Immunodeficiencies ( 5 star!!!!!) Flashcards
low levels of all immunoglobulins and reccurent bacterial infections after 6 mo
Bruton Agammaglobulinemia
What is defective in Brutons agammaglobulinemia
defective tyrosine kinase gene–> B-cell deficiency
inheritance of Brutons
X-linked recessive–> so BOYS only
recurrent sinus and lung infections + allergies, eczema, asthma; MC immunodeficency
IgA deficiency
tetany + recurrent viral, fungal, protozoal infections
DiGeorge Syndrome–> no thymus (T cells) and no parathyroids (hypocalcemia)
What is the main pathogenesis of DiGeorge
Failure of 3rd and 4th pharyngeal POUCHES to develop
3rd branchial/ pharyngeal pouch derivatives
- inferior parathyroids (dorsal wings)
2. Thymus (ventral wings)
4th branchial pouch derivative
- Superior parathyroid glands (dorsal wings)
Branchial pouches derived from what germ layer
endoderm
90% of DiGeorge have what chromosomal abberation
22q11 defect
what two heart defects may be seen in Digeorge
- tetralogy of fallot
2. truncus arteriosus
Chvostek sign
tap cheek and get a spasm –> hyopcalcemia; used in DiGeorge
Trousseau sign
tighten BP cuff around arm and get carpospedal spasm–> hypocalcemia spasm; seen in DiGeorge
T-cell dysfunction against Candid
Chronic Mucocutaneous Candidiasis
elevated IgM, but low IgG
Hyper IgM syndrome
X-linked Hyper IgM due to
no CD40-L on helper T-cells–> cant activate B-cells to class-switch
AR Hyper IgM due to
no CD40 on B-cells
*can also be due to NEMO deficiency
recurrent mycobacterial infections
IL-12 receptor deficiency
severe recurrent or fatal infections from common viruses, chronic diarrhea, failure to thrive
Severe Combined Immunodeficiency (SCID)
what is deficient in SCID?
adenosine deaminase–> no B-cells o T-cells
what does SCID have in common with DiGeorge
no thymic shadow on CXR–> T-cells arent made, so thymus not large
young boy with recurrent infections and eczema on the trunk
Wiskott-Aldrich syndrome–> is X-linked, so ALL are boys
4 symptoms of Wiskott-Aldrich (“WAITER”)
Wiskott Aldrich Immunodeficiency Thrombocytopenia and purpura Eczema Recurrent pyogenic infections
*thrombocytopenia= easy bleeding, so purpura
Lab findings in Wiskott-Aldrich (2, are Ig)
- low IgM (hence immune issues; can make IgM against capsular polysaccharides of bacteria)
- high IgA
young kid who can’t track moving targets with smooth pursuit, is maybe clumsy
Ataxia-telangectasia–> defects in DNA repair
clumsiness due to cerebellar ataxia
what are Ataxia-telangectasia pts deficient in (Ig)
deficient IgA
what serum value may be increased in Ataxia-telangectasia by 8 mo
AFP (alpha fetoprotein)
*( think “A” for Ataxia, AFP, IgA)
Ataxia-telangiectasia have increased risk of what two CA
- lymphoma
- acute leukemias
*dont get chronic; usually dead by age 25, so wont live long enough
what to avoid in Ataxia-telangiectasia pts
X-rays–> can’t repair DNA, so exquisitely sensitive to radiation of any kind
Chronic Granulomatous disease pts are deficient in what enzyme
NADPH oxidase–> phagocytes can phagocytose, but cant perform intracell killing = no generation of ROS
Test for Chronic Granulomatous disease?
Nitroblue tetrazolium NBT) test–> add dye to blood, usually NADPH will oxidize NBT from yellow to blue/black; no color change in CGD pt
chronic granulomatous pts are especiialy sensitive to pathogens with what–> 5 examples for bonus pts! (3 bact and 2 fungi)
Catalse + organisms:
- S. aureus
- E. coli
- Klebsiella
- Aspergillus
- Candida
Tx for chronic granulomatous dz
- prophylactic TMP-SMX
2. sometimes INF-gamma helpful, not always
partial albinism, neurologic disorders, recurrent respiratory tract infections and skin infections
Chediak-Higashi syndrome
what gene defective in Chediak-higashi
LYST gene–> lysosomal transport; cant get enzymes to lysosomes, so they dont work
what would be diagnostic of Chediak-Higashi on a blood smear
Giant cytoplasmic granules in PMNs
eczema, cold abcesses, and broad nose, frontal bossing, deep set eyes
Hyperimmunoglobulin E syndrome (Job syndrome)
think about Job covered in boils
what is deficient in Hyperimmunoglobulin E
IFN-gamma–> impaired neutrophil chemotaxis = hence the cold abcesses; cant get neutrophils there, so no imflammation, no warmth
delayed separation of umbilical cord (stay on for a month or more)
Leukocyte Adhesion Deficiency syndrome
what is defective in Leukocyte Adhesion deficiency syndrome
abnormal integrins–> inability of phagocytes to exit circulation
2 rows of teeth
Hyperimmunoglobulin E syndrome (Job syndrome)
