Infection

Question 0

What is the difference between red pulp and white pulp?

Answer 0

Red- RBCs breakdown + iron recycling

White- B + T lymphocytes

Question 1

What is lymphadenopathy?

Answer 1

Swollen or enlarged lymph nodes, often due to infection

Question 2

Gram Staining- outline the process

Answer 2

Crystal Violet
Iodine
Alcohol wash
Red Stain

Question 3

Gram positive stains what colour?

Answer 3

Purple

Question 4

Gram neg- what colour?

Answer 4

Red

Question 5

Where is CRP produced?

Answer 5

Liver

Question 6

Name the pathogen that causes malaria and what type of pathogen it is

Answer 6

Plasmodium falciparum or plasmodium vivax

Protozoan Parasite

Question 7

What is the ABC for travelling to places with high risk of malaria?

Answer 7

Assess risk, Bite prevention, Chemoprophylaxis

Question 8

What is the vector for malaria?

Answer 8

Female Anopheles Mosquito

Question 9

Typhoid and paratyphoid fever are also know as what?

Answer 9

Enteric fever

Question 10

What is the difference in symptoms for typhoid and paratyphoid fever?

Answer 10

Same symptoms (abd discomfort, constipation, dry cough, hepatosplenomegaly) Symptoms generally milder for paratyphoid.

Question 11

Who would need a typhoid vaccine?

Answer 11

Lab personnel likely to come into contact with it

People traveling to high risk areas (Asia, Africa, Sth America)

Question 12

What type of microbes do MHCI molecules deal with?

Answer 12

Intracellular (often viruses)

Question 13

What is the difference between Protozoa and Helminths?

Answer 13

Protozoa are single cellular and Helminths are multicellular eg worms

Question 14

What size (in m) are viruses?

Answer 14

10^-8 to 10^-7 m

Question 15

Mechanism of infection covers 7 possible transmission routes, name them and give examples (name VIVI ones)

Answer 15

Vector- lime’s disease, malaria, Sth American trypanomyosis
Inoculation- fungal eye infection
Vertical Transmission- syphilis (mother to child) Hep B (during birth)
Inhalation- aerosol or droplets -TB, chickenpox, winter VD

Question 16

Mechanism of Infection, name and give examples of routes of transmission for pathogens (CHIng)

Answer 16

Contiguous or direct spread- UTI, peritonitis (from appendicitis)
Haematogenous- pathogen moves through blood (eg ulcers in gums allowing Viridans Streps to move to cause endocarditis)
Ingestion- food poisoning, cholera

Question 17

What is debridement?

Answer 17

A specific treatment involving removal of infected tissue (eg bone) from the body to clear the pathogen.

Question 18

What role does LPS (on the cell wall) have in N meningitidis?

Answer 18

Acts as an endotoxin and triggers inflammation

Question 19

Strep pneumoniae- gram stain?

Answer 19

Gram +ve

Question 20

What are the benefits of having normal flora?

Answer 20

They compete with pathogens for resources and attachment sites
Some produce antimicrobials
Some synthesise vitamins (eg K and B12)

Question 21

What are the sepsis 6?

Answer 21

1) High flow O2 2) Blood cultures 3) empiric IV antibiotics 4) serum lactate levels 5) IV fluid resuscitation 6) accurate urine output

Question 22

What is SIRS?

Answer 22

Systemic Inflammatory Response Syndrome
Two or more of
Low or high temp (usual range 36-38)
High HR (>90)
High RR (>20)
Low or high WBC (12x10^9)

Question 23

What is severe sepsis?

Answer 23

SIRS + organ dysfunction/hypo perfusion

Question 24

Define septic shock

Answer 24

Significant drop in blood pressure despite IV fluids as well as Severe sepsis

Question 25

Name 5 potential complications of sepsis

Answer 25

Irreversible hypotension
Respiratory failure
Acute kidney injury leading to renal failure
Raised intracranial pressure
Ischaemic necrosis affecting digits/hands/feet

Question 26

Name potential bacterial causes of cellulitis

Answer 26

Strep pyogenes

Staph aureus

Question 27

Which haemolytic streptococci only partially break down RBCs?

Answer 27

Alpha haemolytic = partial haemolytic

Question 28

Give two examples of alpha haemolytic strep

Answer 28

Strep pneumoniae (pneumococcus)
Viridans streptococcus

Question 29

What are beta-haemolytic strep and what are the different subtypes?

Answer 29

Completely break down RBCs. The groups active as pathogens in humans are Group A and Group B. Groups C & G also contain some pathogens affecting humans (pharyngitis and cellulitis).

Question 30

What are three examples of horizontal gene transfer?

Answer 30

Conjugation (bacteria to bacteria)
Transduction (bacteriophage)
Transformation (free DNA)

Question 31

What are Group B strep responsible for?

Answer 31

Neonatal infections

Question 32

Give examples of gram positive bacilli

Answer 32

Clostridium (perfringens and difficile)

Listeria monocytogenes

Question 33

Give examples of gram negative bacilli

Answer 33

E. coli, Klebsiella pneumoniae, Salmonella typhi, Legionella, Helicobacter, Haemophilus influenzae, bacterioides spp.

Question 34

Give two diseases caused by mycobacterium

Answer 34

TB

Leprosy

Question 35

Which immunoglobin triggers mast cell degranulation in a type I hypersensitivity reaction?

Answer 35

IgE

Question 36

Give 3 examples of beta lactams

Answer 36

Penicillins eg amoxicillin
Cephalosporins eg Ceftriaxone
Carbapenems eg meropenem

Question 37

Give 2 families of antibacterials that target the cell wall

Answer 37

Beta lactams and Glycopeptides

Question 38

Give 3 families of antibacterial that target protein synthesis

Answer 38

Tetracyclines, aminoglycosides and macrolides

Question 39

Give an example of a macrolide, what does it target?

Answer 39

Erythromycin, Protein Synthesis

Question 40

Give an example of an aminoglycoside

Answer 40

Gentamycin