deck 1

Question 1

What is a type I reaction?

Answer 1

occur promptly after sensitized individual is exposed to an antigen, mediated by specific IgE antibody. cross-plinking of IgE on the surface of mast cells an basophils lead to histamine release/other inflammatory mediators release
examples: immediate hypersensitivity - allergic rhinitis and urticaria
anaphylactoid reactions - similar, but caused by degranulation of mast cells ann basophils WITHOUT specific IgE

Question 2

What is Type II reactions?

Answer 2

Antibody against antigen components of blood or tissue cells or foreign antigens, results in cell destruction.
can be IgM, IgG or IgA antibodies, they bind to the cell surface and activate the entire complement pathway , triggers mast cell degranulation, leads to inflammatory mediator release
examples: autoimmune hemolytic anemia and Rh/ABO hemolytic disease of the newborn; other examples (from baby Nelson): thrombocytopenia, basement membrane molecules in the kidney (GOodpasture), myasthenia gravis, Graves disease
IgG or IgM involved, complement is the mediator

Question 3

What are type III reactions?

Answer 3

antigen-Ab complexes form, deposited in the lining of blood vessels, and filtering organs (i.e. liver, spleen, kidney)
activate the complement cascade, recruit neutrophils, leads to inflammation
ie: serum sickness and immune complex-mediated renal diseases (i.e. PSGN), also hypersensitivity pneumonitis
complement and anaphylatoxin are mediators
Timing (baby nelson ) 1-3 hours after drug exposure (i.e. for serum sickness), arthrus reaction can happen earlier after

Question 4

Type IV reactions?

Answer 4

involve T cell-mediated tissue inflammation and typically occur 24-48 hours after exposure (baby Nelson says 2-7 days after drug exposure)
ie: tuberculin reactions, contact dermatitis , graft vs host disease
lymphocytes involved, cytoins are mediators (include IFN alpha, TNF, alpha, GMCSF)

Question 5

What is the best biological marker for anaphylaxis?

Answer 5

tryptase, although it is still rather insensitive
early mediators of anaphylaxis: histamine, tryptase, chymas, heparin, proteases
late mediates: prostaglandings, leukotriene and cytokines

steps of type I hypersensitivity:
develop depends on :
hereditary predisposition, sensitization by exposure, subsequent reexposure to the antigen
IgE towards specific allergens bound o receptors on mast cells an dbasophils, cell gets activated by cross linking IgE antibodies and leads to the release of mediators

Question 6

Examples of type I hypersensitivity

Answer 6

alergic rhinitis (most common)
urticaria
anaphylaxis (most severe)

Question 7

How is type I hypersensitivity diagnosed?

Answer 7

skin testing
percutaneous skin test - in vivo method to detect IgE antibody to specific allergens ; how it works, the IgE cross links and causes mast cell degranulation leads to histamine release
skin prick test - safest and most specific test: correlates best with symptoms
- interpret by measuring maximal diameter of wheal and flare 15-20 minutes after infecting with the allergen (via prick/puncture or intradermal infection)
- intradermal thought to be more sensitive than prick tests, but specificity is poor , should only use when ruling out allergic disease is essential (i.e. skin prick test is better)
- compare with negative control (saline) and positive control (histamine)

Question 8

What are 4 contraindications to allergic skin testing:

Answer 8

1) recent use of anti-histamines (histamine control will be negative)
2) skin disease limits the area available for testing (i.e. dermatographism or extensive dermatitis)
3) during an asthma exacerbation or episode of anaphylaxis
4) when a patient is taking a beta blocker, because this could interfere with epi to treat test-induced anaphylaxis

in these cases, in vitro testing is a good alternate
can do with a few millilitres of blood

Question 9

Which are more sensitivite, in vitro tests or skin prick tests for allergy?

Answer 9

in vitro tests are
1) less sensitive than allergy prick tests (especially less sensitive for aeroallergens, drugs and hymenoptera)
2) more expensive than allergy prick tests
see table on pg 113 for comparisons
also, in vitro not affected by any drugs, including steroids, vs skin test will be affected by antihistamines and not usually affected by corticosteroids**
(also baby nelson pg 273 comparison)

Question 10

What organ is most commonly involved in anaphylaxis?

Answer 10

the skin

Question 11

True or false - skin testing is commonly affected by steroids

Answer 11

false - not commonly affected by steroids

Question 12

True or false - life-threatening reaction to hymenoptera is common in childhood

Answer 12

false - not common in childhood, compared to common opinion.

most common are large local reactions or generalized urticaria

Question 13

A child presents with a large local reaction after a bee sting. The parents want to know how long it will last. What do you tell them?

Answer 13

• continuous with sting, starts 12-24 hours after sting, peaks in 2-3 days, lasts 1 week and should be treated with antihistamines and NSAIDs

Question 14

The same parents want to know if their kid needs an epi pen.

Answer 14

excellent long-term prognosis, do not need allergy testing, do not need to carry epi
**the risk for systemic anaphylaxis from stinging insets in children with symptoms confined only to the skin is equal to the risk in the general population

Question 15

Two day’s later, the child’s sibling presents with generalized urticaria after a bee sting. They really need to get rid of the bees. Does this kid need epi?

Answer 15

Yes, at present, the consensus among allergists suggests that children with a history of generalized urticaria from stinging insects carry epi

these kids don’t need skin testing or desensitization

**ps all from Zitelli

Question 16

That night on call, the neighbour of the first two kids arrives with an anaphylactic reaction. After he is stabilized and being prepared for discharge, what do you tell the parents about follow up and treatment ?

Answer 16

anaphylaxis after sting: should get allergy testing and if positive, should get immunotherapy
testing should be done 4 or more weeks after reaction (if you do it too soon, risk of false negative)
immunotherapy protects from anaphylaxis in 95-100% of patients (for wasps, yellow jackets,hornet etc), less for honeybees (80%)

(unrelated immunotherapy also works for desensitization of pollens, dust mites, and cat and dog proteins)

Question 17

What bug is the most common cause of hymenoptera anaphylaxis in US

Answer 17

yellow jackets

Question 18

What are the two big categories of food allergy? (zitelli figure 4-9)

Answer 18

1) IgE mediated hypersensitivity (anaphylaxis, oral allergy)

2) non IgE mediated

Question 19

What are some examples of non igE mediated food allergy?

Answer 19

• food protein enteropathy, milk protein enterocolitis, lactose intolerance

from either mechanism: eosinophilic gastroenteritis, atopic dermatitis

Question 20

True or false - most kids will outgrow type I reactions to milk and egg

Answer 20

true - these reactions usually more mild (i.e. urticaria) and in first year of life, usually outgrow them

Question 21

What percentage of kids will outgrow a type I hypersensitivity peanut allergy?

Answer 21

<25%

Question 22

What is oral allergy syndrome?

Answer 22

aka pollen food syndrome
patients have underlying seasonal allergic rhinitis and develop pruritus and angioedema of the oropharynx when ingesting fresh fruits and veggies - cross reactivity between proteins in some fruits and veggies and outdoor seasonal pollens , can eliminate the reaction by heating the veggie/fruit

Question 23

True or false - milk protein enterocolitis is IgE mediated

Answer 23

no, bloody diarrhea in few months, improves with removing milk proteins front eh diet.
non IgE mediated so neither allergy skin prick nor in vitro helps (i do think there is aIgE form too, will need to read more about this)

Question 24

What is the time of onset of each of the hypersensitivity types?

Answer 24

type 1: <30 min (immediate) 2-12 hours (late phase
type II: minutes/hours
III: 4-8 hours
IV: delayed type 24-48 hours

Question 25

what is the major determinant in penicillin?

Answer 25

once penicillin enters the body, it is converted to a reactive intermediate, binds to nearby proteins, forming penicilloyl amides these are called the major antigenic determinant small amount is in the body as a minor determinant Skin testing with the major determinant, penicillin and minor determinant - negative predictive value of 100% , 10-20% of skin tests from minor determinant

Question 26

How long after drug exposure does serum sickness start?

Answer 26

1-3 weeks after drug exposure, involves fever, malaise, arthralgia, arthritis, urticaria, lymphadenopathy many patients have a characteristic serpiginous, erythematous or purpuric rash decreased C3 and C4, immune complexes triggers (baby Nelson): blood products, foreign proteins (i.e. antithymocyte globulin and antivenins) medications: penicillin, sulfonamides, minocycline, cefaclor, hydantoins, thiazides can happen more soon in a patients who was previously sensitized rare complications: carditis, GN, Guillain Barre, encephalomyelitis, peripheral neuritis

Question 27

What is the treatment for serum sickness

Answer 27

baby Nelson: self-limited should resolve in 1-2 weeks, treatment is symptomatic antihistamines for pruritus, NSAIDS for fever and joint pain , if needed can give prednisone allergy skin testing doesn't predict serum sickness antihistamines steroids if doesn't work should resolve within a few weeks

Question 28

Common trigger for TEN

Answer 28

almost always drug induced

Question 29

Comon trigger for SJS

Answer 29

drugs (1-3 weeks before) infection: mycoplasma, HSV no universal therapy: some say IVIG

Question 30

Can we use steroids for SJS?

Answer 30

no, relatively contraindicated some studies have shown a deleterious effect

Question 31

What is DRESS syndrome?

Answer 31

drug rash with eosinophilia and systemic symptoms initially described with anti-convulsant therapy start 2-6 weeks after therapy rash, fever, increased eosinophils, multi organ dysfunction LVR most commonly involved, steroids not well studied

Question 32

What is the most common cause of chronic urticaria?

Answer 32

idiopathic (in contrast to acute) chronic has to last at least 6 weeks

Question 33

Which part of the complement cascade is defective in hereditary angioedema?

Answer 33

automsomal dominant disorder absence/abnormal function of a protein int eh complement cascade known as C1 esterase inhibitor recurrent bouts of swelling, most often triggered by minor trauma face, genitals, GI tract, extremities, and resp tract most commonly involved C2 and C4 also low Dx: measure the C1 esterase inhibitor

Question 34

What are the warning signs for an immunodeficiency?

Answer 34

1. 4 or more new ear infections within 1 year 2. two or more series sinus infections within 1 year 3. 2 or more months on antibiotics with little effect 4. 2 or more pneumonias within 1 year 5. failure of an infant to gain weight or grow normally 6. recurrent deep skin or organ abscesses 7. persistent thrush or fungal infections in mouth or elsewhere on skin 8. need for IV antibiotics to clear infections 9. two or more deep-seated infections including septicaemia 10. A family history of primary immunodeficiency if someone has 1- 2 or more of these signs, should consider.

Question 35

Which primary immune deficiencies that affect lymphocytes are typically associated with neutropenia?

Answer 35

1. X linked agammaglobulinemia 2. hyper IgM syndrome 3. severe T cell defecs/rare NK cell deficiencies

Question 36

Name 4 diseases associated with early complement deficiencies (C1-C4, factor I and H)

Answer 36

autoimmune diseases ie 1. glomerulonetphritis 2. SLE 3. dermatomyositis 4. scleroderma 5. vasculitis 6. infections with encapsulated organisms

Question 37

Describe disease associated with late complement deficiency (C5-C9)

Answer 37

recurrent neisserial diseases all the complement deficiencies can be inherited C2 and C4 most common

Question 38

What triggers are associated with hereditary C1 inhibitor deficiency

Answer 38

causes hereditary angioedema trieggers include: infections, OCP, pregnancy, minor trauma, stress autosomal dominant condition (failure to inactivate complement and kynin)

Question 39

Symptoms of C1 inhibitor deficiency

Answer 39

recurrent facial and extremity swelling abdominal pain hoarseness/stridor

Question 40

Which laboratory tests appropriately evaluate the phagocytic system?

Answer 40

1. Absolute granulocyte count Antineutrophil antibodies (although only found in half the cases of autoimmune neutropenia of infancy); bone marrow biopsy 2. Specific Assays include: a) determination of chemotaxis (not routinely used) b) quantification of nutrophile adherence - measure the expression of leukocyte function antigen-1 by flow cytometry c) Determination of respiratory burst: - nitroblue tetrazolium test - not used much anymore - ***dihydrorhodamine (DHR) 123 test - in activated granulocytes reactive oxygen intermediates reduce DHR 123 to rhodamine 123 (increased fluorescence on flow cytometry) d) enzyme assays e) treatment with rHu GCSF - autoimmune neutropenia should respond fairly quickly, congenital forms take longer and larger doses f) mutational analysis

Question 41

What are the main disorders of defective phagocytosis

Answer 41

Defective phagocytosis (10% of primary immunodeficiency). Main ones to know 1. chronic granulomatous disease 2. hyper IgE (Job) 3. Chediak Higashi 4. Leukocyte Adhesion Deficiency 5. Schwachmann Diamond 6. Kostmann syndrome

Question 42

6 week old baby with erythema and induration around his umbilical cord which is still firmly attached. What underlying condition should you suspect?

Answer 42

Leukocyte Adhesion Deficiency Zitelli – rare but most commonly from deficiency in CD18 (needed for neutrophils to exit blood vessels and enter tissue). range of disease from mild to severe. Symptoms include delayed umbilical cord separation, persisten and dramatic peripheral blood granulocytosis (ie increased neutrophil), recurrent soft tissue infections and impaired wound healing Will not form pus Should suspect in any baby with periumbilical problems and persistent peripheral blood leukocytosis **however, most babies with delayed separation of umbilicus will not have LAD (since it is rare) normal umbilicus: separates by 10 days on average, normal from 3-45 days (secretes)

Question 43

What are the pathological findings in LAD?

Answer 43

1. persistent neutrophil leukocytosis 2. lack of neutrophils at sites of infection (necrotic areas without pus) 3. severe lymphocyte deplesion in lymphoid tissues 4. impaired wound healing labs: flow cytometry - detect CD11/18 antigens on WBCs (should be low in LAD)

Question 44

What are the manifestations of severe disease from LAD in newborn?

Answer 44

delayed separation of the umbilical cord (normal average 10 days, between 3-45 days normal) omphalitis persistent leukocytosis (>50 000 cells/mm3 often) in newborn period high neutrophils but they can't get there they need to go severe disease: usually die before 2 years of age Treatment: bone marrow transplantation

Question 45

What are the manifestations of severe disease from LAD in childhood after infancy?

Answer 45

severe sinusitis destructive periodontis recurrent infections with : S. aureus, gram-negative enteric bacteria, also with fungi

Question 46

What is the molecular defect in chronic granulomatous disease?

Answer 46

profound defect in the oxygen metabolic burst in the myeloid cells following phagocytosis of microbes therefore, they lack superoxide oxygen radicals and peroxide ->cannot kill catalase-positive bacteria and fungi

Question 47

Name 5 organisms that people with CGD are especially vulnerable too

Answer 47

``` catalase positive bacteria and fungi, 5 main organisms: 1. S. aureus 2. Burkholderia cepacia 3. Serratia marcescens 4. Aspergillus 5. Nocardia 6. salmonella (gram negative catalase psotivie - e. coli, klebsiella, enterobacter, salmonella) **not sure if all of these are the most common, salmonella is for sure candida ```

Question 48

What lab test should you do to diagnose CGD?

Answer 48

flow cytometric DHR 123 test ***dihydrorhodamine (DHR) 123 test - in activated granulocytes reactive oxygen intermediates reduce DHR 123 to rhodamine 123 (increased fluorescence on flow cytometry) old test: nitroblue tetrazolium reduction test

Question 49

A 3 year old child presents with a liver abscess. He previously had multiple episodes of pneumonia and a "bone infection". What condition must you rule out?

Answer 49

chronic granulomatous disease a male child with liver abscess (in the absence of known immunosuppression) should be considered to have chronic granulomatous disease until proven otherwise

Question 50

What other infections might you see in the child above?

Answer 50

1. skin - superficial staph skin infections (nose, eyes, anus) 2. lymph nodes - severe adenitis 3. lungs - recurrent pneumonia 4. liver - liver abscess as mentioned hepatomegaly is common -likely from involvement of th ereticuloendothelial system can get granulomas elsewhere also (i.e. in the gastric antrum) can also have indolent osteomyelitis and chronic diarrhea

Question 51

How do you treat CGD?

Answer 51

1. prevent infection - immunization, prophylactive antibiotic and anti-aspergillus, avoid pathogens i.e.: septa and itraconazole 2. prophylactic interferon gamma (controversial) 3. early and aggressive use of parenteral antibiotics 4. surgery for infections

Question 52

A child presents with recurrent staph skin infections, coarse facial features and staph pneumonia . What condition do you suspect?

Answer 52

hyper IgE syndrome (autosomal recessive or dominant) (listed as either phagocytic disorder or combined ID depending on where you look) Clinical presentation: 1. recurrent staph infections - skin: ie impetigo and furuncles , hard to treat - lungs: pneumonia with abscess/pneumoatocele 2. pruritic eczematous dermatitis 3. coasrse facial features Autosomal dominant form only has bone stuff: - recurrent fractures and increased risk of osteomyelitis - delayed eruption of secondary teeth get "cold boils" no pain, heat or redness

Question 53

What lab results would you expect in hyper IgE (Job) syndrome?

Answer 53

increased IgE >2000 IU/mL (aka 20 000) eosinophilia abnormal cell-mediated immunity abnormal PMN chemotaxis (on neutrophil chemotaxis assay) autosomal dominant mutations in STAT3 or AR recessive mutation sin Dock 8 Management: treat infections, anti-staph prophylaxis

Question 54

Treatment for hyper IgE (Job) syndrome

Answer 54

e: anti staphylococcal antibiotic coverage (Oski, look elsewhere too)

Question 55

A child presents with poor growth, severe and recurrent infections, chondrodysplasia , steatorrhea , what condition do you suspect?

Answer 55

Schwachman-Bodian-Diamond syndrome: severe neutropenia and neutrophil chemotaxis abnormalities, autosomal recessive Diagnosis: neutropenia, genetic testing for 7q11 (**might also think of SCID depending on age/presentation, bone stuff different in the two)

Question 56

Treatment for Schwachman-Bodian-Diamond syndrome

Answer 56

pancreatic enzyme replacement | targeted antibiotic therapy

Question 57

What are the features of Chediak Higashi syndrome

Answer 57

imparied NK cell function, neutrophil chemotaxis and phagocytosis 1. recurrent skin and resp infections 2. severe gingivitis and periodontal disease 3. oculocutaneous albinism 4. easy bruising 5. almost all develop a lymphoma-like illness by age 10 which is typically fatal Diagnosis: giant granules in neutrophils, esosinophil and granulocytes variable amount of neutropenia and thrombocytopenia Treatment: bone marrow transplantation

Question 58

What is Kostman syndrome?

Answer 58

severe congenital neutropenia autosomal recessive severe infections starting in infancy, mortabiliy is 70% in the first hear of life (withou treatment) severe neutropenia (ANC<200) Treatment: GCSF, bone marrow or stem cell transplantation

Question 59

What is the allergic march

Answer 59

typical sequence of IgE development | food allergies->ezcema (late infancy) - >asthma (early childhood)->allergic rhinitis

Question 60

What are major and minor determinants against penicillin?

Answer 60

Pre-pen is a major determinant - benzyl penicillin absolutely penicillin allergic major determinant - identifies a true anaphylactic reaction identifies 90% of pen allergic patient minor determinant - another type of penicillin -

Question 61

You suspect a 6 year old of having a T-cell defect. The best screen is:

Answer 61

Candida skin test is the most cost effective way to screen for T cell defects also in secrets - read this Secrets: skin tests for assessment of delayed-type hypersensitivity are difficult to evaluate. positive test is useful for eliminating the diagnosis of severe T cell deficiency

Question 62

true or false - steroids usually affect results of skin test

Answer 62

false - they usually don't (but can)

Question 63

What is the most common immunodeficiency syndrome?

Answer 63

IgA deficiency | t reach adult levels until that age

Question 64

Diseases associated with increased IgE:

Answer 64

``` Immunodeficiency hyper igE igA deficiency nezelof DiGeorge Wiscott-Aldrich kawasaki table 135-2 in nelson ```

Question 65

What are the immunoglobulins in wiscott-aldrich

Answer 65

increased igA and IgE decreased IgM (KEY) variable IgG also have eczema and small platelets

Question 66

Diagnosis of ataxia telangiectasia

Answer 66

Low IgA, low IgG2, elevated AFP, definite testing is sequencing ATM gene (breakage in chromosomes 7 and 14)

Question 67

Triad with ataxia telangiectasia

Answer 67

telangiectasis not present at birth progressive ataxia - wheelchair bound by teens B and T cell deficiency

Question 68

Inheritance of hereditary angioedema

Answer 68

autosomal dominant

Question 69

Deficiency

Answer 69

C1 esterase inhibitor deficiency | activated complement system, cannot inactivate itself

Question 70

Clinical features of hereditary angioedema

Answer 70

clinical presentation: - non pitting edema, self-resolves within 3 days - no associated pruritus, no signs of anaphylaxis, no pain anywhere, can get some abdominal pain (edema of the bowel)

Question 71

triggers of hereditary angioedema

Answer 71

stress, OCP, pregnancies, periods, infections

Question 72

if they have a attack

Answer 72

give concentrated C1 inhibitor esterase and can give danazol (synthetic androgen) epi/steroids etc doesn't work

Question 73

which immunodeficiency - bad reactions to live vaccines

Answer 73

SCID low lymphocytes at birth **read about SCID

Question 74

Treatment of chronic urticaria

Answer 74

start with H1 anti-histamine - cetirizine then add H2 then try steroids on alternating days

Question 75

What are the lab tests in ataxia telangiectasia?

Answer 75

blood count - lymphopenia, increased eosinophils reduced IgA, TgG and IgE poor polysaccharide response increased autoantibodies (inducing to IgA and IgG) T cell immunity is abnormal in about 60% of patients

Question 76

What are the clinical features of SCID?

Answer 76

Secrets: 1. recurrent bacterial infections (pneumonia, OM, sepsis) 2. persistent viral infections 3. opportunistic infections (PCP, pneumocystic jiroveci, fungi) 4. failure to thrive 5. diarrhea (entero, rotavirus) may include skin rash

Question 77

Main lab test for SCID?

Answer 77

CBC - to document lymphopenia (<2000/mm3) | the single most test in the initial evaluation

Question 78

How many patients with SCID will have a normal lymphocyte count

Answer 78

about 20%

Question 79

What are the four most common form of SCID

Answer 79

X linked - 50% JAK3 deficiency - 10% IL-7 receptor deficiency - 10% ADA deficiency - 8%

Question 80

What are the clinical phenotypes of adenosine deaminase deficiency

Answer 80

1. neonatal or infantile onset - 80-90% - lymphopenia, no hum oral or cellulr immune functions - FTT - severe infections with fungi, viral and opportunist pathogens * *half of them have flare ribs - abnormalities at the costochondral junction 2. Delayed onset - 15-20% - recurrent infections - (sinopulmonary, sepsis, can't generate specific antibodies) - increased IgE levels, IgG subclass deficiency and autoimmunity

Question 81

What diagnosis should you consider in a 3 month old infant with type 1 diabetes, severe diarrhea and eczema

Answer 81

IPEX aka Immunodysregulation: severe colitis with cytopenias Polyendocrinopathy: can get neonatal insulin dependent diabetes Enteropathy X-linked : males in the first/2nd year of life caused by deficiency in the fork-head DNA binding protein FOXP3 Tx: immune suppression and bone marrow transplant

Question 82

Labs in the diagnosis above

Answer 82

increased eosinophils increased IgE and IgA but usually normal T and B cells severe diarrhea and FTT other autoimmune features - DM1, hypothyroidism, hemolytic anemia

Question 83

What is APS1 syndrome

Answer 83

primary immune deficiency with autoimmunity features include: 1. chronic mucocutaneous candidiasis (<15 years old)

Question 84

What is autoimmune lymphoproliferative syndrome?

Answer 84

autoimmune features in 70% of patients - include ITP, autoimmune hemolytic anemia, ITP, autoimmune neutropenia caused by different gene defects- lead to failure of apoptosis0

Question 85

Which primary immunodeficiencies are mitochrondiopathie?

Answer 85

mitochondria in charge of apoptosis 1. Reticular dysgenesis - a rare form (AR) of SCID 2. Kostman disease - severe congenital neutropenia

Question 86

What should be your initial screening tests for a suspected immunodeficiency (obviously depends on the case)

Answer 86

CBC (Hg morphology, absolute cellularity), Ig levels, antibody responses to previous antigen exposures (i.e. vaccines, pathogen), determination of isohemagglutinin titers assess complement pathway - CH50 work up of infections (i.e. CRP, cultures, X ray etc) no need for blanket screening - only if it will affect the management of the patient

Question 87

You suspect a humoural immune system problem. Which tests will be most helpful.

Answer 87

1. serum Ig Levels - comgined IgG, IgA, IgM level5000IU/mL for IgE - suggests hyper IgE syndrome 2. IgG sublasses - if >6 years old in certain circumstances or if recurrent sinopulmonary infections 3. specific antibody tigers 4. isohemagglutinin titer 1:4 or less after age 1 years suggests specific IgM deficiency 5. tetanus, diphtherai IgG1 6. pneumococcal polysaccharide antigens - IgG2 7. viral respiratory agents IgG3 8. B cell numbers - flow cytometry CD19, CD20 9. B cell proliferation and Ig production - in vitro assays

Question 88

Which tests help evaluate T cell functions

Answer 88

1. total lymphocyte count (although most T cell immune deficiencies normal) <60% mononuclear cells 3. delayed type hypersensitivity skin testing 4. proliferative response 5. acquisition of activation markers on T cells (using flow cytometry) 6. cytotoxic assay 7. cytokine synthesis 8. aADA and purine nucleoside phosphorylase in RBCs 9. molecular biology studies 10. Histology of thymic and lymph-node biopsies

Question 89

What is the value of skin testing for the diagnosis of T cell deficiencies?

Answer 89

positive test - helps eliminate diagnosis of severe T cell deficiency Negative test -- may reflect a T cell defect - may result from lack of a response to the antigens used Candida skin test: 75% of normal children will respond at 12-36 months, 90% by 18 months

Question 90

What is the cause of decreased CD4/CD8 ratio?of increased ratio?

Answer 90

decreased - think of HIV and other viral infections | increased - bacterial infections

Question 91

Which lab tests to evaluate the phagocytic system

Answer 91

Absolute granulocyte count - antineutrophil antibodies - bone marrow biopsy Specific assays: 1. determination of chemotaxis (not routine) 2. quantification of nutrophil adherence - CD11/CD18 by flow cytometry 3. respiratory burst - NBT test ; DHR 123 test for CGD 4. enzyme assays 5. treatment with GSCF 6. mutational analysis

Question 92

How to evaluate the classic complement cascade?

Answer 92

1. primary screening test- CH50: tests the individuals ability to lyse cells which are sensitized with rabbit IgM anti sheep antibody quantity of complement needed for 50% lysis of RBCs in a standardized setting relatively insensitive -need major changes before altered therefore, C3 and C4 are often also include in the initial screening of a child with a suspected complement deficiency

Question 93

What is an Arthus reaction

Answer 93

local reaction to an injected antigen type III large amounts of antigen leads to serum sickness- classic example of type III

Question 94

skin findings in atopy

Answer 94

baby nelson 1. hyper linearity of the plasm and soles 2. white dermatographism 3. pityriasis alba 4. creases under the lower eyelids (Dennie-Morgan folds or Dennie lines) 5. keratosis pilaris

Question 95

Diseases associated with elevated IgE

Answer 95

pg 272 baby Nelson 1. allergic disease 2. atopic dermatitis (eczema) 3. tissue invasive helminthic infections 4. hyperimmunoglobulin E syndromes 5. allergic bronchopulmonary aspergillosis 6. Wiskott-Aldrich syndrome 7. bone marrow transplant 8. Hodgkin disease 9. Bullous pemphigoid 10. Idiopathic nephrotic syndrome

Question 96

Diseases associated with eosinophilia

Answer 96

(when extreme eosinophilia, suggests non allergic - i.e. infections with tissue invasive parasites, drug reactions, or malignancies eosinophilia is 3-10% of WBC or absolute of >250 eosinophils/mm3 1. Allergic Disease: allergic rhinitis, atopic dermatitis, asthma 2. GI: allergic colitis, IBD, eosinophilic gastroenteritis 3. Infectious:: tissue-invasive helminthic infections 4. Neoplastic: eosinophilic leukemia, Hodgkin disease 5. Respiratory: eosinophilic pneumonia, allergic bronchopulmonary aspergillosis 6. Systemic: idiopathic hypereosinophilic syndrome, adrenal insufficiency, mastocytosis 7. Iatrogenic : drug induced

Question 97

true or false - the presence of IgE antibodies specific are enough to diagnose an allergy?

Answer 97

false - need to look at the whole picture - i.e. physician assessment and whole picture, correlate the findings but is a good option for those that can't do skin testing

Question 98

side effects of inhaled steroids for asthma

Answer 98

NOT side effects at low-medium doses: HPA function, glucose, cataracts or glaucoma DON't happen Local effects: dysphonia and candidiasis, absorption from GI tract

Question 99

systemic side effects of multiple courses of oral steroids

Answer 99

``` HPA suppression cushingoid features weight gain hypertension diabetes cataracts glaucoma osteoporosis growth suppression ```

Question 100

Treatment of rhinitis

Answer 100

intranasal corticosteroids - most postnet pharmacological treatment side effects; local irritation, burning, sneezing (in 10%), nasal bleeding can happen (if spray the septum) rare cases of nasal septum perforation

Question 101

What are the two generations of antihistamines, and which are less sedating?

Answer 101

1) first generation antihistamines - diphenhydramine and hydroxizine (i.e. addax) : cross the blood-brain barrier, quite sedating; can get paradoxical reaction in younger kids; can also get anticholinergic effects 2) second generation antihistamines: cetirizine, loratadine, desloratadine, fexofenadine, levocetirizine - less likely to cross site BBB, less sedation 3) topical nasal antihistamines - aka azelestine, olopatadine - for kids > 5-6 years

Question 102

How long should you limit use of nasal decongestant spray?

Answer 102

5-7 days to prevent rebound nasal congestion

Question 103

what percentage of kids with moderate to severe atopic dermatitis will have food allergies

Answer 103

35-40% will have food allergies | egg allergies is the most common cause of food-induced eczematous reactions

Question 104

medications that should be avoided by a person with anaphylaxis

Answer 104

beta blockers ACE inhibitors monoamine oxidase inhitors - d/c because they might worsen anaphylaxis or interfere with treatment

Question 105

labs in serum sickness

Answer 105

``` baby Nelson) increased ESR circulating immune complexes depressed complement - C3 and C4 levels skin biopsy might show immune deposits of IgM, IgA, IgE or C3 hematuria or proteinuria or both ```