Primary immunosuppression

Question 1

Where do T-lymphocytes develop?

Answer 1

Thymus

Question 2

Where do B-lymphocytes develop?

Answer 2

Bone marrow

Question 3

What are consequences of immunodeficiency?

Answer 3

Susceptiblity to infections
Susceptibility to cancer
Increased incidence of autoimmunity

Question 4

What causes primary immunodeficiency?

Answer 4

Genetic or congenital disorders

Question 5

What abnormalities can be caused by primary immunodeficiency?

Answer 5

Part of immune system is missing or not functioning properly

Question 6

Where can abnormalities be in primary immunodeficiency?

Answer 6

Innate immune system
Stages of lymphocyte development
Responses of mature lymphocytes to antigenic stimulation

Question 7

What happens as a result of agammaglobulinaemias?

Answer 7

Decrease in all serum Ig isotypes

Reduced B cell numbers

Question 8

What infections are people with B cell deficiency susceptible to vs people with T cell deficiency?

Answer 8

B - Pyogenic bacteria, Enteric bacteria and viruses, some parasites
T - Pneumocystis jiroveci, viruses, atypical mycobacteria, fungi

Question 9

What are causes of primary immunodeficiency?

Answer 9

Mutations
Polymorphisms
Polygenic disorders

Question 10

What is a polymorphism?

Answer 10

Change in one of two or more variants of a particular DNA sequence

Question 11

What is a polygenic disorder?

Answer 11

Disorder caused by combined action of more than one gene

Question 12

What is SCID?

Answer 12

Severe Combined ImmunoDeficiency - disorders that affect both T and B cells

Question 13

Is SCID screened for?

Answer 13

Yes

Question 14

What alleles can cause polymorphic conditions?

Answer 14

Human leukocyte antigen

Mannan-binding lectin

Question 15

What are common polygenic disorders affecting immunity?

Answer 15

Common variable immunodeficiency
IgA deficiency
Specific antibody deficiency

Question 16

How is SCID diagnosed?

Answer 16

Clinical presentation - Recurrent infection, unusual infections, diarrhoea, rashes
History - FH of neonatal death or consanguinity
Very low lymphocyte count

Question 17

How is antibody deficiency diagnosed?

Answer 17

Presentation - Presents later in life, chronic or recurrent bacterial rresp infection
Antibody levels - Measure IgG, IgM, and IgG, exclude causes of secondary immunodeficiency

Question 18

How is primary immunodeficiency treated?

Answer 18

Antibiotic prophylaxis

Immunoglobulin replacement therapy if severe