Introduction To Infection

Question 1

What are the 5 signs of inflammation?

Answer 1

Tumour (Swelling) 
Calor (Heat) 
Rubor (Redness) 
Dolor (Pain) 
Loss of function

Question 2

How does gram positive bacteria show when stained with violet dye?

Answer 2

Purple

Question 3

What colour does gram negative bacteria stain with violet dye?

Answer 3

Pink/red

Question 4

Bacteria reproduce by which process?

Answer 4

Binary fission

Question 5

During log phase of bacterial reproduction, what happens to the number of bacteria?

Answer 5

Increases exponentially with time

Question 6

What happens during the “stationary phase” of bacterial replication? Why?

Answer 6

Growth slows and ceases

Due to nutrients being depleted and toxic waste products accumulating

Question 7

Put these in order of size, smallest to biggest:

Eukaryotic cells, Prions, Bacteria Proteins, Viruses, Worms

Answer 7

Prions (smallest), Proteins, Viruses, Bacteria, Eukaryotic cells, Worms (largest)

Question 8

What type of microscope is required to see viruses?

Answer 8

Electron microscope

Question 9

Bacteria always have what type of genetic material?

Answer 9

Double stranded DNA

Question 10

What are the three shapes that bacteria can take?

Answer 10

1. Bacillus (rod)
2. Coccus (sphere)
3. Spirillus (spiral)

Question 11

Cocci can take which two forms?

Answer 11

Clusters or chains

Question 12

Name 5 types of bacterial virulence factor

Answer 12

• Host entry mechanisms e.g. LPS
• Adherence to host cells e.g. Pili and fimbriae
• Invasiveness e.g. Enzymes (collagenase)
• Iron sequestration e.g. Siderophores
• Toxins

Question 13

How can bacterial toxins be divided into two groups?

What is this division based upon?

Answer 13

Exotoxins- deliberate release

Endotoxins- result of bacterial cell death when it breaks down (LPS)

Question 14

Fungi can be divided into which two catergories?

Answer 14

Yeasts (single celled)

Moulds (multicellular)

Question 15

Parasites can be divided into which two broad categories?

Answer 15

Protozoa (single celled)

Helmiths (multicellular)

Question 16

Name as many mechanisms of infection as you can

Answer 16

Contiguous spread 
Inoculation 
Haematogenous 
Ingestion 
Inhalation
Vector 
Vertical transmission

Question 17

Name factors relating to the patient that contribute to the infection model of pathogens

Answer 17

The person: age, gender, physiological state, pathological state, social/behavioural factors
The time: calendar time, relative time
The place: current, recurrent

Question 18

Outline some of the managements that are present in the infection model

Answer 18

Diagnosis: History, Examination, Investigation
Treatment:
Supportive- symptom relief, physiological restoration
Specific- antimicrobials, surgery, drainage, dead space removal
Infection prevention: hospital and community