Diarrhoea Flashcards
What is diarrhoea?
•From a clinical perspective, diarrhoea can be defined as the passage of:
Three or more loose or liquid stools per 24 hours, and/or
Stools that are more frequent than what is normal for the individual lasting <14 days, and/or
Stool weight greater than 200 g/day.
How is diarrhoea classified based on duration?
•Based on duration, diarrhoea is classified as:
Acute (≤14 days)
Persistent (>14 days), or
Chronic (>4 weeks).
Pathophysiology of diarrhoea
Diarrhoea occurs when various factors interfere with the normal process of digestion, resulting in decreased absorption or increased secretion of fluid and electrolytes, or increase in bowel motility.
What are the two types of diarrhoea based on cause?
Infectious diarrhoea
Non-infectious diarrhoea
How is infectious diarrhoea acquired?
Most are acquired through the faecal-oral route, from contaminated water or food. Most infections are self-limiting or treated easily.
When are specific investigations warranted when a patient is diagnosed with infectious diarrhoea?
Specific investigations are warranted when resources are available in moderate to severe disease, or if there is a public health risk such as high risk for spreading disease to others.
What are the bacterial infections that can cause infectious diarrhoea?
E.coli Campylobacter Salmonella Shigella C. difficile S. aureus
How is E.coli acquired?
(beef, pork, apple cider, milk, cheese and spinach)- common cause of traveller’s diarrhoea.
How is campylobacter acquired?
- infection is generally acquired from undercooked contaminated poultry in developed countries.
Clinical features of infectious diarrhoea when it is caused by campylobacter
Diarrhoea can be watery or bloody and is frequently associated with crampy abdominal pain.
What are the serious complications of infection with campylobacter?
It has been linked to serious complications such as reactive arthritis and Guillain-Barre syndrome.
How is salmonella acquired?
Poultry and eggs
How is shingles acquired?
Common in day care centres. Presents with bloody stools, fever, abdominal cramps, and tenesmus.
How is c.dif acquired?
This is one of the most common hospital-acquired (nosocomial) infections and is a frequent cause of morbidity and mortality among older hospitalised patients. C difficile colonises the human intestinal tract and after the normal microbiota has been altered by antibiotic therapy it can lead to pseudomembranous colitis. Recurrent disease is common and thought to be due to altered host immunity. C difficile produces toxins, which are implicated in the disease.
How is s.aureus acquired?
Leads to vomiting, and in some instances diarrhoea, within 4 to 8 hours following the ingestion of food contaminated with pre-formed toxin.
Which viral infections cause diarrhoea?
Rotavirus
Norovirus
Clinical features of rotavirus
The leading cause of viral gastroenteritis and diarrhoeal deaths worldwide. It is a vaccine-preventable disease. It causes diarrhoea that results in volume depletion in children and young adults. This infection peaks during cooler weather.
Clinical features of norovirus
this is a major cause in epidemic viral gastroenteritis. Noroviruses are the most common cause of outbreaks of non-bacterial gastroenteritis in the US.