immune deficiency syndromes Flashcards
x linked agammablobulinemia path
failure of B cell precursors to become B cells
x linked agammaglobulinemia caused by defects in
bruton tyrosine kinase
key findings in x linked agammaglobulinemia
- absent mature B cells
- underdeveloped germinal centers
- absence of all antibodies
selective IgA syndrome due to
defect IgA B cells
in selective IgA syndrome blood transfusions leads to
anaphylaxis
special features of selective IgA syndrome
positive B HCG test
common variable immunodeficiency due to
defect B cells maturation and loss of plasma cells & antibodies
common variable immunodeficiency labs
normal B cells, absence of a antibodies
key difference of common variable immunodef
not x linked, later onset
B cells are only decreased in
x linked agammaglobulinemia
thyme aplasia is due to
failure of 3rd/4th pharyngeal pouch to form
digeorge syndrome due to
22q11 chromosome deletion
classic sxs of digeorge
catch 22
cardiac abnormalities
abnormal facies
thyme aplasia
cleft palate
hypocalcemia
22 chromosome
digeorge syndrome CXR
no thymic shadow
what is seen in digeorge syndrome?
underdeveloped T cell structures including paracortex in LN and peri-arteriolar sheaths in spleen
hyper IgE syndrome due to defective
Th17 cells and loss of attraction of neutrophils
hyper IgE has over production of __ & loss of __
IgE & INF gamma
classic findings in hyper IgE
deformed face/teeth
diffuse rase
cold skin abscesses
recurrent infections without fever
clinical mucocutaneous candidiasis due to defect in
regulator AIRE genes
aire function 1: associated iwht
dectin 1 receptor
dectin 1 response to
candida antigens
aire function 2: promotes
self antigen production in thymus
sxs of chronic mucocutaneous candidiasis
candida infections
endocrine dys
__ cells are imp for mucosal defense of candida
T cells
severe combined immunodeficiency loss of
cell mediated & humoral immunity
SCID shows loss of
thrymic shadow & germinal centers
SCID can be caused by
adenosine deaminase def
classic case of scid
infant with recurrent infections
absent thymic shadow
normal calcium/heart
adenosine deaminase def mech
excess dATP inhibits ribonucleotide reductase so DNA cannot be formed
ataxis telangiectasia
ATM gene chromosome 11
hyper IgM is due to
class switching disorder due to defect CD40L
wiskott Aldrich syndrome due to
x linked disorder with WASp absent
WASp is necessary for
T cell cytoskeleton maintenance
classic case of wiskott Aldrich syndrome
male
eczema
bleeding/petechiae (low platelets)
recurrent infections
leukocyte adhesion def due to
defective neutrophil/lymphocyte migration
leukocyte adhesion def is due to autosomal recessive defect in
CD18 causing issues with integrins (rolling phase)
key feature of leukocyte adhesion def
delayed separation of umbilical cord
chediak higashi syndrome due to
microtubule dys causing failure of lysosomes to fuse with phagosomes
chediak higashi gene mut
LYST (lysosomal trafficking regulator)
other common sxs of chediak higashi
oculocutaneous albinism (microtubules not presents to transport pigment)
chronic granulomatous disease loss of function of
NADPH oxidase
phagocytes use NADPH to generate
hydrogen peroxide for respiratory burst
five organisms that cause almost all of CGD infections
- staph aureus
- pseudomonas
- serratia
- nocardia
- aspergillus
what tests for CGD
nitro blue tetrazolium tests (in absence of NADPH cells do NOT turn blue)
