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Infection (Milly's) > Introduction To Infection > Flashcards

Flashcards in Introduction To Infection Deck (12)
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1
Q

What is an infection?

A
Invasion of a host's tissue by microorganism 
AND
Disease caused by:
-microbial multiplication
-toxins
-host response
2
Q

What are the different ways in which someone can get infected? And give examples (4)

A
  • From their own microbiota (UTI)
  • physical contact, person to person (pneumonia)
  • vectors, animals (malaria, swine flu)
  • environment (water, food, air, surfaces)
3
Q

What are the 2 types of transmission and give some examples

A
Horizontal
-contact 
-inhalation
-ingestion (faecal-oral route)
Vertical
-mother to child
-before or at birth
4
Q

What are the two ways in which someone can inhale a pathogen?

A

Droplet

Aerosols

5
Q

What are the symptoms of infection? (5)

A
Rubor (redness)
Calor (heat)
Dolor (pain)
Tumor (swelling) 
Functio laesa (loss/disturbance of function)
6
Q

How do microroganisms cause disease?

A

Virulence factors; endo and exotoxins (cytolytic, AB toxins, superantigens, enzymes)
Host cellular damage; direct and consequent to host immune response

7
Q

How do we know if someone has an infection?

A

History -symptoms and potential exposures
Examination- organ dysfunction
Investigations- specific and supportive

8
Q

What are some examples of supportive investigations which help us know if someone have an infection?

A
  • full blood count- neutrophils and lymphocytes
  • CRP
  • blood chemistry- liver and kidney function tests (UandEs)
  • imaging-x-ray, ultrasound, mri
  • Histopathology

**can repeat these tests throughout the management of the patient to check for improvement and worsening of symptoms

9
Q

What are some examples of bacteriological investigations that can be done to help determine whether someone has an infection?

A
  • specimen types- swabs, fluids and tissues
  • culture anything!!! - gram stains
  • antigen detection
  • nucleic acid detection
10
Q

How can we detect viruses?

A
Antigen detection (finding virus) - ELISA 
Antibody detection (patients repsonse)
Detecting viral nucleic acid (DNA/RNA)
11
Q

Give examples of disease determinants?

A

Pathogen: virulence factors, inoculum size, antimicrobial resistance

Patient; site of infection and co-morbidities (if you’re elderly/young/ diabetic etc)

12
Q

How would you prove that a disease is due to a microorganism?

A

1) the microorganism mist be found in abundance in all organisms suffering with the disease but should not be found in healthy organisms
2) the microorganisms must be isolated form a diseased organism and grown in pure culture
3) the cultured microorganism should cause disease when introduced into a healthy organism
4) the microorganism must be re-isolated from the inoculated diseased experimental host and identified as being identical to the original specific causative agent