Immunodeficiency

Question 1

What are primary immunodeficiencies

Answer 1

Inherited
- X linked
- Autosomal recessive
- Autosomal dominant

Question 2

What are secondary immunodeficiencies

Answer 2

Acquired from oter conditions like infection, autoimmune disease, malignancies, therapy

Question 3

What is affected by primary immunodeficiencies

Answer 3

• Humoral immunity: defects in B or Th cells
• Cell mediated immunity: T cell deficiencies
• Innate immunity: PMN, macros, complement

Question 4

Nine categories of PIDs

Answer 4

1. Combined IDs
2. Combined IDs with associated or syndromic features
3. Predominantly Ab deficiencies
4. Disease of immune dysregulation
5. Congenital defects of phagocyte number, function, or both
6. Defects in innate immunity
7. Autoinflammatory disorders
8. Complement deficiencies
9. Phenocopics of primary immunodeficiencies

Question 5

Predominantly antibody deficiencies: X lined bruton’s tyrosine kinase deficiency

Answer 5

No maturation at pre b cell stage
- Lack of mature CD19 B cells in blood and plamsa cells in lymphoid tissues

Question 6

Predominantly antibody deficiencies: common variable immunodeficiency

Answer 6

• Heterogenous group
• Congenital/acquired, symptoms later age
• B cells fail to mature into plasma cell

Question 7

Predominantly antibody deficiencies: transient hypogammaglobulinemia of infancy

Answer 7

• Delayed Ig development/production (IgG)
• Delayed Th maturation

Question 8

Predominantly antibody deficiencies: selective IgA deficiency

Answer 8

Most common immunodeficiency
- low IgA, less differentiation to IgA plasma cells
- Can be asymptomatic or more susceptible to infections

Question 9

Combined immunodeficiencies

Answer 9

• Involve a T cell deficiency

Question 10

Severe combined immunodeficiency disease (SCID)

Answer 10

• Group of PIDs
• T cell development defect
• X linked recessive, autosomal recessive
• RAG 1 or RAG 2: regulate recomb of TCR and Igs

Question 11

Wiskott Aldrich Syndrome

Answer 11

X linked recessive PID
- eczema, ID, thrombocytopenia
- Defective T function
- Low IgM and increased IgE

Question 12

DiGeorge Anomaly

Answer 12

Developmental abnorm. in pharyngeal pouches in embryo
- Underdeveloped thymus, low T cells
- Deletion in chromosome 22
- thyroid issues
- Cognitive delays
- Abnormal facial features

Question 13

Ataxia Telangiectasia

Answer 13

Autosomal recessive syndrome
- Involuntary muscle movements
- Mutation in AT gene on chromosome 11
- Defective DNA repair and gene rearrangements on T/B cells

Question 14

Chronic granulomatous disease (CGD)

Answer 14

Defect in phagocytic cell function
- X linked recessive OR autosomal recessive
- Neutrophils NO oxidative burst