CA - Diarrhoea (patho not tested PNP tested)

Question 1

What are the causes of diarrhoea?

Answer 1

1. Infectious
   - caused by pathogenic micro-organisms
   - bacteria: salmonella, shigella, ecoli, c-diff
   - viruses: adenovirus, norovirus
2. Non-infectious
   - side effect of meds - disrupts intestinal flora (abx)
   - food intolerance
   - underlying conditions

Question 2

What are the different types of diarrhea?

Answer 2

1. Inflammatory
   - Inflammation -> digestion to intestinal mucosa
   - can be caused by Crohn disease, food poisoning
2. Fatty
   - impaired digestion & absorption of fats -> fat excreted in stools -> loose, oily, pale stools
3. Watery - water abnormally secreted into stools instead of being absorbed by intestines

A. Osmotic
- osmotic imbalance in GI tract
- usually seen in ppl with lactose intolerance -> lactose cant be digested & remains osmotically active -> attracts water molecules -> decreased absorption -> diarrhoea

B. Secretory
- Infectious micro organisms secrete toxins that disrupt normal fxn of intestinal cells -> trigger excess fluid & electrolyte secretion
- Laxatives, meds & conditions like diabetic neuropathy can also cause

Question 3

What are the complications of diarrhoea?

Answer 3

1. Dehydration
   - poor skin tugor & dry mucous membranes
   - severe: sunken eyes + delayed capillary refill -> electrolyte imbalance + metabolic alkalosis = LIFE-THREATENING
2. Malnutrition
3. GI perforation
4. Sepsis
5. Death

Question 4

How do you diagnose diarrhoea?

Answer 4

Stool tests -> If viral, parasitic, or inflammatory diarrhoea is suspected (PCR, antigen, microscopy)
Stool culture -> If bacterial diarrhoea is suspected (e.g., fever, bloody stools, prolonged diarrhoea)

Question 5

Treatment of diarrhoea?

Answer 5

1. Oral rehydration
2. Low fibre diet - easier to digest -> more time for absorption of fluids & nutrients + less stimulation of intestines

Might need
3. Anti-diarrheal meds
4. Antimicrobials for infectious D
5. Probiotics to restore intestinal flora
6. Fecal microbiota transplant for recurrent episodes of C-diff - introduce healthy bacteria from a donor -> outcompete C-diff bacteria & effectively eliminate it

Question 6

What is the electrolyte imbalance seen in patients with chronic diarrhea?

Answer 6

Hypokalemia

Question 7

A 30-year-old man hates milk and says, “I get constipated, so I use laxatives.” He picked up food from a take-out restaurant that was selling fried rice, which he consumed later. His father has Crohn’s disease. He presents with nausea, vomiting, and voluminous diarrhea with no change in osmolar gap. What is the probable cause of diarrhea?

Answer 7

Food poisoning

Question 8

How does decreased motility lead to diarrhoea?

Answer 8

Cause bacteria overgrowth and lead to diarrhea