Immunodeficiency

Question 1

DiGeorge syndrome

Answer 1

Failure of development of 3rd and 4th pharyngeal pouches, leads to lack of thymus (among other defects), failure in development of T cells

Question 2

X-linked SCID

Answer 2

Deficiency of common gamma chain (common to ILRs such as IL-2,4,7,9, and 15 receptors). Deficiency prevents T-cells from developing properly (IL-7 required for T-cell development)

Question 3

Autosomal SCID

Answer 3

RAG (Recombination activating genes) deficiency or ADA (adenosine deaminase) and PNP (purine nucleoside phosphorylase) deficiency preventing proper maturation of T-and B-cells. Loss of RAG prevents proper VDJ rearrangement, loss of ADA, PNP leads to toxic buildup of purine metabolites in developing cells

Question 4

What is the hallmark symptom in T-cell deficient patients?

Answer 4

Candida albicans (white stuff in mouth of patient)

Question 5

Bare lymphocyte syndrome

Answer 5

Deficiency of MHC Class II leading to failure of activation of T-cells

Question 6

Chronic mucocutaneous candidiasis

Answer 6

Failure to develop Th1 responses, mechanism unknown, often seen during pregnancy

Question 7

X-linked hyper-IgM syndrome is caused by a CD40 ligand mutation. In this case what cells can helper T-cells not properly activate?

Answer 7

Macrophages and B-cells

Question 8

Name how glucocorticoid administration affects counts of: neutrophils, lymphocytes, eosinophils, monocytes, and basophils

Answer 8

Increases neutrophil count but decreases all the others. Values return to normal levels after about 24 hours

Question 9

X-linked agammaglobulinemia (give cause, pathology and result)

Answer 9

B-cell Tyrosine Kinase (BTK) deficiency prevents proper maturation of B-cells, leads to pyogenic infections

Question 10

Does removal of the spleen affect the T-cell response, B-cell response, or both?

Answer 10

Mainly the B-cell response

Question 11

List 5 disorders you can get with failure of complement and the deficiency that causes each

Answer 11

Immune-complex deficiency (C1, C2, C4), Angioedema (C1 inhibitor), Recurrent pyogenic infections (C3, Factors H and I), Recurrent Neisseria infections (C5-C8, properdine, Factor D), asymptomatic (C9)

Question 12

Leukocyte Adhesion Deficiency (LAD-1)

Answer 12

Mutations in selectins or integrins, preventing leukocytes from properly being slowed and extravasating

Question 13

Chronic granulomatous disease can reflect a mutation in what?

Answer 13

Mutation in phagocyte oxidases, failure to kill phagocytosed microbes leading to granuloma formation

Question 14

Serum Ig levels in ADA and PNP deficiencies

Answer 14

ADA deficiency - Decreased Ig levels, PNP deficiency - normal serum Ig levels (both deficiencies cause SCID however)

Question 15

What is WASP and what does it do?

Answer 15

Wiskott-Aldrich synthetic protein. Binds adapter molecules and cytoskeletal proteins, deficiency leads to failure of T-cell development

Question 16

Ataxia-telangiectasia

Answer 16

AR disorder with deficiency in cell-mediated immunity and IgA and IgG2. Caused by defect in DNA repair during VDJ recombination

Question 17

What is the hallmark sequela of ALPS?

Answer 17

Autoimmune Glomerulonephritis (overactive immune system attacks kidney)

Question 18

What type of immunity is compromised by severe burns and multiple trauma?

Answer 18

Innate immunity

Question 19

Chronic renal disease is asssociated with decreased migration of what type of cell?

Answer 19

Neutrophils

Question 20

Besides HIV, what is another virus which greatly suppresses the immune system?

Answer 20

Measles

Question 21

What is the most common Ig isotype deficiency?

Answer 21

Selective IgA deficiency (is most comon immunodeficient disorder)

Question 22

Pts with selective IgA deficiency often develop what type of hypersensitivity disease?

Answer 22

Type III