Allergy and Immunology Flashcards
treatment of wiskott-aldrich?
bone marrow transplant, or splenectomy
besides infections, what other findings can you have with CVID?
non-caseating granulomas in liver, spleen, lungs (can have hepatosplenomegaly); celiac-type sprue, polyarthritis, other autoimmune conditions, increased risk of lymphoma, increased risk of giardia infections
how do you treat cyclic neutropenia?
GCSF (autosomal dominant)
what other conditions are associated with Purine Nucleoside Phosphorylase deficiency SCID?
neurologic disorders, autoimmune hemolytic anemia, and thrombocytopenia
what type of vaccines should be avoided in children with SCID?
live-attenuated viruses?
what groups of people MUST be desensitized to penicillin for appropriate treatment?
pregnant women with syphillis, or person with neurosyphillis
what type of cancers are common with ataxia-telangeiectasia?
lymphoma or lymphocytic leukemias
what gene is associated with wiskott-aldrich?
Xp11.22
what are some examples of type 4 reactions
tuberculin sensitivity, some contact dermatitis (cell-mediated hypersensitvities - previously sensitized T-cells)
B-cell deficiencies cause what general type of infections?
recurrent sinopulmonary
what complement deficiency should you look for in someone with meningococcal meningitis?
C5-C9 deficiency
what type of mastocytosis does not have mast cells in the skin?
malignant: causes severe systemic symptoms, hepatosplenomegaly, lymphadenopathy
what type of blood should babies with SCID receives?
irradiated (to prevent GVHD from T-cell transfusion)
how long must children be off antihistamines before skin testing?
at least 72 hours, preferably longer
how do you diagnos chronic granulomatous disease?
nitroblue tetrazolium (NBT) test or dihydrorhodamine (DHR) oxidation (flow cytometry)
should children with HIV get MMR and varicella vaccines
yes! (no oral polio though)
what are some of the primary B-cell immunodeficiencies?
X-linked agamma/hypogammaglobulinemia, CVID, hyper-IgM
how do you treat hyper IgM?
IVIG and Bactrim (PCP prophylaxis)
what are the levels of T- B- and NK cells in ADA SCID?
NO t-, b- or NK cells
treatment for SCID?
bone-marrow transplant (to make Tcells) AND IVIG (to replace antibodies cause B-cell function is usually not restored)
by what age do children with transient hypogammaglobulinemia reach normal IgG levels?
3-4 years (only tx with IVIG before then if having recurrent severe infections)
what are first line tests for T-cell disorders?
flow cytometry and delayed type hypersensitivity (candida skin testing)
what other abnormalities are common with ADA SCID?
skeletal (cupping and flaring of costochondral junctions, pelvic dysplasia)
what are some signs and symptoms of serum sickness?
fever, skin rash, joint pain, lymphadenopathy, myalgias, proteinuria, itching, redness, urticaria, angioedema, nausea, vomiting
what problems does Job syndrome cause?
eczema, scoliosis, delayed dental exfoliation, fractures, recurrent skin infections/abscesses with strep pneumo, staph and h flu
can household contacts of children who are immunocompromised receive live vaccines?
yes they can receive MMR and varicella - they CANNOT receive oral polio and should not get flumist
what is the presentation for x-linked agammaglobulinemia?
boys around 1 yr of life with recurrent penumonia, otitis, sinusitis - small lymph nodes and tonsils
what are children with immunodeficiency at higher risk of?
malignancy
what antibiotics commonly cause serum sickness?
cefaclor and penicillin
complement deficiencies tend to cause what?
overwhelming sepsis
findings in ataxia-telangeiectasia?
cerebellar ataxia, oculocutaneous telangiectasia, immunodeficiency, high incidence of cancer, high sensitivity to ionizing radiation
what vaccines should be avoided in children on chemo/receiving BMT or with immunodeficiencies?
BCG, oral polio, MMR, varicella
what class of medicines is relatively contraindicated in those with severe anaphylactic allergies?
beta-blockers (can dampen response to epinephrine)
what immunodeficiencies are both cellular and humoral deficiencies?
SCID, wiskott-aldrich, ataxia-telangeiectasia, bloom syndrome, and nimegen breakage syndrome
what physical findings are seen in Job syndrome?
asymmetric face, broad nose, triangular jaw, prominent forehead
when do Type 1 hypersenstivity reactions usually start?
within one hour of exposure
what are clinical findings associated with wiskott-aldrich?
bleeding (esp after circ); staph infections, recurrent sinopulmonary infections, small platelets
how does ataxia-telangeiectasia present?
ataxia usually by age 5, then the telangiectasias form in bulbar conjunctiva, ears, neck, and elbows
infants with “complete” digeorge are at risk of what?
GVHD with blood transfusions (like SCID) - have NO t-cells and low b-cell fxn (most have “incomplete” with some t-cell and normal b-cell function)
what virus is x-linked lymphoproliferative disease (duncan syndrome) associated with?
EBV - can cause fulminant hepatitis, lymphoma, agranulocytosis, aplastic anemia,
what are the levels of T- B- and NK cells in x-linked SCID?
NO t-cells or NK cells. Some B cells but they do not function normally.
does a negative skin test indicated NO allergy?
yes
T-cell deficiencies cause what general type of infections?
opportunisitic
does the bone marrow produce normal B cells in X-linked agammaglobulinemia?
yes it makes normal precursors, but the cells do not mature properly, so not functional
what vaccine do you NOT give boys with x-linked agammaglobulinemia?
oral polio vaccine
how is ADA SCID transmitted?
autosomal recessive
when does the late phase of type 1 reactions start?
3-12 hours later, lasts hours to days
What metabolic form of SCID is most common?
adenosine deaminase deficiency (ADA) - 15-20% of SCID cases
what types of infections are seen with leukocyte adhesion defects?
recurrent necrotizing infections where body meets the environment (skin, mucosa, gut, lungs)
if a child presents with abdominal pain AND extremity swelling, what should you think of?
hereditary angioedema (can try and treat with e-aminocaproic acid or epinephrine)
how do you treat CGD?
BMT or prophylactic antibiotics/antifungals and interferon gamma if no match
which syndrome is a primary T-cell immunodeficiency?
DiGeorge
when you see a vasculitis, what type of hypersensitivity reaction should you think of?
type 3 (immune complex reactions)
what are the genes in Autosomal Recessive SCID associated with?
jak 3 kinase
what are first line tests for B-cell disorders?
quantitative immunoglobulins, response to vaccines
what is the most common form of SCID?
x-linked (50% of cases); only affects boys
what lab finding is associated with LAD?
leukocytosis (since cells can’t leave the bloodstream)
what physical findings is often associated with LAD?
delayed umbilical cord seperation (also have cigarette paper scarring)
what post-pneumonia finding is often seen with Job syndrome?
pneumatoceles
what causes the type 1 late reactions?
cytokine release triggered by the mast cells, leads to eosinophilic infiltrate
some causes of pneumonia in SCID?
CMV, RSV, PCP
what is the mnemonic for wiskott-aldrich?
EXIT : eczema, x-linked, immunodeficiency, thrombocytopenia
how is CGD usually inherited?
x-linked
what lab findings are found with ataxia-telangeiectasia?
increased alpha1-fetoprotein (AFP), increased CEA, low IgA and IgG possible
how do you treat X-linked agammaglobulinemia?
IVIG monthly
how do you test for LAD?
flow cytometry for CD18
can you develop serum sickness on a first exposure to a drug?
yes
what type of infections are seen in hyper IgM?
sinopulmonary infections, giardiasis, bacterial and viral meningitis
what chromosome is the gene for ADA on?
chromosome 20
what disease has recurrent sinopulmonary and cutaneous infections, partial oculocutaneous albinism, mild MR, and peripheral neuropathy?
Chediak-Higashi syndrome
does a positive RAST test or positive skin test indicated allergy?
no, only suggest
what lab finding is diagnostic for wiskott-aldrich?
small platelets
what are first line tests for phagocytic disorders?
CBC with diff and neutrophil oxidation (either NBT or DHR tests)
what are the primary findings in DiGeorge?
craniofacial abnormalities, heart defects, absent parathyroids, subclinical hypoparathyroidism, mental retardation is common
what should be the first screening tests for a complement deficiency?
CH50 (will be low) and C3/C4 levels
what type of infections do phagocytic disorders usually cause?
skin and organ abscesses
what is the first best measure to fight dust mite allergies?
zippered pillow and mattress covers, launder bed linens every other week ; could also reduce humidity
what is underlying cause of ataxia-telangeiectasia?
defect in ATM gene - leads to increased apoptosis and cell death
what is bloom syndrome?
small stature, teangiectasia, CNS abnormalities, immunodeficiencies, and increased leukemia risk
what are the lab findings with x-linked agammaglobulinemia?
severe deficiency of all immunoglobulins, no B-lymphocytes in blood or lymph tissue (but can find immature precursor cells)
how is hereditary angioedema inherited?
autosomal dominant (AD)
what causes hereditary angioedema?
C1 inhibitor deficiency
what lab finding is associated with Chediak-Higashi syndrome?
large neutrophil granules (fusion of primary and secondary granules)
what are type 2 hypersensitvity (cytotoxic) reactions?
autoantibodies bind to target cell receptors or fixed tissue antigens (SLE-related thrombocytopenia, leukopenia, autoimmune hemolytic anemia; also Goodpasture’s and myastenia gravis)
how do babies with SCID present?
eczematous skin changes, absent thymus, low white count, lung infections, diarrhea, failure to thrive
what other lab finding will you seen with hereditary angioedema?
low C2 and C4 levels (constantly being used up since there is no inhibition of C1)
how is hyper IgM inherited?
x-linked (poorer prognosis) or autosomal recessive
how do you treat serum sickness
usually supportive care (self-limited)
what types of infections do children with CVID have?
recurrent sinus and pulmonary (encapsulated bacteria)
what infections are common with ataxia-telangeiectasia?
sinopulmonary infections, bronchiectasis
what other diseases are people with C3 deficiency at risk for?
SLE, vasculitis, autoimmune diseases
how do children with ADA SCID present?
within months of birth with profound lympopenia, hypogammaglobulinemia, and recurrent infections (chronic candidasis, PCP pneumonia, CMV< EBV, varicella, severe enterovirus)
what causes the type 1 acute reaction?
mast cell degranulation leading to histamine release
what is hyper IgM syndrome?
deficiency of IgG and IgA but increased levels of IgM
how is the x-linked type different?
also some T-cell dysfunction (problems with CD40) - can present with PCP pneumonia
what is CVID?
deficiency of at least two classes of immunoglobulins or poor immunoglobulin function (no response to vaccination)
what gene is associated with X-linked (Bruton’s) agammaglobulinemia?
Xq22 - codes for bruton’s tyrosine kinase which is important for B cell maturation
what lab finding is often associated with Job syndrome?
elevated IgE
what are some examples of type 3 reactions?
vasculitis, serum sickness (from exposure to drugs), Ig autoimmune diseases (SLE, hashimoto’s, RA)
early infections in SCID?
chronic cutaneous candidasis, rotavirus, pneumonia
how does CGD present?
chronic and recurrent organ and skin abscesses
what is urticaria pigmentosa?
formation of a wheal on gentle stroking of the skin (darier sign)
what is the triad for Wiskott-Aldrich syndrome
eczema, thrombocytopenia, susceptibility to bacterial (encapsulated) and opportunisitic infections
serum sickness
allergic shiners
allergic rhinitis
chronic steroid use: buffalo hump, obesity, moon facies
vascular ring
urticaria
angioedema
DiGeorge: micrognathia, hypertelorism, low-set malformed ears, midline scar (from surgery), smooth philtrum
eczema from wiskott-aldrich: note diffuse locations
pneumatocele: can be associated with staph aureus pneumonias and hyper IgE syndrome (Job syndrome)
periumbilical infection: think of leukocyte adhesion deficiency (esp if high WBC)
what are the three main types of phagocytic disorders?
neutropenia, phagocyte chemotaxis disorders (leukocyte adhesion defects), and phagocyte killing disorders (Job syndrome, CGD, Chediak-Higashi)
