Immunology- Immunodeficiency

Question 1

Which type of immune response is immediate?

Answer 1

Innate

->adaptive is slower as allows time for cell movement and interaction between cell types

Question 2

Which type of immune response has memory of previous responses?

Answer 2

Adaptive

->innate immune response has no memory

Question 3

List some of the cellular components in innate immunity.

Answer 3

Dendritic cells
Neutrophils
Macrophages
NK cells
B1 cells
Mast cells

Question 4

List some of the cellular components in adaptive immunity.

Answer 4

Lymphocytes- T, B

Question 5

What is the role of a phagocyte?

Answer 5

Engulfs and destroys microbes

Question 6

What are the roles of B cells?

Answer 6

Differentiates into plasma cells producing antibodies

Complement activation

Toxin neutralization

Opsonization

Question 7

What are the roles of helper T cells?

Answer 7

Help B cell by providing signals necessary for antibody production

Question 8

What is the role of Cytotoxic T cells?

Answer 8

Destroy virally infected cells and tumour cells

Question 9

What is the role of T regulatory cells?

Answer 9

Supress auto-reactive T cells

Question 10

What is the role of a NK cell?

Answer 10

Destroys virally infected cells and tumour cells

Question 11

What is Opsonization?

Answer 11

Process that helps your immune system identify and destroy old pathogens

Question 12

What are the roles of complement?

Answer 12

Opsonization
Terminal components create the membrane attack complex

Question 13

Which antibody responds first in infection?

Answer 13

IgM

Question 14

What is the difference between primary and secondary immunodeficiency?

Answer 14

Primary- something wrong with the actual immune system

Secondary- problem with the immune system because of underlying disease

Question 15

What does having a primary immunodeficiency increase risks of?

Answer 15

Infection
Autoimmunity
Inflammation
Atopic conditions
Malignancy

Question 16

Common exam related question but a bit random!

If a question asks about delayed separation of the umbilical cord, which cell is deficient?

Answer 16

Phagocytes

Question 17

List some of the factors that may make you think a patient has a primary immunodeficiency.

Answer 17

FH
Recurrent or chronic infections
Infections with unusual organisms e.g. PJP, NTM
Early onset eczematous skin rashes
Early onset autoimmuinity
Failure to thrive

Question 18

If a person is getting recurrent mucosal infections, which immunoglobulin is probably deficient?

Answer 18

IgA

Question 19

What is done in the management of primary immunodeficiency?

Answer 19

Prophylactic antimicrobials

Immunoglobulin replacement

Sometimes stem cell transplants

Question 20

What is the most common primary immune deficiency?

Answer 20

Primary antibody deficiency

Question 21

When do patients with primary antibody deficiency tend to present?

Answer 21

Usually after age 10

Question 22

Okayyy just for awareness.

Which primary antibody deficiencies present in neonatal period?

Answer 22

Transient hypogammaglobulinemia of infancy
X-linked agammaglobulinemia
Hyper IgM syndromes

Question 23

Okayyy just for awareness.

Which primary antibody deficiencies present in ages 4-15?

Answer 23

Hyper IgM syndromes
Common variable immunodeficiency
Selective IgA deficiency
Selective/partial antibody deficiency

Question 24

Okayyy just for awareness.

Which primary antibody deficiencies present in ages 1660?

Answer 24

Common variable immunodeficiency
Selective IgA deficiency
Selective/partial antibody deficiency

->so basically, hyper IgM syndromes present until mid teens, others can be earlier or later

Question 25

Which type of infections do patients with antibody disorders usually present with?

Answer 25

Recurrent sinus/chest infections

->history of repeated ENT surgery, bronchiectasis in young people
A second system is usually involved, e.g. skin sepsis (boils, abscesses), gut infections, meningitis

Question 26

Which immunoglobulin crosses the placenta?

Answer 26

IgG

Question 27

Okay he said to remember this example.

What would be seen in someone with common variable immunodeficiency upon testing?

Answer 27

Low serum IgG and IgA
Normal/reduced IgM
Normal B cells

Question 28

Management of common variable immunodeficiency?

Answer 28

Immunoglobulin replacement

Question 29

Which syndrome will occur if a patient does not have a thymus?

Answer 29

Di George syndrome

->T cell are made in the thymus

Question 30

In Di George syndrome, which cell count will be low?

Answer 30

CD3 cells

Question 31

Features of Di George Syndrome are best remembered by the pneumonic CATCH22.

What is meant by CATCH22?

Answer 31

Cardiac defects
Abnormal faces
Thymic aplasia
Cleft palate
Hypoparathyroidism

->variable T cell quantities, normal B cell levels

Question 32

What is the classic triad of symptoms for Wiskott-Aldrich Syndrome?

Answer 32

Immunodeficiency - recurrent pyogenic infection
Thrombocytopenia- bleeding
Eczema

Question 33

Another one he recommends learning.

What is SCID?

Answer 33

Severe combined immunodeficiency

->one of few immunological emergencies

Question 34

How does SCID present?

Answer 34

Infections within first few months of life
Failure to thrive
Immune dysregulation

Often will have chronic diarrhoea

Question 35

What is the diagnostic feature at birth of SCID?

Answer 35

Absolute lymphocyte count <2x10 to the power of 9

->worrying as children usuakky have a higher lymphocyte count than adults so something this low is worrying. Must exclude HIV though as this is commoner.

Question 36

Treatment for SCID?

Answer 36

Stem cell transplant- lifesaving

Question 37

What screening test is done to identify SCID at birth?

Answer 37

Heel prick test

Question 38

Secondary immune deficiencies are either caused by a lack of immunoglobulin production or an increased immunoglobulin loss.

What can cause a decrease in immuno production?

Answer 38

Malnutrition
Drugs
Malignancy
Infections

Question 39

Secondary immune deficiencies are either caused by a lack of immunoglobulin production or an increased immunoglobulin loss.

What can cause an increase in immuno loss?

Answer 39

Nephrotic syndrome
Burns
Protein-losing enteropathy