Gut pathogens Flashcards
1
Q
Candida
A
- Intestinal yeast
- C. albicans is the most recognised in humans pathogens
- Linked to IBS, fatigue, + itchy skin, recurrent thrush
- Can be managed by nystatin, but not commonly used due to side-effects
2
Q
Types of Bacterial pathogens
A
- Invasive ie EPEC, Shigella, Campylobacter, Salmonellae
- Cytotoxic ie EPEC, EHEC, some Shigella
- Toxigenic ie V. Cholerae, ETEC, some Shigella
- Adhesive ie EAEC
3
Q
Helicobacter pylori
A
- Common gastric pathogen
- 6-8 Polar flagellas
- Invades mucosal layer
- Associated with Type B gastritis, peptic ulcer, gastric carcinoma
- Possible faecal oral spread, but still not fully confirmed
- Antimicrobials used to treat it
4
Q
Bacteroides
A
- Gram -ve rods
- The dominant genus in the colon
- New research shows that there is association with obesity
- Proteolytic + sacchorolytic
- One type is known to be involved in cross-talk, communicating to human cells to influence diet + nutrient intake
5
Q
Clostridia
A
- Gram +ve spore formers
- Anaerobic
- Some produce toxins
- Proteolytic
- Normal resident of human flora
- Overgrowth can be problematic
- c. difficile
+ Occurs in association with antibiotic exposure
+ PMC
+ Formas plaques composed of mucin, fibrin, + gut cells
+ Most frequently implicated antibiotics: Ampicillin, clindamycin, cephalsporins
+ 2 types of toxins are produces
+ Vancomycin + anion resins used as treatment
6
Q
Fusobacteria
A
- Filamentous
- Anaerobic
- Gram +ve
- Its role in the gut is unclear, but contributes to several diseases, including periodontal (gum) problems + tropical skin ulcers
7
Q
Staphylococci
A
- Gram +ve
- Most are completely harmless, but can cause diseases in some
- Contains MRSA variant
8
Q
Streptococci
A
- Gram +ve coci
- Some used as probiotics
- Certain species are haemolytic
- Grows in chains or pairs
- Found in mouth, skin, intestine + URT of humans
9
Q
Enterococci
A
- Gram +ve, often occur in pairs
- High level of endemic antibiotic resistance
- Previously used as probiotics
- Facultatively anaerobic
10
Q
Vellonella
A
- Gram -ve cocci
- Non-motile diplococci
- Occurs in mouth + gut
- Parasitic in nature
11
Q
E. coli
A
- Gram -ve rods
- Some are pathogenic + cause severe gastroenteritis
- Probiotic variants exist
- Used as indicators in poo
12
Q
Mycobacterium
A
- Implicated in Crohn’s disease
- Peak occurance in 15-35 years old
- Involves a granulomatous reaction
- Varies in the level of inflammatory response
- Fever, pain, triredness, diarrhoea
13
Q
Sulphate-reducing bacteria
A
- Occur in 45% of healthy persons
- Reduce sulphate to sulphide in conjunction with an e- donating substrate
- Competes with methangoens for H2
- Commonest genus: Desulfovibrio
- Pathological role in the gut remains unclear