A/45

Question 1

Types of inherited immunodefficiencies (4)

Answer 1

• SCID
• X linked agammaglobulinaemia
• DiGeorge syndrome
• Isolated IgA deficiency

Question 2

What is SCID?

Answer 2

Defect in both humoral and cell mediated immunity because of impaired development of T and B cells

Question 3

Types of SCID

Answer 3

• X-linked (mostly affects boys)

- Autosomal recessive

Question 4

What causes X linked SCID?

Answer 4

Gamma chain mutation of IL2, IL4, IL7, IL9, IL15

Question 5

Why is IL7 important?

Answer 5

because it’s important for survival and expansion of immature B and T cells

Question 6

What causes autosomal recessive SCID?

Answer 6

adenosine deaminase mutation - defect in purine metabolism

Question 7

Treatment of SCID?

Answer 7

stem cell transplant

Question 8

What is X linked agammaglobulinaemia

Answer 8

• Pre-B/mature-B differenciation block

- absence of gamma globulin

Question 9

What causes x-linked agammaglobulinaemia?

Answer 9

Mutation of Bruton kinase gene

Question 10

What is DiGeorge syndrome?

Answer 10

Congenital deffect of thymic development

Question 11

What is the genetic deffect in diGeorge syndrome?

Answer 11

del22q11

Question 12

What does isolated IgA deficiency cause?

Answer 12

recurrent airways and GI infection (because that’s where IgA is most important)

Question 13

What causes isolated IgA deficiency?

Answer 13

Block of terminal differenciation of B cells into plasma cells

Question 14

What can cause acquired immunodefficiency?

Answer 14

• Irradiation treatment
• Diabetes
• Immunosuppressive treatment
• AIDS