DiarrhoeaA thrilling topic for a Wednesday morning!

Emma Lowe

Overview

• Assessment• Causes• Management– Non-specific– Specific

Question

A 52 year old man presents with a 6 month history of epigastric pain and diarrhoea. Passes up to 5 watery stools per day which are sometimes difficult to flush and foul smelling. He can recall one episode of black stool in the past month. Which would be the best investigation to aid diagnosis?

A – CCK testB – Parathyroid Sestamibi ScanC – Secretin stimulation testD – Fasting VIP plasma levelE – OGD

Types of diarrhoea

• Increase in frequency and fluidity of bowel action

• Osmotic – Increased amounts of water are drawn into the bowel

• Secretory – Enhanced formation of gastrointestinal secretions

• Often multi-factorial

Assessment

• History– Steatorrhoea– Blood/mucus– Recent constipation– Profuse watery diarrhoea not relieved by fasting

(hormonal)• Review medication and diet• Look for signs of dehydration• Stool sample

Causes• TOP THREE (in cancer patients)– Laxative overuse– Overflow diarrhoea– Partial bowel obstruction

• Drugs• Treatment associated• Tumour related• Malabsorption syndromes• Gastroenteritis• Hormone related• Pseudomembranous colitis

Foods

• Raw fruit (fresh and dried)• Nuts• Greens• Beans• Lentils• Onion• Coleslaw• Sauerkraut• Spicy foods• Wholegrain• Wholemeal

Management

• Consideration of the underlying cause• Specific vs non-specific antidiarrheal agents• Increase fluid intake• Treat the physiological effects• Protect the perianal skin – Zinc cream

Loperamide

• Potent µ opioid receptor agonist• Directly absorbed in the gut wall and increased GI transit

time by decreasing propulsion and non-propulsive activity• Increases anal sphincter tone and can improve night-time

continence• Doesn’t cross blood brain barrier so no central effect• Maximum effect may take 16-24 hours and last 3 days• 4mg PO STAT, 2mg post BO (max 16mg/24hrs)• Can increase up to 24mg/24hrs in treatment related• Chronic diarrhoea aim for 2mg BD

Other non-specific drugs

• Aim to use a single drug• Codeine/Morphine– Associated with central effects

• Diphenoxylate (with atropine = Lomotil)– 2.5mg QDS (equivalent to Loperamide 2mg BD)– Opioid agonist, similar to loperamide– Does cross the blood brain barrier so can have

central effects

Common causes

• Laxative induced diarrhoea– Should resolve within 24 hours of laxatives being

stopped. – May need to introduce at a lower dose.

• Overflow diarrhoea– Rectal measures and laxatives

• Bowel obstruction– Surgery– Symptomatic management (Octreotide, steroids,

buscopan)

Drugs• Laxatives• Antacids• Magnesium salts• SSRIs• Antibiotics• Iron• Mefanamic acid• NSAIDs• Stop drug +/- switch to an alternative

• Oestrogens• Theophyllin• Anticholinergics• Sulphonylureas• Caffeine• Chemotherapy – 5-FU,

Mitomycin, Methotrexate, Doxorubicin, Etoposide

Radiation induced diarrhoea• Common in 2nd-3rd week of radiotherapy to pelvis/abdomen• Risk factors: high dose and length of treatment, volume of normal bowel

treated, tumour size, concomitant chemotherapy, • NCI grading

- 0: None- 1: Increase of <4 stools over pre-treatment- 2: Increase of 4-6 stools or nocturnal stools- 3: Increase of 7+ stools or incontinence or need for parenteral hydration- 4: Physiological consequences requiring intensive care or haemodynamic collapse

• 5-15% will go on to develop chronic diarrhoea• Mild to moderate (1-2) – Loperamide (up to 24mg/24hrs then switch to

Octreotide)• Severe (3-4) – Octreotide via CSCi• Aspirin/NSAIDs inhibit prostaglandins which reduce gastric secretions (RCTs

show mixed results)• Various other possibilities including steroids, formalin, oestrogen/progesterone,

cholestyramine • Cochrane review protocol has been set but not done

Malabsorption

• Carcinoma of head of pancreas causing pancreatic insufficiency (steatorrhoea)

• Gastrectomy: poor mixing of fluid with pancreatic secretions (steatorrhoea)

• Vagotomy: Increased water secretion into the colon• Ileal resection: less able to absorb bile acids. Fluid in

bowel increased. • Colectomy: Water-absorbing properties are lost. May

need extra fluid and salt.• Fistula: Any or all of these problems

Malabsorption

• Fat Malabsorption– Steatorrhoea– Pancreatic insufficiency, biliary obstruction, bacterial

overgrowth– Pancreatic enzymes, H2 receptor antagonists/PPI (to

prevent breakdown of pancreatic enzymes), dietary advice

• Bile salt malabsorption– Ileal resection, bacterial overgrowth– Cholestyramine: bile salt chelator

Pseudomembranous colitis

• Acute, exudative colitis usually caused by C.Diff.• Copious diarrhoea with mucus and blood, abdominal

cramps, fever.• Any antibiotics, most typically Ciprofloxacin and

Cephalosporins.• PPIs increase the risk, as does immunocompromise• Stool for C.Diff toxin• Sigmoidoscopy• Avoid antidiarrheals• Metronidazole 400mg TDS for 14 days• Vancomycin 125mg QDS for 14 days

Hormonal

• Carcinoid– Diarrhoea in 75%– 5HT3 antagonists can reduce the diarrhoea– Octreotide

• Zollinger-Ellison syndrome– Gastrin secreting tumour, causes increased gastric acid production. – Main symptoms related to acid production– Fasting Gastrin (>1000) +/- secretin stimulation test– PPI, H2 Antagonist for symptoms, definitive surgery– Octreotide

• Others– Medullary carcinoma of the thyroid– VIPoma

Others

• Local tumours – Surgery, chemotherapy, radiotherapy (palliative for symptomatic benefit)

• Bacterial overgrowth – Broad spectrum antibiotics

Question

A 52 year old man presents with a 6 month history of epigastric pain and diarrhoea. Passes up to 5 watery stools per day which are sometimes difficult to flush and foul smelling. He can recall one episode of black stool in the past month. Which would be the best investigation to aid diagnosis?

A – Short Synacthen testB – Parathyroid Sestamibi ScanC – Secretin stimulation testD – Fasting VIP plasma levelE – OGD

Question - AnswerA 52 year old man presents with a 6 month history of epigastric pain and diarrhoea. Passes up to 5 watery stools per day which are sometimes difficult to flush and foul smelling. He can recall one episode of black stool in the past month. Which would be the best investigation to aid diagnosis?

A – Short Synacthen testB – Parathyroid Sestamibi ScanC – Secretin stimulation testD – Fasting VIP plasma levelE – OGD

Zollinger Ellison Syndrome

References

• Fallon, M. O’Neill, B. ABC of palliative care: Constipation and diarrhoea. BMJ, 1997;315:1293

• PCF4• Watson et al (Eds). Oxford Handbook of

Palliative Care. 2009, 2nd Edition, Oxford University Press

• Woodruff, R (Ed). Palliative Medicine. 2004, 4th Edition, Oxford University Press