4. GI Infections Flashcards
What are the roles of bacteria in normal GI? (5 things)
- Synthesise and excrete vitamins (vit K, B12, Thiamine)
- Prevent colonisation by pathogens
- Kill non-indigenous bacteria
- Stim GALT dev (Gut assoc lymphoid tissue - works in immune system)
- Stim prod of natural antibodies
What are the categories of bacteria in the GI tract?
- Cocci / bacilli
- Gram +ve / gram -ve
- Aerobic / anaerobic
What are the different types of aerobic / anaerobic bacteria?
- Obligate aerobes = NEED oxygen
- Obligate anaerobes = DIE @ oxygen
- Facultative anaerobes = Prefer oxygen but can live without it
What type of bacteria does the mouth have?
Anaerobic
What bacteria does the nose have?
Staphylococcus and Streptococcus
What are the causes of GI infections? (5 things)
- Gastroenteritis (food poisoning)
- Cholera
- Intestinal Parasites
- Bacteraemia
- Septicaemia
What are the causes of Gastroenteritis?
Food / drink contaminated with toxins
What are the symptoms of Gastroenteritis?
Vomiting and diarrhoea
What organism causes Gastroenteritis?
Samonella
What toxin causes Gastroenteritis?
Staphyolococcus
What organism causes Cholera and how?
Vibrio cholerae
Affects ileum –> moves water and salt into lumen –> diarrhoea –> dehydration
What is the management for Cholera?
Replace lost water and electrolytes
What are examples of intestinal parasites and what they cause? (2 things)
Protozoans –> Gastroenteritis
Helminth infestations –> malabsorption
How is bacteraemia managed in the body?
Bac cleared from blood stream by liver / spleen / MAC
What is the difference between bacteraemia and septicaemia?
Bacteraemia = PRESENCE of bac in blood Septicaemia = MULTIPLICATION of bac in blood
What is the difference between food poisoning and food intoxication?
Food poisoning = general illness resulting from consumption of food
Food intoxication = ingestion of TOXINS contained within food
What is the cause of Travellers Diarrhoea?
Enterotoxigenic E. Coli (ETEC)
What is the diarrhoea like in Travellers Diarrhoea?
Severe cholera-like (beh watery)
Is there inflammation in Travellers Diarrhoea?
No
What is the cure for Travellers Diarrhoea?
It is a self-limited condition
Resolves on its own and has no long-term harmful effect
What are the causes of Inflamm Bowel Disease? (4 things)
- Crohn’s Disease
- Ulcerative Colitis
- Diversion Colitis
- Diverticular Colitis
What are the causes of intestinal infection?
Pathogens / toxins
