Hypersensitivity Disorders Flashcards
Name some protective factors for allergic rhinitis
rural upbringing with early life exposure to farm animals, day care attendance, large family size, exposure to pets, number of siblings
When does the late phase allergic response begin and how long does it last ?
4-8 hours; 24 hours
What is typical of FeNo in allergic rhinitis and sinusitis, respectively?
high, low
What is the term used to describe the effect by which progressively lower doses of allergen are needed to trigger subsequent symptoms?
priming
What symptom is prominent in the late phase response of allergic rhinitis?
congestion
What is the most effective medication for allergic rhinitis?
nasal steroids
How is nonallergic rhinitis with eosinophilia (NARES) different from allergic rhinitis?
no elevated total or specific IgE
Nasal crusting is characteristic of what kind of rhinitis?
atrophic
Hormone induced rhinitis may be associated with what endocrine disorder?
hypothyroid - TSH stimulates edema in turbinates
What are the common pathogens that cause bacterial acute rhinosinusitis?
strep pneumo, moraxella catarrhalis, haemophilus influenzae
What is a Haller cell?
A pneumatized ethmoid cell that blocks the ostiomeatal complex
Where do nasal polyps typically originate?
ethmoid sinuses
Which mediators are increased in CRS without nasal polyps?
IL-3, PGE2
Which mediators are increased in CRS with nasal polyps?
IL-5, Eotaxin, LCTC4/D4/E4
Conjunctivitis with otitis is more likely caused by what organism?
H. influenzae
How is recurrent otitis media defined?
> 3 episodes within 6 months or >4/yr
What is the leading cause of hearing loss in children?
otitis media with effusion (non-infectious)
What is a destructive, expanding accumulation of keratinized squamous epithelium in the middle ear or mastoid?
cholesteatoma
Papillary hypertrophy, thick ropey ocular discharge, and Horner-Trantas dots are characteristic of what?
Vernal keratoconjuctivitis
Where do cataracts arise due to steroid administration?
posterior capsule
What is the greatest risk factor for giant papillary conjunctivitis?
contact lens use
A decrease in what antimicrobial peptides increase the risk of infection in atopic dermatitis?
defensins, cathelicidin
What are the cytokines involved in acute and chronic atopic dermatitis, respectively?
IL-4, IL-13; IL-5, IL-12, IFNγ
Polymorphisms in which TLR is linked to severe atopic dermatitis with frequent bacterial infections?
TLR2
Loss of function mutations in what predisposes to development of atopic dermatitis?
filaggrin
What is the ligand for E selectin that helps T cells home to the skin in atopic dermatitis?
cutaneous lymphocte-associated antigen (CLA)
The presence of Birbeck granules are characteristic of what cell type?
Langerhans cells
Which cytokine is primarily associated with pruritis in atopic dermatitis?
IL-31
Where are cataracts due to atopic keratoconjunctivitis found?
anterior capsule
Deficiency of which antimicrobial peptide in atopic skin may contribute to eczema vaccinatum?
cathelicidin (LL-37)
A 3 y/o boy presents with bloody stools, ear drainage and eczema. What PID should be considered?
Wiscott-Aldrich syndrome
Vitamin D induces production of which antimicrobial peptide in atopic individuals?
cathelicidin (LL-37)
Accumulation of what cell type is associated with fatal asthma?
neutrophils
Hyperplasia of submucosal glands in asthma is promoted by which cytokine?
IL-9
Sensitization to what by age 6 is associated with persistence of asthma at age 11?
alternaria
A 5q31-33 polymorphism can contribute to atopic asthma by increasing production of which interleukin ?
IL-4
A β2-adrenoreceptor gene can lead to what?
decreased response to β2 agonist
What is the most frequent infections cause of asthma exacerbations?
rhinovirus
What is the asthma predictive index?
Major criteria (1 needed): parental asthma, dx of eczema, allergic sensitization Minor criteria (2 needed): sensitization to foods, eosinophilia, wheezing apart from colds
Classify the asthma severity of a 3 y/o with daily symptoms, 3 nighttime awakenings/month, and daily SABA use. What initial step therapy should be used?
moderate persistent, step 3
Classify the asthma severity of a 8 y/o with symptoms/SABA use 4 days/week, 3 nighttime awakenings/month, and an FEV1 of 83%. What initial step therapy should be used?
mild persistent, step 2
Classify the asthma severity of a 8 y/o with symptoms/SABA use 4 days/week, weekly nighttime awakenings, and an FEV1 of 76%. What initial step therapy should be used?
moderate persistent; step 3
Classify the asthma severity of a 13 y/o with symptoms/SABA use 4 days/week, 3 nighttime awakenings/month, and an FEV1 of 83%. What initial step therapy should be used?
mild persistent, step 2
What initial step of therapy should be used for an 8 y/o with severe persistent asthma?
step 3-4
What initial step of therapy should be used for an 15 y/o with severe persistent asthma?
Step 4-5
Classify the asthma severity of a 3 y/o with daily symptoms, weekly nighttime awakenings, and SABA use several times per day. What initial step therapy should be used?
severe persistent; step 4
Classify the asthma severity of a 3 y/o with symptoms/SABA use 4 days/week, nighttime awakenings twice/month. What initial step therapy should be used?
mild persistent; step 2
Classify the asthma severity of an infant with 3 exacerbations in the last 6 months who’s mother has asthma. No symptoms outside of exacerbations. What initial step therapy should be used?
mild persistent; step 2
Classify the asthma severity of a 23 y/o with 3 exacerbations/year and an FEV1 of 65%. What initial step therapy should be used?
moderate persistent; step 3
Assess the asthma control in a 2 y/o with symptoms 3 days/week with 1 nocturnal awakening/month and 2 exacerbations/year. What action should be taken?
not well controlled; step up 1 step
Assess the asthma control in a 10 y/o with symptoms 2 days/week with 1 nocturnal awakening/month and 1 exacerbation/year. What action should be taken?
controlled, no action
Assess the asthma control in a 14 y/o with symptoms throughout the day, 5 nocturnal awakenings/month, an FEV1 of 58% and 2 exacerbations/year. What action should be taken?
very poorly controlled; step up 1-2 steps and consider oral steroids
Assess the asthma control in a 2 y/o with daily symptoms, 5 nocturnal awakenings/month and 4 exacerbations/year. What action should be taken?
very poorly controlled; step up 1-2 steps, consider oral steroids
Assess the asthma control in a 10 y/o with symptoms 3 days/week with 2 nocturnal awakenings/month, and FEV1 of 78%, and 2 exacerbations/year. What action should be taken?
not well controlled; step up 1 step
Assess the asthma control in a 14 y/o with symptoms 5 days/week, 3 nocturnal awakenings/month, an FEV1 of 62% and 2 exacerbations/year. What action should be taken?
Not well controlled; step up one step
What is step 1 therapy for children ages 0-4?
SABA PRN
What is step 1 therapy for children ages 5-11?
SABA PRN
What is step 1 therapy for adults?
SABA PRN
What is step 2 therapy for children ages 0-4?
low dose ICS; alternative = montelukast or cromolyn
What is step 2 therapy for children ages 5-11?
low dose ICS; alternative = montelukast, theophylline or cromolyn
What is step 2 therapy for adults?
low dose ICS; alternative = montelukast, nedocromil, theophylline or cromolyn
What is step 3 therapy for children ages 0-4?
medium dose ICS
What is step 3 therapy for children ages 5-11?
low dose ICS + LABA or LTRA or theophylline; alternative = medium dose ICS
What is step 3 therapy for adults?
low dose ICS + LABA or LTRA or theophylline or zileuton; alternative = medium dose ICS
What is step 4 therapy for children ages 0-4?
medium dose ICS + LABA or LTRA
What is step 4 therapy for children ages 5-11?
medium dose ICS + LABA or LTRA or theophylline
What is step 4 therapy for adults?
medium dose ICS + LABA or LTRA or theophylline or zileuton
What is step 5 therapy for adults?
high dose ICS + LABA and consider omalizumab
What is step 5 therapy for children ages 5-11?
high dose ICS + LABA or LTRA or theophylline
What is step 5 therapy for children ages 0-4?
high dose ICS + LABA or LTRA
What is step 6 therapy for children ages 0-4?
high dose ICS + LABA or LTRA + oral corticosteroids
What is step 6 therapy for children ages 5-11?
high dose ICS + LABA or LTRA or theophylline + oral steroids
What is step 6 therapy for adults?
high dose ICS + LABA + oral steroids and consider omalizumab
What agents are the most common causes of occupational asthma?
latex, wheat, isocyanates, plicatic acid
Smoking is a risk factor for sensitization to what?
Platinum
β-1,3-glucan in fungal cell walls binds to what on macrophages?
dectin-1; important in ABPA
What serological marker can indicate an exacerbation of ABPA?
IgE doubles
What are the diagnostic criteria for allergic fungal sinusitis?
sensitization to fungi
nasal polyps
positive fungal stain of sinus contents
histology showing eosinophils, fungal elements
What are the CT findings in acute, subacute, and chronic hypersensitivity pneumonitis?
acute - normal or fleeting ground glass opacities
subacute - diffuse micronodules, air trapping, mild fibrosis
Chronic - ground glass, emphysema, honeycombing, micronodules
What antigen is implicated in farmer’s lung (hypersensitivity pneumonitis)?
mold
What antigen is implicated in hot tub lung (hypersensitivity pneumonitis)?
mycobacterium avium
What antigen is implicated in bird fancier’s lung (hypersensitivity pneumonitis)?
aspergillus and avian proteins
What antigen is implicated in air conditioner lung (hypersensitivity pneumonitis)?
aureobasidium
What are the diagnostic criteria for hypersensitivity pneumonitis?
HP symptoms Evidence of exposure (history and +IgG) Radiographic evidence BAL showing >20% lymphocytes (low CD4:CD8 ratio) symptoms on re-exposure
What is seen on biopsy in hypersensitivity pneumonitis?
noncaseating granulomas
lymphocytes
foamy histiocytes in alvioli
giant cells
What PFT findings are seen after exposure in hypersensitivity pneumonitis?
drop in FEV1, FVC and DLCO 4-6 hrs after exposure
What is the non-infectious febrile illness that occurs in workers after exposure to dust contaminated with toxin producing bacterial and/or fungal spores?
organic dust toxic syndrome (ODTS)
- 30-50 x more common than hypersensitivity pneumonitis
What causes symptoms in silo unloaders disease?
acute exposure to NO2 leading to asphyxia
What causes symptoms in byssinosis?
dust inhalation of cotton, flax and hemp
What causes symptoms in humidifier fever?
toxic alveolitis due to endotoxin in recirculated water
What is the most common form of hypersensitivity pneumonitis?
farmer’s lung - but more common is organic dust toxic syndrome which can occur after only one exposure
What is seen on PFTs in idiopathic pulmonary fibrosis (usual interstitial pneumonitis)?
restrictive pattern with reduced DLCO
What is seen on CT in idiopathic pulmonary fibrosis (usual interstitial pneumonitis)?
honeycombing, diffuse interstitial infiltrates
What are the GOLD criteria for grading severity of COPD?
GOLD 1: mild - FEV1 > 80%
GOLD 2: moderate - FEV1 50 - 80%
GOLD 3: severe - FEV1 30 - 50%
GOLD 4: FEV1
Which cell types are prominent in the airway in COPD?
neutrophils and macrophages
Sputum eosinophils are a marker of what in COPD?
viral exacerbation
Centrilobular emphysema seen in COPD is associated with what?
smoking
Panlobular emphysema seen in COPD is associated with what?
α1-antitrypsin deficiency
What is the only treatment that prolongs life in COPD?
O2 supplementation
A 39 y/o man eats tuna and within 20 minutes develops abdominal cramps, vomiting, swelling of the tongue and SOB. He has no hx of fish allergy and SPT is negative. What is the Dx?
scromboid poisoning - contaminated fish, resembles allergic reaction
How does sensitization take place in Class 1 and 2 allergens, respectively?
through the skin (foods); through the respiratory system (pollens with epitopes similar to food epitopes)
What is the difference between conformational and linear epitopes?
conformational epitopes allergenicity is dependent upon the folding into the 3D structure, linear are not
Name the antigen in birch and in apples/peaches that cross react.
Bet v 1 (birch), Mal d 1 (apple,peach)
What syndrome is characterized by recurrent pneumonia, pulm infiltrates, hemosiderosis, Fe def. anemia, failure to thrive, eosinophilia, and milk precipitins?
Heiner’s syndrome
What does dermatitis herpetiformis look like and what is it associated with?
vesicular, pruritic lesions on sun exposed areas; celiac disease
In galactose-α-1,3-galactose hypersensitivity, how soon after ingestion do symptoms begin?
3-6 hours
What type of allergen is galactose-α-1,3-galactose, and what chemotherapeutic mAb does it react with?
carbohydrate part of a glycoprotein; cetuximab
Which peanut component is associated with systemic reactions?
Ara h 2
Which peanut component is associated with oral reactions?
Ara h 8
What are the most common causes of anaphylaxis?
food and drug reactions
How can chymase act to improve symptoms of anaphylaxis?
Can convert angiotensin I to II - improves BP
What are the diagnostic criteria for anaphylaxis?
hives and/or angioedema with at least 1 of:
respiratory sx, drop in BP or end organ dysfunction
What % of anaphylactic episodes experience a biphasic or late phase reaction?
20%
What medications can modify the effects of anaphylaxis?
Beta blockers, ACEI, MAOIs (prevent degradation of epi)
* tricyclics exaggerate the response to epi
How can you differentiate anaphylaxis from mastocytosis?
look at total tryptase and mature tryptase - mature tryptase is released in anaphylaxis
mastocytosis total/mature tryptase is >20
When should serum histamine be checked when evaluating possible anaphylaxis?
15-60 minutes - levels rise in 5 minutes but only remain elevated for 30-60 minutes
For how long does urinary histamine remain elevated after anaphylaxis?
24 hours
When does serum tryptase peak after anaphylaxis?
60-90 minutes - can remain elevated for up to 5 hours
Besides histamine and tryptase, what other serological marker is elevated in anaphylaxis?
platelet-activating factor
Which allergenic component is common to those with spina bifida?
latex - Hev b 1 and 3
Which latex component is common for health care worker reactions?
Hev b 5, 6, and 7
Which allergen cross reacts with bell pepper, kiwi, potato, avocado, and chestnut?
latex
Which foods are the most commonly implicated in food dependent exercise induced anaphylaxis?
celery and wheat
What is the major honeybee allergen?
Phospholipase A
What is the major vespid allergen?
hyaluronidase
If severe hypotension occurs after a hymenoptera sting, what key blood test should be ordered?
tryptase
Which biting insect is the most common cause of systemic reactions?
Triatoma (kissing bug) - bites are painless
What is a Type II hypersensitivity reaction?
antibody dependent cytotoxic reaction
What is a type III hypersensitivity reaction?
Immune complex reaction
What is a type IV hypersensitivity reaction?
cell mediated or delayed type
In a type IVa hypersensitivity reaction, what cytokines are prominent, cell types involved and clinical manifestations?
IFNγ; monocytes; eczema
In a type IVb hypersensitivity reaction, what cytokines are prominent, cell types involved and clinical manifestations?
IL-4 and IL-5; eosinophils; maculopapular or bullous rxn
In a type IVc hypersensitivity reaction, what cytokines are prominent, cell types involved and clinical manifestations?
perforin and granzyme; CD4 and CD8 T cells; maculopapular or bullous rxn
In a type IVd hypersensitivity reaction, what cytokines are prominent, cell types involved and clinical manifestations?
IL-8; neutrophils; pustular rxn
HLA-B*5701 is strongly associated with reactions to which drug?
abacavir
HLA-DR3 is associated with reactions to which medications?
insulin, penicillamine and gold
What is in the Pre-Pen (major determinants)?
benzylpenicilloyl polylysine
What is in the minor determinants for PCN testing?
PCN G
Which medication cross reacts with ceftaZidime?
aZtrionam
80% of people taking augmentin will have a skin reaction if infected with what?
EBV
HIV patients will very commonly have a type IV reaction to which medication?
Bactrim
Type I hypersensitivity reactions to Bactrim are due to what?
N4 sulfonamidoyl hapten
What is the mechanism in radiocontrast reactions?
direct mast cell stimulation
Which medications are common causes of SJS and TEN?
PCN, sulfonamides, antconvulsants, NSAIDS, allopurinol
Which medications are common to DRESS?
anticonvulsants, sulfonamides, allopurinol, minocycline
What are the symptoms of dress?
fever, lymphadenopathy, hepatitis, facial edema weeks after therapy
Perioperative reactions are commonly due to which agents?
quaternary ammonium muscle relaxants (succinylcholine)
Fever, rash, bronchospasm, capillary leak syndrome, meningoencephalopathy, and elevated LFTs after rituximab (anti-CD20) is likely what Dx?
cytokine release syndrome
also due to muromonab (anti-CD3)
Which autoantibody is associated with drug induced cutaneous lupus?
anti-Ro (SSA)
Which autoantibody is associated with drug induced systemic lupus?
antihistone
How is acute urticaria defined?
less than 6 weeks
Which autoantibody is common in chronic idiopathic urticaria?
thyroid
How can you distinguish between cholinergic urticaria and exercise induced anaphylaxis?
EIA will not react with passive heating
What syndrome is characterized by urticaria with arthritis, obstructive lung disease, glomerulonephritis, uveitis, angioedema and recurrent abdominal pain? Also has low C3, C4, C1q, anti-C1q Ab and elevated ESR?
Hypocomplementemic urticarial vasculitis syndrome
How are patch tests graded?
Irritant
+/- = unlikely
+ = erythema and palpable edema
++ = microvesicles and erythema > 50% patch
+++ = confluent vesicldes or bullae, ulcerative
What is a common contact allergen for cement workers?
Chromates
What does the dimethylglyoxime test evaluate?
presence of nickel-containing material
What fruit can poison ivy/oak cross react with?
mango peels
What is the most common cause of eczema in flower workers?
peruvian lily
What is the common allergen in fragrances?
Balsam of Peru
What common allergen is a preservative found in fabrics?
Quaternium-15 (releases formaldehyde)
What is the most common contact allergen in hair dressers?
paraphenylenediamine
What is a common allergen in nail polishes?
ethylacrylate
What is the most common topical antibiotic causing contact dermatitis?
neomycin
What is systemic contact dermatitis?
the term used for generalized allergic contact dermatitis due to ingestion of an allergen
Which vaccines are live?
MMR nasal flu polio rotavirus smallpox shingles varicella
How far apart should live vaccines be separated if not given the same day?
28 days
What are the common allergic components in vaccines?
gelatin, egg, latex, yeast
What recommendations regarding an egg containing vaccine should be given to someone who has an egg allergy with hives only?
give vaccine and observe in PCP office for 30 minutes
What recommendations regarding an egg containing vaccine should be given to someone who has an egg allergy with anaphylaxis?
give vaccine and observe in allergist office and observe for 30 minutes
What are the contraindications to vaccinations?
previous anaphylaxis to vaccine
encephalopathy
What is the most common cause of bronchiolitis?
RSV
What is the monoclonal antibody against RSV and when should it be given?
Palivizumab - give monthly to high-risk infants youger than 2 yrs
What is the major cause of croup?
parainfluenza virus
What is the common radiographic sign seen in croup?
subglottic narrowing (steeple sign)
What are the time classifications for acute, subacute and chronic rhinosinusitis?
Less than 4 weeks, 4-8 weeks, 8-12 weeks
What must the particle size be to cause hypersensitivity pneumonitis?
less than 5 micrometers