Diarrhoea Flashcards
(60 cards)
1
Q
how serious can diarrhoea be
A
- Common, often mild and self-limiting but potentially serious and life threatening
- second commonest cause of death in children under 5
2
Q
What do patients sometimes mean by diarrhoea
A
- irregular bowel habit
- change in bowel habit
3
Q
What are the red flags for cancer relating to diarrhoea
A
- change in bowel habit
- bleeding
- weight loss
- FH bowel or ovarian cancer
- aged over 50 and for longer than 6 weeks
- anaemia
- abdominal or rectal mass
4
Q
What is the definition of diarrhoea
A
- 3 and more stools a day and loose
5
Q
How much fluid is cycled in the intestinal tract
A
9L of fluid is cycled from the intestinal tract
6
Q
How much fluid is produced in the intestinal tract
A
- 1L of saliva
- 1l of intestine
- 1L of bile
- 2L of pancreas
- 2L of gastric
- 2L of diet
7
Q
How much fluid leaves the intestinal tract
A
- 1.5L in colon
- 3.4 in ileum
- 4 in Jejunum
8
Q
what is absorbed and secreted
A
Absorption
- nutrients
- water
- electrolytes
secretion
- water
- electrolytes
9
Q
How do you take a history of diarrhoea
A
- duration
- type of stool and frequency
- organic features - BO at night, fever, blood
- systemic disease = diabetes, thyrotoxicosis, systemic sclerosis
- H/O pancreatic disease or abdominal surgery
- family history: IBD, malignancy, coeliac
- travel
- dietary indiscretion (include alcohol)
- medication: NSAIDs, antibiotics, PPIs laxatives
10
Q
How do you classify diarrhoea
A
- Acute - less than 2 weeks
- chronic - last longer than 4 weeks
11
Q
What does acute diarrhoea look like
A
- watery
- bloody
- usually mild and self-limiting
12
Q
What does chronic diarrhoea look like
A
- watery
- bloody
- steatorrhoea
13
Q
What is the most common cause of diarrhoea
A
- infection
14
Q
what can cause acute diarrhoea
A
- Look for fever/pain
- dietary indiscretion (few hours)
- viral infection (24-48 hours)
- food poisoning
- travellers diarrhoea (2-5) days
15
Q
How do you treat acute diarrhoea
A
- usually sit it out
- oral rehydration therapy is it is severe
- usually gets better on its own accord
- occasionally consider IV fluids/antibiotics
16
Q
What is acute travellers diarrhoea caused by
- viruses
- parasites
- other bacteria
A
Viruses
- rotavirus
- adenovirus
- noravirus
- Ecoli
Parasites
- G, intestinalis
- C parvum
- I belli
- cyclospora
other bacteria
- Shingella spp
- salmonella spp
- campylobacter spp
- EHEC
- EIEC
- V cholerae
17
Q
what is the most common cause of acute traveller diarrhoea
A
E.coli
18
Q
What is oral rehydration made out of
A
- 1L of water
- 3.5g of sodium chloride
- 2.5g of sodium bicarbonate
- 1.5g potassium chloride
- 20g of glucose
19
Q
How should you consider using IV fluids/antibiotics in in acute diarrhoea
A
- elderly or immunocompromised
- frequent bloody stools
- severe abdominal pain
- temperature - greater than 38.5 degrees
- hypovolaemia
20
Q
Persistent and chronic daiarrhoea needs ..
A
always needs accurate diagnosis and treatment
21
Q
describe what - bloody - water - fatty mean in chronic diarrhoea and what can cause them
A
Watery
- secretory
- osmotic
blood
- colonic disease
- infection
- neoplasia
fatty
- pancreatic
- small bowel
22
Q
What are the two causes of fatty diarrhoea
A
- Pancreatic insufficiency
- small intestinal disease
23
Q
How do you check to see if pancreatic insufficiency is causing fatty chronic diarrhoea
A
Normal red cel folate
- faecal fat - greater than 20g/24 hours
- faecal elastase - measure pancreatic enzyme in the stool
- plain abdominal radiograph/US
- abdominal CT, EUS, MRI, MRCP
- ERCP
24
Q
How do you check to see if small intestinal disease is causing fatty chronic diarrhoea
A
- Low red cell folate
- anti-TTG antibodies
- duodenal/jejunal/TI biopsy
- small bowel imaging - CT, MRE
25
What are clues to infective causes of diarrhoea
Rapid onsent of symptoms are food - greater than 6 hours
- toxin producing organisms = B cerus, S aureus
fever
- invasive bacteria - salmonella, shigella, campylobacter
- enteric viruses
- cytotoxic organisms - c.difficle, E histolytica
blood diarrhoea
- invasive bacteria - salmonella, shigella, campylobacter, E.coli
- amoebic dysentery - travel history
Antibiotics
- C.difficile
26
What drugs can cause chronic diarrhoea
- Alcohol
- antibiotics
- anti-depressants
- anti-hypertensives
- cholesterol lowering agents
- NSAIDs
- oral hypoglycemics - (Biguanides)
- propanol
- laxatives
- PPIs
- Digoxin
27
what can cause osmotic diarrhoea
- non absorbable substance
- high concentration of solute in malabsorption
- specific defect - e.g. disaccharidase deficiency
28
What can cause secretory diarrhoea
- inflammation e.g. IBD
- infection e.g. salmonella
- enterotoxins from e.g. E coli, V cholera
- hormones e.g. neuroendocrine tumours
- bile salts and fatty acids
29
What can cause motility diarrhoea
- thyrotoxicosis
- iBS
- DM
- autonomic neuropathy
30
what is the commonest cause of maldigestion
lactose intolerance
31
what is FODMAP related diarrhoea
- Some patients with IBS type symptoms
- osmotic diarrhoea
- pain and bloating from fermentation of these
```
F - fermentable
O - oligosaccharides
D - disaccharides (e.g. lactose)
M - monosaccharides (e.g. fructose)
P - polyols
```
32
What is Clostridum difficile associated with
- use of broad spectrum antibiotics - (clindamycin, cephalosporins, penicillins, fluoroquinolones)
- use of PPIs
33
Describe Clostridium difficile
- anaerobic gram positive
- spore forming
- made out of toxins A and B
- life threatening infection
34
How is Clostridium difficile transmitted
Faecal - oral route
35
Describe who is affected by C.difficile the most
- associated with antibiotic use
- elderly
- more prominent with patients with IBD
36
What are the severities of C Difficile
- Mild
- moderate
- severe
- complicated
- life threatening
37
Describe the severity of disease C difficile
```
Mild
- 3 stools a day
- normal WCC
treatment
- Oral metronidazole 400mg/8h PO for 10-14d
```
```
Moderate
- 3 -5 stools a day
- raised WCC
treatment
- Oral metronidazole 400mg/8h PO for 10-14d
```
```
severe
- WCC raised
- temperature greater than 38.5 degrees
- raised CR
- abdominal pain or XR acute colitis
Treatment
- oral vancomycin 125mg/6hr PO
```
```
complicated
- hypotension
- partial ileus
- evidence of severe disease on CT
Treatment
- Oral vancomycin and IV metronidazole
```
```
life threatening
- complete ileus or toxic megacolon
Treatment
- oral vancomycin and IV metranidazole
- faecal microbiota transplant
- consider colectomy if toxic megacolon, raised LDH or deteriorating
```
38
How do you investigate diarrhoea (bloods and stool)
Blood tests
- FBC - anaemia
- Inflammatory markers - WCC, Platelets, CRP all raised
- U and Es - dehydration/AKI
- albumin/Ca/P - nutritional status
- haematinics
- TTG antibodies and IgA - coeliacs disease
- TFTs
Stool and other tests
- stool weight
- MC&S, CDT, Cysts, ova, parasites
- faecal calprotectin
- FIT - faecal immunochemical test for Hb) - test for blood in the stool
- faecal elastase
- stool pH/electrolytes/reducing substances
39
How do you investigate diarrhoea with imaging
- Colonoscopy and biopsies
Other imaging
- duodenal biopsy
- small bowel MRI
- video-capsule endoscopy
- cross-sectional imaging
40
How do you prevent diarrhoea
- Hand washing with soap and water
41
Name the common causes of diarrhoea
- Gastroenteritis
- traveller's diarrhoea
- C.Difficile
- IBS
- colorectal cancer
- Crohn's disease
- ulcerative colitis
- coeliac disease
42
Name the less common causes of diarrhoea
- microscopic colitis
- chronic pancreatitis
- bile salt malabsorption
- laxative abuse
- lactose intolerance
- illeal/gastric resection
- overflow diarrhoea
- bacterial overgrowth
43
Name the non GI causes of diarrhoea
- thyrotoxicosis
- autonomic neuropathy
- Addison's disease
- ischaemic colitis
- tropical sprue
- gastronome
- carcinoid
- pellagra
- VIPoma
- amyloidosis
44
Name the causes of bloody diarrhoea
- campylobacter
- shigella/salmonella
- E.coli
- amoebiasis
- colorectal cancer
- UC
- Crohn's
- colonic polyps
- pseudomembranous colitis
- ischaemic colitis
45
Name the cause of mucus diarrhoea
- IBS
- UC
- colorectal cancer
- polyps
46
What can cause frank pus in diarrhoea
- IBD
- diverticulitis
- fistula/abscess
47
What can cause explosive diarrhoea
- cholera
- giardia
- yersinia
- rotavirus
48
What is steatorrhoea
- characterised by flatulence, offensive smell, and floating, hard to flush stools
49
What conditions can cause steatorrhoea
- pancreatic insufficiency
- biliary obstruction
- coeliac disease/malabsorption
50
What should be included the assessment of someone with diarrhoea
- Dehydration
- fever, weight loss, clubbing, anaemia, oral ulcers, rashes, abdominal mass or scars
- goitre or hyperthyroid signs
- DRE for masses or impacted faeces
51
What are the signs of dehydration
- dry mucus membranes
- reduced skin turgor
- capillary refill is greater than 2 seconds
- shock
52
What does faecal elastase test for
- if suspected chronic pancreatitis (malabsorption, steatorrhoea)
53
Why do you use lower GI endoscopy
- look for malignancy and colitis
54
name some lower GI endoscopy that you can use
- flexible sigmoidoscopy and biopsies - if acutely unwell
- full colonoscopy - if more proximal disease
- if normal consider radiology or video capsule
55
What is the management of diarrhoea
- Treat the cause
- if there is a hospital outbreak wards might need closing
- Oral rehydration, better than IV but if there is sustained diarrhoea and vomiting, IV fluids with electrolyte replacement might be needed
- Codeine phosphate 30mg/8h PO or loperamide 2mg PO after each loose stool (max 16mg/d) this reduces stool frequency
- avoid antibiotics unless infective diarrhoea is causing systemic upset
- antibiotics associated diarrhoea may be response to probiotics
56
What medication can you give a patient to reduce diarrhoea
- Codeine phosphate 30mg/8h PO or loperamide 2mg PO after each loose stool (max 16mg/d) this reduces stool frequency
- Should avoid in colitis, may precipitated toxic megacolon
57
How do you manage infective diarrhoea
If no systemic signs -stool culture is not needed
Systemic illness -
- fever greater than 39 degrees, dehydration
- diarrhoea and visible blood for >2 weeks
Then you should admit to hospital
- oral fluids
- direct faecal smear
If polymorphs seen
- Likely - shigella, or camplylobacter or E.coli
- more rarely - C.diff, yersina enterocolitica, salmonella
If non polymorphs seen
- likely - salmonella, E.coli,, C.diff
- culture negative causes - noravirus
special circumstances
- food poisoning outbreak
- travel
- recent antibiotic use
- rectal intercourse
- immunocompromised
- raw seafood ingestion
58
What are the signs of C.difficile
- Fever
- Colic
- Diarrhoea with systemic upset (↑↑CRP, ↑WCC, ↓albumin)
- Colitis (with yellow adherent plaques on inflamed non-ulcerated mucosa – the pseudomembrane) progressing to toxic megacolon and multi-organ failure
59
How do you detect C.difficile
- Urgent testing of suspicious stool (characteristic smell)
- Two-stage process with rapid screening test for C. diff protein (or PCR) followed by specific ELISA for toxins
- AXR for toxic megacolon
60
How do you treat recurrent C.difficile
- fidaxomicin (minimally absorbed oral antibiotics) associated with lower relapse rates
- faecal transplantation
