lecture 20 & 21-immune deficiencies

Question 1

when is an ADA immunodeficiency considered a combined immune deficiency

Answer 1

when it affects B, T, and NK cells

Question 2

what mutation and defect is X-linked agammaglobulinemia due to

Answer 2

BTK gene and defect in rearrangement of Ig heavy chain genes

Question 3

describe the level of Ig in X-linked agammaglubulinemia

Answer 3

low/absent IgG, IgA and IgM

Question 4

what is the main associated feature of X-linked agammaglubulinemia

Answer 4

severe bacterial infections

Question 5

what are the genetic defects of autosomal recessive agammaglubulinemia

Answer 5

mutations in mu, Ig-alpha, lambda5 genes and BLNK

Question 6

describe Ig levels of common variable immune deficiency

Answer 6

Low IgG and IgA. Normal/low IgM

Question 7

what is the typical onset of common variable immune deficiency

Answer 7

after 4-5 years of age

Question 8

what is the pathogenic mechanism involved in IgA secreting B cells

Answer 8

disorder of maturation or terminal differentiation

Question 9

describe Ig levels of IgA deficiency

Answer 9

low IgA. Normal IgG and IgM

Question 10

describe Ig levels of high IgM syndromes (HIGM)

Answer 10

high IgM. Low IgG and IgA

Question 11

what are HIGM characterized by

Answer 11

impaired Ig class switching and somatic hypermutation

Question 12

what are patients with HIGM syndromes more susceptible to

Answer 12

bacterial infection

Question 13

describe Ig levels for isolated IgG subclass deficiency

Answer 13

total IgG, IgM, IgA and IgE are normal

Question 14

what are low levels of IgG2 in children associated with poor responses to

Answer 14

poor responses to polysaccharide Ags

Question 15

what type of infections are common with isolated IgG subclass deficiencies

Answer 15

recurrent viral/bacterial infections, frequently in respiratory tract

Question 16

how long is intrinsic Ig production typically delayed in transient hypogammaglobulinemia of infancy

Answer 16

up to 36 months

Question 17

what is the resulting Ig concentration for transient hypogammaglobulinemia of infancy

Answer 17

low IgA and IgG concentration, IgM may be normal or low

Question 18

what do individuals with transient hypogammaglobulinemia of infancy have an increases susceptibility to

Answer 18

sinopulmonary infections

Question 19

what type of syndrome is wiskott-aldrich syndrome

Answer 19

X-linked with progressive decrease in T cells

Question 20

where is WASP expression limited to in wiskott-aldrich syndrome

Answer 20

hematopoietic lineage

Question 21

what are the main clinical manifestations of wiskott-aldrich syndrome

Answer 21

thrombocytopenia, eczema and susceptibility to infections, bruising

Question 22

describe the Ig concentration for wiskott-aldrich syndrome

Answer 22

Low IgM: IgG normal. IgA and IgE elevated

Question 23

what recurrent infections are common with wiskott-aldrich syndrome

Answer 23

encapsulated bacterial infections

Question 24

what is the most common form of SCID

Answer 24

common gamma chain deficiency

Question 25

what type of deficiency is common gamma chain deficiency

Answer 25

X-linked

Question 26

what type of deficiency is adenosine deaminase deficiency (ADA)

Answer 26

autosomal recessive

Question 27

what is ADA especially essential for

Answer 27

metabolic function of T cells

Question 28

what does ADA lead to accumulation of

Answer 28

toxic metabolic by-products: adenosine and deoxy-ATP

Question 29

what type of trait is deficiency of Jak3 due to

Answer 29

autosomal recessive trait

Question 30

what type of receptor signaling does deficiency of Jak3 cause

Answer 30

defect in IL-2 receptor signaling

Question 31

what type of deficiency is Digeorge syndrome due to

Answer 31

T-cell deficiency

Question 32

what is the key biological feature of DiGeorge syndrome

Answer 32

hypocalcemia

Question 33

what does neonatal hypocalcemia typically present as in Digeorge syndrome

Answer 33

tetany or seizures

Question 34

what are MHC I deficiencies caused by

Answer 34

inability of TAP1 molecules to transfer peptides to ER

Question 35

what is the most frequent phagocytic primary immunodeficiency

Answer 35

chronic granulomatous disease

Question 36

what is the biochemical cause of chronic granulomatous disease

Answer 36

enzymatic deficiency of NADPH oxidase in phagocytes

Question 37

what does the deficiency in chronic granulomatous disease result in

Answer 37

defective elimination of extracellular pathogens such as bacteria or fungi; formation of granulomas

Question 38

what are patients with chronic granulomatous disease particular susceptible to recurrent infections with?

Answer 38

catalase-positive organisms (ie: staphylococci)

Question 39

what type of disorder is Chediak-higashi syndrome

Answer 39

autosomal recessive

Question 40

what is the diagnostic criterion for chediak-higashi syndrome

Answer 40

No NK activity and partial albinism

Question 41

what are the granules of chediak-higashi syndrome missing

Answer 41

no cathepsin G and elastase

Question 42

what type of infections are individuals with chediak-higashi syndrome prone to

Answer 42

recurrent pyogenic infections with bacteria

Question 43

What type of disease is G6PD deficiency

Answer 43

X-linked recessive hereditary disease

Question 44

what is G6PD deficiency mostly due to

Answer 44

lack of substrate for NADPH

Question 45

what is leukocyte adhesion deficiency mostly due to

Answer 45

mutation and lack of expression of LFA-1

Question 46

what is the major clinical manifestation of leukocyte adhesion deficiency

Answer 46

delayed detachment of the umbilical cord

Question 47

how do abnormalities in early components of the classical complement pathway typically manifested

Answer 47

SLE (but sometimes recurrent sinopulmonary infections)

Question 48

what do people who have deficiencies of the alternative complement pathway usually present with

Answer 48

neisserial and other bacterial infections

Question 49

what is factor H deficiency associated with

Answer 49

atypical hemolytic uremic syndrome or glomerulonephritis

Question 50

what does C1 esterase inhibitor deficiency cause

Answer 50

hereditary angioedema

Question 51

what type of patients typically have decay accelerating factor defects

Answer 51

those with paroxysmal nocturnal hemoglobinuria

Question 52

what is the best test for screening for defects in the classical complement pathway

Answer 52

total hemolytic complement activity (CH50) assay

Question 53

what is the best test for screening for defects in the alternative complement pathway

Answer 53

AH50 assay