Microbiology Flashcards
Which bacterial factors increase bacterial success rate?
High growth rate, dispersal capability, phenotype plasticity, genetic diversity
Define colonization.
Establishment of a microorganism in a host
Describe how MALDI-TOF differentiates pathogens.
Compares protein content of the cell wall to a database.
Which GI pathogens is MALDI-TOF not good for?
E. coli, salmonella
Which agars can be used to grow enterobacteria?
Blood, MacConkey, CLED, chromogenic
C. diff has two different toxins. Name them.
A -> enterotoxin, B -> cytotoxin
How does C. diff infect patients?
Antibiotics that kill off natural bacteria, allowing overgrowth. Transmissable by spores
How does a C. diff infection present?
Diarrhoea, abdo pain, pseudomembranous colitis
Which antibiotics are used to treat C. diff?
Less severe -> metronidazole, severe -> vancomycin
Describe rotavirus.
Most common D&V cause in children < 3.
Diarrhoea with no blood, dehydration.
Rehydration is key, diagnosed with PCR
Vaccine given at 2 & 3 months
Describe norovirus.
Affects all ages, explosive D&V
Rehydration is key
PCR from faeces and vomit
When are patients most infectious?
With diarrhoea
Define diarrhoea.
> 3 unformed stools in 24 hrs
What is dysentry? Give the main symptoms.
Inflammation of the intestine. Diarrhoea with blood/mucus, fever, abdo pain, tenesmus
Excluding E. coli, what are the six main bacteria from food?
Bacillus cereus, staph aureus, scombroid, campylobacter, salmonella, listeria
What are the three main tests for bacteria from food?
Molecular testing, stool sample, PCR
What does Shigella cause? What are the four types?
Dysentry, A/dysenteriae, B/flexneri, C/boydii, D/sonnei
Describe the pathology of Shigella.
Shiga toxin binds to renal cells/RBCs/others to inhibit protein synthesis.
Name the four main types of E. coli.
Enterotoxigenic, enteropathogenic, enteroinvasive, enteroaggregative
What are the main symptoms of E. coli infection?
Abdo pain, fever, pallor, bloody diarrhoea
Name the three main fevers suspected in travellers.
Acute travellers diarrhoea, enteric fever, amoebiasis
What are the symptoms of giardiasis in travellers?
Watery diarrhoea, bloating, flatulence, abdo cramps, weight loss
How are helminth infections diagnosed? What are the two main types?
Eosinophillia, eggs in faeces
Schistosomiasis/Chagas disease
