Immunodeficiencies Flashcards
X-Linked (Bruton) Agammaglobulinemia (what it is, what you get)
Defect in BTK, a tyrosine kinase, no B cell maturation, XLR (so in Boys)
Get recurrent bacterial and enteroviral infections after 6 months (bc lose maternal IgG)
No B cells/absent/scanty Lns/tonsils
Selective IgA Deficiency (epi and 5 As)
Most common primary immunodeficiency
Majority Asymptomatic, but can see Airway/GI infections, Autoimmune disease, Atopy, Anaphylaxis to IgA-containing products (anaphylaxis to blood products)
Thymic Aplasia (DiGeorge Syndrome) (genetics, what it is, findings and CXR)
Usually 22q11 deletion, failure to develop 3rd and 4th pharyngeal pouches so absent thymus and parathyroids
Get hypocalcemia/tetany (Chvostek’s and Trousseau’s signs), recurrent viral/fungal infections, and conotruncal abnormalties like ToF, truncus arteriosus, transposition of great vessels
Absent thymic shadow on CXR
IL-12 R Deficiency
Decreased Th1 response, so disseminated MYCOBACTERIAL and fungal infections
Autsomal Dominant Hyper-IgE Syndrome (Job Syndrome) (what it is, triad + one unique finding))
Deficiency of Th17 genes due to STAT3 mutation (decreasd IFN-gamma?) so impaired recruitment of nphils to sites of infection
Triad: Eczema, recurrent cold (noninflammed bc nphils not recruited) abscesses (usually staph), corase facies
Also retained primary teeth so 2 layers
Chronic Mucocutaneous Candidiasis
T cell dysfunction so get noninvasive C. albicans infections of skin and mucous membranes
Severe Combined Immunodeficiency (2 kinds/inheritances, triad, tx, CXR)
Most common, XL: Defective IL-2R gamma chain
AR: Adenosine deaminase deficiency
Triad: Failure to thrive, chronic diarrhea, severe recurrent infections. Need BM transplant (no risk of rejection)
Absence of thymic shadow (also no germinal centers or Tcells)
Ataxia-telegiectasia (what it is, 4 As, risk and consideration)
Defects in ATM gene so failure to repair dsDNA breaks and cell cycle arrest
Ataxia (cerebellar defects, poor smooth pursuit), spider Angiomas (telangiectasia, after age 5), IgA deficiency, increased AFP
Increased cancer risk so need to AVOID RADIATION early
Hyper-IgM Syndrome (what it is, what you get)
Most commonly due to defective CD40L on Th cells (XLR) so class switching defect. Get lots of IgM but less everything else. Get severe pyogenic infections early in life, opportunistics with Pneumocystis, Cryptosporidium, CMV
Wiskott-Aldrich syndrome (what it is, what you get, Ab changes)
Mutation in WAS gene (XLR), T cells unable to reorganize actin cytoskeleton
WATER: Wiskott-Aldrich: Thrombocytopenia, Eczema (truncal), Recurrent infections. Decreased IgM so at risk for encapsulateds, increased IgA
Leukocyte adhesion deficiency (type I) (what it is, what you get, big sign)
Defect in LFA-1 integrin on phagocytes so impaired migration/chemotaxis, AR
Recurrent bacterial skin and mucosal infections but absent pus and impaired wound healing
DELAYED SEPARATION OF UMBILICAL CORD (>30 days)
Chediak-Higashi syndrome (what it is, triad, histo finding)
Defect in lysosomal trafficking regulator gene (LYST)
MT dysfunction in phagosome-lysosome fusion (AR)
Triad: Partial albinism, recurrent resp/skin infections, NEURO disorders - peripheral or otherwise
Giant granules in granulocytes and platelets
Chronic Granulomatous Disease (what it is, what you get, diagnostic test, treatment)
Defect of NADPH oxidase, so decreased ROS (superoxide) and decreased resp. burst in nphils. XLR most common
Increased suscepitbility to CATALASE POSITIVE organisms: KNeed PLACESS - Klebsiella, Nocardia, Pseudomonas, Listeria, Aspergillus, Candida, E. Coli, S. aureus, Serratia
Nitroblue tetrazolium dye reduction test is NEGATIVE - doesn’t oxidize the dye to blue/black
Tx: Prophylactic TMP and IFN-gamma
