Immunodeficiency Syndromes

Question 1

x linked immunodeficiency disease

Answer 1

x linked agammaglobulinemeia
hyper-Igm
SCIDS
Wiskott Aldrich

Question 2

x linked agammaglobulinemia

Answer 2

failure of b cell precursors to develop into mature B cells

caused by mutation in Btk- required for Ig chain rearrangement in maturation

manifests around 6 months

normal t cell mediated reactions

Question 3

common variable immunodeficiency

Answer 3

hypogammaglobulinemias

normal number of b cells but cannot differentate into plasma cells

presentation normal to Brutons, but development is later and equal in both genders

Question 4

isolated IgA deficiency

Answer 4

1:600 european descent

low levels of serum and secretory IgA

increased risk of respiratory, GI, and urogenital tracts

Question 5

hyper IgM syndrome

Answer 5

defect in ability of helper T cells to deliver activating signals to B cells

IgM present but deficiency of G, A, and E\

majority are x linked w/ mutatino encoding CD40L

Question 6

treatment for humoral immunodeficiency

Answer 6

IVIg

100-400 mg/kg of body weight every 3/4 weeks

adjust dose to achieve rate of infection that is comparable to general population

Question 7

digeorge syndrome

Answer 7

failure of development of 3rd and 4th pharyngeal pouches- defect in thymus

loss of t cell mediated immunity

tetany d/t abnormal calcium, congenital heart defects

caused by 22q11 deletion

Question 8

severe combined immunodeficiency

Answer 8

inability of common lymphoid progenitors to differentiate into proB or proT cells

low or absent T and B cells

death occurs w/o bone transplantation

cauesd by x linked recessive deficiency in cytokine receptors (most common cause). can also be caused autosomal recessive adenosine deficiency

Question 9

wiskott-aldrich syndrome

Answer 9

low platelets, exema, and immune deficiency

low IgM, normal IgG, and elevated IgA and E

do not make Abs to polysaccharide Ags

progressive T cell depletion

bone marrow transplant curative

Question 10

complement deficiencies

Answer 10

C2 deficiency- no increased risk of infection, but increased autoimmune disease

c3- increased risk of bacterial infection

C5-9- increased susceptibility to neisseria infection

C1 inhibitor- hereditary angioedema- episodic edema of skin or mucosal surfaces d/t stress or trauma

Question 11

viral core of AIDS

Answer 11

capsid protein p24, 2 copies of genomic RNA, 3 viral enzymes (protease, reverse transcriptase, and integrase)

Question 12

p17

Answer 12

matrix protein surrounding core of HIV

Question 13

viral envelop of HIV

Answer 13

host derived studded w/ gp120 and gp41, critical for infectivity

Question 14

HIV genome

Answer 14

flanked by LTR regions required for initiation of transcription.

contains control regions that bind host transcription factors

gene products: gag, pol, env
gag- p24 capsid protein and p17 matrix
pol- reverse transcriptase
env- gp160, 120 (CD4 binding), and 41 (fusion)

Question 15

genes that are unique to HIV

Answer 15

vif- promotes replication

vpr- increases replication and infection of macrophages

vpu- promotes CD degradation and release of virions

tat- transcription activator

rev- regulator of viral gene expression

nef- negative effector- down regulates CD4 and MHC expressoin to protect cells from CD8

Question 16

HIV infection

Answer 16

infects CD4, DC, and macrophages

becomes established in lymphoid tissues

not detectable in

Question 17

mechanisms of immunodeficiency in HIV

Answer 17

direct cytopathic effect

colonization of lymphoid tissue leading to progressive destruction

chronic activation of uninfected cells leading to activation induced cell death

killing of infected cell by cytotoxic T cells

Question 18

seroconversion to HIV

Answer 18

detectable in 3-7 weeks

Question 19

HIV evading the host

Answer 19

mutations are frequent

virus has a glycan shield to prevent Abs

Question 20

category C conditions

Answer 20

CMV infection
mycobacterium avium
toxoplasmosis in brain
pneumocystis- p/ jirovecii
kaposis sarcoma- HHV8