Immunisation and d/o of immunity

Question 1

Difference between passive and active immunity

Answer 1

Passive immunity is immunity transfered from another being to a person. This results only in temporary immunity

Active immunity is made by the person’s own immune system - usually permanent

Question 2

Examples of ways to transfer passive immunity?

Answer 2

Breast milk transfer IgA, placental transfer of IgG,

Question 3

Live attenuated vaccines require at least 3 doses to confer life long immunity - true or false?

Answer 3

False, live attenuated usually only require 1 dose.

Question 4

MMR vaccine is an inactivated vaccine - true or false?

Answer 4

False, MMR vaccine is a live attenuated vaccine

Question 5

Why are polysaacharide based inactivated vaccines not very effective on children?

Answer 5

Require T-independent activation of B cells which is not yet mature in young children.

Question 6

It is ok to give inactivated vaccines to pregnant women - T or F?

Answer 6

T. Do not give live attenuated vaccines.

Question 7

What must be recorded when giving a vaccine?

Answer 7

Expiry date, batch number

Question 8

What is MHC restriction?

Answer 8

When a T cell is not able to be activated by an APC because the MHC subtype is different.

Question 9

Explain graft VS host disease, what type of transplant is it common in

Answer 9

When immune cells from the donor cells treated the recipient tissue as foreign and attack it. Bone marrow transplant.

Question 10

What 3 factors lead to graft v host disease?

Answer 10

Graft has to contain immunologically competent cells

Host has immunogenic alloantigens which are lacking in the donor graft

Host is incapable of mounting an effective immunologic reaction against the graft.

Question 11

How to treat graft v host disease rejection?

Answer 11

Plasmapheresis to get rid of B cells/antibodies, then wipe out T cell population.

Question 12

Describe direct allorecognition in rejection

Answer 12

When donor APC presents donor tissue to recipient lymphocytes, activating recipient T cells to attack donor organ = acute rejection

Question 13

Difference between direct allorecognition and indirect allorecognition in rejection

Answer 13

In indirect allorecognition, donor tissue is presented by host APC to host lymphocytes, activating host immune system to fight donor tissue. = chronic rejection

Slow, less acute

Question 14

Describe hyperacute rejection

Answer 14

When recipient body also contains preexisting antibodies against the tissue/antigen,

Question 15

What happens in chronic rejection?

Answer 15

Concentric arterosclerosis of graft blood vessles

Infiltrative fibrosis, results in ischaemia

Question 16

Difference between corneal, solid organ and bone marrow transplants

Answer 16

Corneas are immune privileged, no rejection

Solid organ have to be ABO matched, HLA is not crucial but will be better if it is - requires long term immunosuppresion

Bone marrow transplant is crucial in requiring HLA matching. If from parents, can do half HLA matching, then wipe out subsequent T cells in recipient. Does not require long term immunsuppresion.

Question 17

B cell deficient infants will show low antibodies, normal PMCs and T cells - true or false?

Answer 17

True

Question 18

B cell deficient baby will present within 1 month of birth - true or false?

Answer 18

False, maternal IgG can protect a baby until about 5 months

Question 19

What will a complement deficient baby present with

Answer 19

Recurring infection, joint problems, glomerulonephritis.

Due to inability to clear immune complexes.

Question 20

What cells are deficient in neutropenia?

Answer 20

Phagocytes

Question 21

What pathogens are common in phagocytic defects?

Answer 21

Staph, pseudonomnas

Candida, aspergillus

Question 22

What is the common presentation for patient with B cell deficiency?

Answer 22

Recurrent otitis media and pneumonia >5 months

Question 23

What can cause secondary B cell deficiency

Answer 23

Chemotherapeutic drugs
Plasmapheresis
Nephrotic syndrome

Question 24

What can cause secondary phagocyte deficiency?

Answer 24

Chemotherapy/radiotherapy

Antibiotics

Question 25

What drug can cause complement deficiency?

Answer 25

Eculizumab - C5 inhibitor

Cause recurrent meningococcal infections

Question 26

What protozoan infection is common in antibody deficiency?

Answer 26

Giardia

Question 27

What viral infections are common in primary antibody deficiency?

Answer 27

Enterovirus

Echovirus

Question 28

What bacterial infections are common in primary antibody deficiency?

Answer 28

S aureus
S pneuomoniae
H influenzae

Question 29

What is the most common inherited antibody deficiency?

Answer 29

X-linked autosomal (XLA) recessive agammaglobulinaemia.

Question 30

How does X-linked autosomal (XLA) recessive agammaglobulinaemia present?

Answer 30

From 6-12 months age
Invasive bacterial infection, of pulmonary/ENT region
Gastroenteritis, pyoderma and some meningitis.

Question 31

What causes chronic granulomatous disease?

Answer 31

Inherited defect of gene used in producing reactive oxygen species - i.e. Phagocytes cannot neutralise engulf pathogens.

Question 32

How does a patient with chronic granulomatous disease present?

Answer 32

Staph aureus from 2 years, atypical mycobacterial and parietal fungal abscess

Also suppurative lymphadenitis, liver abscess, pulmonary infiltrates, burkholderii septicaemia.

Question 33

How does a SCID baby present?

Answer 33

Between 6-10 weeks with persistent viral gut and lung infection (PCP)

Question 34

What are the pathogens common in SCID babies

Answer 34

Candida, aspergillus, cryptococcus
PCP, toxopasma, cryptosporida
RSV, rotavirus, norovirus, CMV, adenovirus