifically request ‘ova and parasite’ exam

Question 18

types of parasites that might be the cause of persistent diarrhoea

Answer 18

giardia (lol sam)
cryptosporidium
entamoeba histolytica
often associated with travel

Question 19

causes of chronic diarrhoea

Answer 19

resource limited places: chronic bacterial Orr parasitic infections
resource rich areas: functional disorders, inflammatory bowel disease, malabsorption syndromes

Question 20

nature of secretory chronic diarrhoea

Answer 20

watery, voluminous bowel movements, often with nocturnal symptoms and a lack of response to fasting
patients often have electrolyte disturbances and dehydration

Question 21

nature of secretory chronic diarrhoea

Answer 21

watery, voluminous bowel movements, often with nocturnal symptoms and a lack of response to fasting
patients often have electrolyte disturbances and dehydration
may be caused by medications such as lactulose, laxatives, magnesium supplements or ingestion of alcohol sugars (sorbitol, mannitol, xytol)

Question 22

nature of malabsorbtive chronic diarrhoea

Answer 22

the lack of uptake of luminal contents
coeliac disease, pancreatic insufficiency
small intestinal bacterial overgrowth which is associated with a variety of diseases eg. systemic sclerosis, diabetes, cirrhosis and portal hypertension, strictures, previous surgeries etc.

Question 23

nature of inflammatory chronic diarrhoea

Answer 23

not just IBD
microscopic colitis is divided into two subgroups
- lymphocytic colitis with has a lymphocyte predominant infiltrate
- collagenous colitis also features a sub epithelial collagen band
chronic inflammation in both leads to epithelial destruction

eosinophilic enteritis can be associated with other conditions like EO or atopic conditions. patients may need steroid therapy

Question 24

appropriate investigations for chronic diarrhoea

Answer 24

bloods for electrolytes, serum albumin and nutrient deficiencies
measurement of stool sodium osmotic gap
faecal elastase
faecal calprotectin to evaluate for IBD
faecal fat measurement is rarely done
gastroscopy and colonoscopy

Question 25

coeliac disease

Answer 25

an immune mediated enteropathy against dietary gluten

Question 26

patients with coeliac disease generate antibodies against

Answer 26

gliadin (which makes up gluten) and to tissue transglutaminase

Question 27

what happens after ingestion of gluten in coeliac people

Answer 27

mucosal immune response 1. increased intraepithelial lymphocytes 2. villous atrophy 3. crypt hyperplasia

Question 28

diagnosis of coeliac disease

Answer 28

sensitivity and specificity of the anti-TTG antibody assay is very high duodenal biopsy remains gold standard because you can evaluate the severity of mucosal changes

Question 29

symptoms of coeliac disease

Answer 29

can be very non-specific diarrhoea abdo pain and bloating unexplained iron deficiency neurological symptoms dermatitis herpetiformis

Question 30

coeliac disease management

Answer 30

lifelong adherence to a strict gluten free diet replace nutrient deficiencies prevention of bone loss vaccination monitoring for refractory disease and complications

Question 31

churns disease

Answer 31

a chronic inflammatory disease of the GI that can affect any part from mouth to anus most typically characterised by transmural inflammation

Question 32

ulcerative colitis

Answer 32

a chronic inflammation disease of the colon that starts in the rectum and can extend proximally to involve all segments of the colon most typically characterised by mucosal inflammation only

Question 33

pathogenesis of IBD

Answer 33

genetics environment - smoking, emulsifiers microbiome - loss of diversity barrier defects - bacteria more easily more across the gut wall causing inflammation innate and adaptive immune dysfunction - immune cells become less tolerant and produce more pro inflammatory cells

Question 34

clinical features of chrons disease

Answer 34

diarrhoea for more than 6 weeks abdo pain weight loss perianal fistulas systemic symptoms including malaise, anorexia, feverr

Question 35

clinical features of ulcerative colitis

Answer 35

blood in stools rectal urgency tenesmus mucous in stools nocturnal defecation crampy abdo pain left iliac fossa pain

Question 36

which IBD disease has fistulas

Answer 36

chrons

Question 37

which IBD disease has skip lesions

Answer 37

chrons

Question 38

which IBD disease affects colon only

Answer 38

ulcerative colitis chrons is anywhere from mouth to anus

Question 39

which IBD disease has bloody diarrhoea

Answer 39

both but chrons is often non-bloody

Question 40

thickness of mucosal damage in IBD diseases

Answer 40

UC - involves the lining (mucosa) only chrons - transmural

Question 41

impact of smoking on development of IBD disease

Answer 41

chrons - higher risk UC - lower risk

Question 42

which IBD disease has cobblestone mucosa on colonoscopy

Answer 42

chrons

Question 43

medical therapies for IBD

Answer 43

steroids immunomodular drugs biologic drugs (infliximab, adalimumab, vedolizumab, ustekinumab)

Question 44

surgical therapies for IBD

Answer 44

limited small bowel resections in churn's disease colectomy for severe ulcerative colitis with restorative pouch perianal abscess drainages and fistulotomy

Question 45

irritable bowel syndrome

Answer 45

chronically recurring abdo pain or discomfort and altered bowel habits often co-exists with depression and anxiety and involves significant impairment to quality of life

Question 46

symptoms of irritable bowel syndrome

Answer 46

abdo pain bloating excess flatulence diarrhoea constipation

Question 47

things that are *not* features of IBS

Answer 47

bloody stools weight loss fever signs of systemic inflammation

Question 48

subtypes of irritable bowel syndrome

Answer 48

IBS-C: constipation predominant IBS-D: diarrhoea predominant IBS-M: mixed type IBS-U: undefined

Question 49

IBS syndrome management

Answer 49

largely lifestyle based low FODMAP diet for diarrhoea predominant symptoms laxative and increased soluble fibre for constipation dominant symptoms anti-spasmodics CBT