DIARRHOEA Flashcards
1
Q
Define diarrhoea
A
- Abnormal passage of loose or liquid stool more than 3 times daily
2
Q
What is acute diarrhoea
A
Lasting less than 2 weeks
3
Q
What is chronic diarrhoea
A
Lasting more than 2 weeks
4
Q
What is acute diarrhoea caused by
A
Infection
5
Q
How and why is acute diarrhoea diagnosed under certain circumstances
A
- Flexible sigmoidoscopy with colonic biopsy is performed if symptoms persist and no diagnosis has been made
6
Q
How do we treat acute diarrhoea
A
- Maintain hydration + antidiarrhoeal agents for short-term relief and antibiotics for specific indications
7
Q
Name an antidiarrhoeal agent
A
LOPERAMIDE HYDROCHLORIDE
8
Q
What causes chronic diarrhoea
A
Organic causes:
Associated with changes in organ structure or tissue = symptoms (increased stool weights)
Functional causes:
Condition in which there is no physical cause for symptoms (frequent passage of low volume and weight stools such as IBS)
9
Q
How is chronic diarrhoea distinguished from organic and functional causes
A
Faecal markers of intestinal inflammation
10
Q
What points to an infective cause of diarrhoea
A
Sudden onset of bowel frequency associated with crampy abode pain and fever will point to an infective cause
11
Q
What points to an inflammatory cause of diarrhoea
A
Bowel frequency with loose, blood-stained stools
12
Q
What is STEATORRHEA
A
Passage of pale, offensive stools that float
Accompanied by loss of appetite and weight loss
Excess fat in stools
13
Q
What causes decreased stool consistency
A
- Water
- Microscopic colitis
- Fat (Steatorrhoea)
- Inflammatory discharge
14
Q
How does water reduce consistency of faeces
A
- Large quantities of non-absorbed hypertonic substances in bowel lame draw fluid into the intestines
- Diarrhoea stops when patient stops eating or malabsorptive state is discontinued
a) . Ingestion of non-absorbable substances
b) . Generalised malabsorption so that high conc. of solute (glucose remains in the lumen)
c) . Specific malabropstive defects
15
Q
What is microscopic colitis
A
- Active intestinal secretion of fluid and electrolytes as well as decreased absorption
- Continues even when patient fasts
16
Q
What three things cause microscopic colitis
A
- Enterotoxins (E.coli)
- Bile alts in colon following ileal disease, resection or idiopathic bile acid malabsorption
- Fatty acids in colon following ileal resection
17
Q
What characterises stools in steatorrhoea
A
- Increased gas
- Offensive smell
- Floating hard-to-flush stools
18
Q
What conditions can cause steatorrhoea
A
- Giardiasis
2. Coeliac disease
19
Q
What is giardiasis
A
Infection of intestines by protozoa
20
Q
How does inflammatory discharge effect stool consistency
A
- Damage to intestinal mucosal cells lead to a loss of fluid and blood and defective absorption of fluid and electrolytes
21
Q
Causes of inflammatory discharge
A
- Infective (Salmonella or Shigella)
2. Inflammatory (UC or Crohn’s)
22
Q
Where is infective diarrhoea most common
A
Africa and S. Asia
23
Q
Risk factors for infective diarrhoea
A
- Foreign travel
- PPI or H2 antagonist use
- Crowded areas
- Poor hygiene
24
Q
What virus causes infective diarrhoea in children
A
- Rotavirus - effects nearly ALL children by age of 4
25
What virus causes infective diarrhoea in adults
1. Norovirus
| 2. Campylobacter
26
Other than rotavirus and norovirus, what other viruses can cause infective diarrhoea
1. Adenovirus
| 2. Astrovirus
27
Most common cause of bacterial caused infective diarrhoea
1. Campylobacter jejuni
28
How is campylobacter jejune acquired
Poultry
29
What bacteria are most common in children
1. E.coli
2. Salmonella
3. Shigella spp.
30
What antibiotics can give rise to antibiotic-induced clostridium difficile diarrhoea
1. Clindmycin
2. Ciprofloxacin (Quinolones)
3. Co-amoxiclav (Penicillins)
4. Cephalosporins
31
What kind of bacteria are clostridium difficile
1. Gram-POSITIVE spore forming bacteria
32
What disease can C.diff cause
PSEUDOMEMBRANOUS COILTIS
33
Pathophysiology of pseudomembranous colitis
When normal gut flora die due to antibiotic use for example - resulting in dangerous diarrhoea
34
Risk factors on C.difficile
1. Elderly, antibiotics, long hospital admission, immunocompromised (HIV)
2. Acid suppression can contribute (PPI, H2 receptor antagonist)
35
How is c.diff treated
1. METRONIDAZOLE
2. ORAL ORAL VANCOMYCIN
3. RIFAMPICIN/RIFAXIMIN
4. Stool transplant
5. Stop C antibiotic
36
Parasitic causes of c.diff
1. Giardia lamblia (most common)
2. Entamoeba histolytica
3. Cryptosporidium
37
Clinical presentation of infective diarrhoea
1. Blood (bacterial)
2. Salmonella, E.coli, Shigella = BLOODY STOOLS
3. Vomiting
4. Abdominal cramping
38
What are clinical presentations of viral-caused diarrhoea
1. Fever
2. Fatigue
3. Headache
4. Muscle pain
39
Differential diagnosis of infective diarrhoea
1. Appendicitis, volvulus, IBD, UTI, diabetes mellitus
2. Pancreatic insufficiency, short bowel syndrome, coeliac disease
3. Laxative abuse
40
Blood test results in infective diarrhoea
1. Low MCV or Fe deficiency (coeliac or colon cancer)
2. High MCV if alcohol abuse or decreased B12 absorption (coeliac or Crohn's)
3. Raised EBC if parasitic
4. Raised ESR and CRP indicate infection (Crohn's, UC or cancer)
41
Stool test in infective diarrhoea diagnosis
1. Bacteria, parasites and c.diff (we culture stool)
42
What biopsy do we perform for diagnosing infective diarrhoea
Sigmoidoscopy
43
How is infective diarrhoea treated
1. Oral rehydration and avoid high-sugar drinks in children
2. Anti-emetics (treats vomiting)
3. Antibiotics
4. Anti-motility agents
44
Name an anti-emetic
METOCLOPRAMIDE
45
Name an anti-motility agent
LOPERAMIDE HYDROCHLORIDE
46
Name some PPIs
Lansoprazole
Omeprazole
Pantoprazole
47
When are PPIs given as first line prevention
1. Prevent and treat peptic ulcer disease
2. Symptomatic relief of dyspepsia and GORD
3. Eradication of h.pylori infection with antibiotics
48
Adverse effects of PPI
1. GI disturbances and headaches
2. Increasing gastric pH may reduce body's host defence against infection, slightly higher risk of c.diff
3. PPIs may disguise symptoms of gastric cancer
49
How do PPIs effect elderly
Increased risk of fracture so use with care if osteoporosis is present
50
How does omeprazole effect blood constituents
Reduce antiplatlet effect of clopidogrel
So do not prescribe omeprazole with clopidogrel (use a different one)
51
Example of a H2 receptor antagonist
Ranitidine
52
When are H2 antagonists given
Treat + prevent gastric/duodenal ulcers and NSAID associated ulcers if PPIs are contraindicated
Relieve symptoms of GORD and dyspepsia if mild
53
Adverse effects of H2 antagonists
1. Possible bowel disturbance, headache or dizziness
2. Reduce dose in renal impairment
3. Watch for symptoms of gastric cancer as H2 antagonist can disguise them
54
Name some antacids
Gaviscon
| Peptac
55
When are antacids given
1. GORD disease for symptomatic relief of heartburn
| 2. For short-term relief of indigestion and dyspepsia
56
What is dyspepsia
indigestion
57
How do antacids work
Increase viscosity of the stomach contents which reduces reflux of the stomach acid in to the oesophagus
After reacting with stomach acid they form a floating raft which separates the gastric contents from the gastro-oesophageal junction to prevent mucosal damage
58
Side effect of magnesium in antacids
1. Can cause diarrhoea
59
Side-Erect of aluminium in antacids
Can cause constipation
60
Side-effect of Na and K in antacids
Hyperkalaemia
| Fluid overload
61
What compounds do antacids effect the conc. of
1. ACEI
2. Antibiotics
3. PPIs
4. Bisphosphonates
5. Digoxin
62
Name two anti-motility drugs
1. Loperamide
| 2. Codeine phosphate
63
When are anti motility drugs given
As symptomatic treatment of diarrhoea (IBS)
64
Mechanism of loperamide
Is an opioid but does not penetrate the CNS so has no analgesic effects, just an agonist of the opioid mu-receptor in the GI tract which increases non-propulsive contractions of the gust smooth muscle but reduces peristaltic contractions
2. Slows bowel content movement and anal sphincter tone is increased
More water is absorbed from faeces so stools are hardened
65
Difference between codeine phosphate and loperamide
codeine phosphate has analgesia
66
Adverse effect of anti motility drugs
1. Megacolon and perforation in acute ulcerative colitis
Should be avoided in infectious diarrhoea
67
Name a bile acid
Ursodeoxycholic acid
68
When are bile acids given
Primary biliary cirrhosis
69
Effect of bile acids
Reduces jaundice, ascites and itching by slowing down liver biochemistry
70
Mechanisms of bile acid
ursodeoxycholic acid reduces cholesterol absorption and is used to dissolve cholesterol gallstones
2. Helps regulate cholesterol by reducing rate at which intestines absorb cholesterol molecules while breaking up micelles containing cholesterol
71
Why is surgery still preferred to ursodeoxycholic acid
Cause gallstones can recur
72
Adverse effect of ursodeoxycholic acid
1. Nausea
2. Diarrhoea
3. Gallstone calcification
73
Where is ursodeoxycholic acid contraindicated
1. Gallbladder impairment
2. Calcium gallstones
3. Severe liver impairment
