Allergy and Asthma: Improving Outcomes in Primary Care
El Paso
November, 2007
Len Fromer, M.D., FAAFP
CHDs URDs
Treatment
CAP RAST
Perspectives
Summary
LRDs
The Etiology Challenge
• Common symptoms and diseases
have many possible etiologies
• IgE-mediated allergies trigger
symptoms from infancy into adulthood
• Identification of true underlying
cause is essential for effective
management
CHDs URDs
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CAP RAST
Perspectives
Summary
LRDs
The Allergic Inflammatory Response
CHDs URDs
Treatment
CAP RAST
Perspectives
Summary
LRDs
CHDs
Common Childhood Diseases
• The illnesses of the Allergy March
– Atopic dermatitis (eczema)
– GI distress
– Recurrent otitis media
– Allergic rhinitis
– Allergic asthma
• The symptoms
– Inflammatory in nature
– Multiple etiologies
– Treated empirically
CHDs URDs
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Summary
LRDs
The Allergy March: A Progression of Seemingly Unrelated Diseases
CHDs
Food
Sensitivity
Atopic
Dermatitis
GI
Distress
Recurrent
Otitis
Media
Allergic
Rhinitis
Allergic
Asthma
Genetic
Predisposition
Inhalant
Sensitivity
Time (~years)
CHDs URDs
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Perspectives
Summary
LRDs
CHDs
Allergy March
Prevalence of Atopic Disease
50
Prevalence (%)
40
30
20
10
0
1
3
5
10
17
Age (years)
Symptoms
Gastrointestinal
Respiratory
Skin
Saarinen UM, Kajosaari M. Lancet. 1995;346:1065-1069.
CHDs URDs
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CAP RAST
Perspectives
Summary
LRDs
CHDs
Allergy March
IgE Antibody Level
(Phadebas RAST Class)
Mean score
3
Birch pollen
2
Peanut
1
Egg white
n= 12
29
12
0
0-3
4-9
10 - 15
Age (years)
Sigurs N, et al. J Allergy Clin Immunol. 1994;94:757-763.
CHDs URDs
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Summary
LRDs
CHDs
Common Childhood Diseases
• Atopic dermatitis (AD)1
– 17%-20% prevalence in US, other western countries
– Not necessarily severe reaction (anaphylaxis)
– Driven by early exposure and sensitization
– 40% of AD caused by food sensitivity
– Empirical treatment: trials of topicals
1. Leung DYM. In: Pediatric Allergy: Principles and Practice. Mosby-Year Book, Inc; 2003:561-573.
CHDs URDs
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Summary
LRDs
CHDs
Common Childhood Diseases
• GI distress1
– Colic, diarrhea, vomiting, constipation, reflux
– Multiple etiologies:
• atopy, infection, intolerance, malabsorption, inflammatory bowel, anatomic defect
– 10%-42% of symptomatic patients are atopic2,3
– 50%-60% of infants with food sensitivities show GI symptoms
(not necessarily full-blown food allergy)
– Empirical treatment: trials of formulas
1. Høst A, Halken S. In: Pediatric Allergy: Principles and Practice. Mosby-Year Book, Inc; 2003:488-494.
2. Australasian Society of Clinical Immunology and Allergy. Adverse reactions to food. Available at:
http://www.allergy.org.au/aer/infobulletins/adverse_reactions.htm.
3. Sicherer SH. Pediatrics. 2003;111:1609-1616.
CHDs URDs
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Summary
LRDs
CHDs
Common Childhood Diseases
• Recurrent otitis media (OM)
– 26% prevalence in US1
– Key risk factors include attendance in daycare,
cigarette smoke exposure2
– 40%-50% involve atopy3,4
– Common underlying cause = eustachian tube dysfunction
• Caused by inflammation related to allergy or infection
• Recurrence = not treating the underlying cause
– Empirical treatment: antibiotics, surgery
1.
2.
3.
4.
Lanphear BP, et al. Pediatrics. 1997;99:1-7.
AAAAI. The Allergy Report. 2000;2:155-161.
Data on file, Pharmacia Diagnostics.
Fireman P. J Allergy Clin Immunol. 1997;99:S787-S797
CHDs URDs
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Summary
LRDs
Atopy’s Long-Term Consequences
CHDs
•
Nearly 80% of children with AD go on to develop allergic rhinitis and/or asthma1
•
Children with early and long-lasting food sensitization:
– 3x more likely to develop allergic rhinitis (AR) than those transiently sensitized2
– 5x more likely to develop asthma than those transiently sensitized2
•
Young wheezers with confirmed atopy are more likely to develop asthma3
1. Leung DYM. In: Pediatric Allergy: Principles and Practice. Mosby-Year Book, Inc; 2003:561-573.
2. Kulig M, et al. Pediatr Allergy Immunol. 1998;9:61-67.
3. Martinez FD, et al. J Allergy Clin Immunol 1999;104:S169-S174.
CHDs URDs
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Perspectives
Summary
LRDs
Knowledge of Etiology Guides Treatment for Today and Tomorrow
CHDs
• Specific IgE testing in children can help the clinician:
– Identify allergen sensitivities
– Counsel for avoidance
– Eliminate or reduce symptoms
– Reduce medication use (including antibiotics)
• Targeting atopy can eliminate symptoms and interrupt the Allergy March1-5
– ETAC: Cetirizine and avoidance halved asthma risk in children with AD1
– PAT: Immunotherapy significantly reduced asthma risk in children with AR2
– CCAPPS: Multifaceted avoidance intervention reduced asthma prevalence 56%
in high-risk children5
1.
2.
3.
4.
5.
ETAC® Study Group. Pediatr Allergy Immunol. 1998;9:116-124.
Möller C, et al. J Allergy Clin Immunol. 2002;109:251-256.
Platts-Mills TAE. N Engl J Med. 2003;349:207-208.
Sampson H. Ann Allergy Asthma Immunol. 2004;93:307-308.
Chan-Yeung M, et al. J Allergy Clin Immunol. 2005;116:49-55.
CHDs URDs
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LRDs
URDs
Etiology Is Elusive
CHDs URDs
Treatment
CAP RAST
Perspectives
Summary
LRDs
URDs
Overlapping Symptoms
Allergic Rhinitis
Non-allergic Rhinitis
Chronic Sinusitis
– Nasal congestion
– Nasal congestion
– Nasal congestion
– Rhinorrhea
– Rhinorrhea
– Rhinorrhea
– Increased
secretions
– Increased
secretions
– Increased
secretions
– Sneezing
– Postnasal drainage
– Postnasal drainage
– Itchy, watery eyes
– Headache
– Facial pain
CHDs URDs
Treatment
CAP RAST
Perspectives
Summary
LRDs
URDs
Upper Respiratory Diseases
• Allergic rhinitis, non-allergic rhinitis, sinusitis
• Symptoms caused by inflammation
– Multiple etiologies, including:
• Allergic
• Hormonal
• Anatomic
• Vasomotor
• Infectious
• Usually treated empirically/symptomatically
• Depending upon etiology, treatment can/should be different
CHDs URDs
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LRDs
Productivity Loss $ per 1000 Employees
$1,500,000
$1,436,292
$1,000,000
$880,152
$500,000
$520,884
$275,808
$0
Allergies
Respiratory
Depression
Diabetes
$187,200 $148,512
Hypertension
CV Disease
CHDs URDs
Treatment
CAP RAST
Perspectives
Summary
LRDs
Comparison of Quality-of-Life in Asthmatic & Chronic Rhinitis Patients
Mean Quality-of-Life Score (Scale 1-100)*
Asthma
Chronic Rhinitis
Health Concept
(n=252)
(n=111)
Social functioning
84
73
Physical functioning
89
80
Role limitations (emotional)
70
64
Role limitations (physical)
66
61
Energy/fatigue
59
55
Pain
74
77
Change in health (1 year)
55
50
CHDs URDs
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CAP RAST
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Summary
LRDs
URDs
Distribution of URD in US1-3
• 39% of total population (115M of 295M) have URD
Sinusitis
30%
35M
40M
Allergic Rhinitis
35%
40M
Non-allergic
Rhinitis
35%
1. AHRQ. Management of allergic and nonallergic rhinitis. May 2002: AHRQ Pub. No. 02-E023.
2. Spector SL, ed. Dialogues in Redefining Rhinitis. 1996;1(1,4):1-16.
3. Allergy Statistics.AAAAI Web site. Available at: http://www.aaaai.org/media/resources/media_kit/allergy_statistics.stm.
CHDs URDs
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Summary
LRDs
URDs
Actual Atopy and Antihistamine Use
Identification of allergic disease among users of antihistamines1
•
Allergic rhinitis, non-allergic rhinitis, sinusitis
•
Study of managed-care
patients repeatedly prescribed
oral antihistamines
•
Convenience sample
of 246 evaluated with
in vitro allergy testing
•
Results revealed non-atopic
symptom etiology in 2/3 of patients
35%
Atopic
Etiology
65%
Non-atopic
Etiology
1. Szeinbach SL, et al. J Manag Care Pharm. 2004;10(3):234-238.
CHDs URDs
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Summary
LRDs
URDs
Non-allergic Rhinitis
• Wide array of types and etiologies1,2
– Includes: infectious, vasomotor, hormonal, anatomic, occupational, drug-induced
• Not caused by IgE-mediated allergic inflammation
– Non-sedating antihistamines and other allergy-targeted therapies
will not treat underlying cause
1. AAAAI. The Allergy Report. 2000;2:1-31.
2. Dykewicz MS, et al. Ann Allergy Asthma Immunol. 1998;81:478-518.
CHDs URDs
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Summary
LRDs
URDs
Allergic Rhinitis
• Triggered by seasonal or perennial allergen(s)
• Symptoms may include:
– nasal congestion, rhinorrhea, increased secretions, sneezing,
itchy nose/eyes, watery eyes, coughing, postnasal drip1,2
• Cumulative threshold disease3,4:
– Patients are rarely monosensitized
– Symptoms emerge after “allergic threshold” has been exceeded
1. AAAAI. The Allergy Report. 2000;2:1-31.
2. Dykewicz MS, et al. Ann Allergy Asthma Immunol. 1998;81:478-518.
3. Pharmacia & Upjohn Diagnostics. The Value of Allergen Identification.1998. Publication 98006.01.
4. Wickman M. Allergy. 2005;60 (Suppl 79):14-18.
CHDs URDs
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Summary
LRDs
URDs
Cumulative Threshold Disease1
Symptoms
Ragweed
Dust mites
Cat dander
Situation A2
No avoidance
measures
Situation B3
No avoidance
measures
Third allergen
Situation C3
Avoidance measures
employed
Third allergen
1. Pharmacia & Upjohn Diagnostics. The Value of Allergen Identification. 1998. Publication 98006.01.
2. Ciprandi G, et al. J Allergy Clin Immunol. 1995;96:971-979.
3. Boner AL, et al. Clin Exp Allergy. 1993;23:1021-1026.
CHDs URDs
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Summary
LRDs
Support for Avoidance in the Management of Allergies and Asthma
URDs
URDs
• …It has become clear that early intervention may modulate the natural course of
atopic disease…the reduction in exposure of high-risk infants to food and housedust mite allergens substantially lowers the frequency of allergic manifestations
in infancy.”1 – Halmerbauer, et al.
• “Extensive experience suggests that both drug treatment and immunotherapy
are more effective if patients also decrease exposure. The approach is to identify
the allergen source (or sources) to which the patient is allergic and to educate
patients extensively.”2 – Platts-Mills, et al.
• The NIH, AAAAI, and AAFP urge trigger avoidance as a cornerstone
of asthma management3-5
1. Halmerbauer G, et al Pediatr Allergy Immunol. 2003;14:10-17.
2. Platts-Mills TAE, et al. J Allergy Clin Immunol. 2000;106(5)787-804 .
3. NIH. Guidelines for the Diagnosis and Management of Asthma.1997. NIH publication 97-4051.
4. AAAAI. The Allergy Report. 2000;2:33-109.
5. AAFP. Asthma & Allergy Resource Guide. 2004:11-13
Return to >> Cumulative Threshold
CHDs URDs
Treatment
CAP RAST
Perspectives
Summary
LRDs
URDs
Sinusitis
• Multiple etiologies
– Caused by inflammation from infection, allergy, structural abnormalities,
other causes1
– ENT experts use term “rhinosinusitis” due to epithelial continuum
of sinus/nasal passages1,2
• Common comorbidity–often with atopy
– Rarely occurs without concurrent rhinitis2
– >50% of moderate to severe asthmatics have chronic rhinosinusitis3
1. Brook I, et al. Ann Otol Rhinol Laryngol. 2000;109:2-20.
2. AAO-HNS. Fact sheet. ENT Link Web site. Available at: http://www.entnet.org/healthinfo/sinus/allergic_rhinitis.cfm.
3. AAAAI. The Allergy Report. 2000;2:7,137-153.
CHDs URDs
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Perspectives
Summary
LRDs
URDs
Why Should You Test?
•
History and physical alone yield a correct diagnosis only 50% of the time 1
•
Different etiologies demand different treatment approaches
•
Testing for specific IgE levels can rule in/out atopy
•
If atopic:
– NSAs probably drug of choice
– Testing can help clinician pinpoint offending allergens
•
If non-atopic:
– Results will allow you to focus on other etiologies
– Drugs of choice may include decongestants/steroids
– Patient can avoid unnecessary/ineffective treatment
1. Homburger HA. Arch Pathol Lab Med. 2004;128:1028-1031.
CHDs URDs
Treatment
CAP RAST
Perspectives
Summary
LRDs
URDs
URD Management Options
Specific IgE-Positive/Abnormal
Atopic Etiology
Specific IgE-Negative/Normal
Non-Atopic Etiology
Specific Allergen Avoidance
Inadequate Response
Allergy-Targeted
Pharmacotherapy
(eg, NSAs, LTRAs)
(allergy-targeted
Rx not helpful)
Response
Inadequate Response
Referral?
Pharmacotherapy
Adequate
Adequate
Response
Inadequate Response
Referral?
Stop
Stop
CHDs URDs
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Perspectives
Summary
LRDs
URDs
The Experts on Differential Diagnosis of Rhinitis
“A positive diagnosis (or diagnoses) should
be made before formulating management.”1
1. Middleton E, et al, eds. Allergy: Principles & Practice. Vol II, 5th ed. St. Louis, Mo: Mosley-Year Book, Inc; 1998:1007.
CHDs URDs
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LRDs
URDs
The Experts on Differential Diagnosis of Rhinitis
• An expert panel in the area of allergy diagnosis recommended selective use
of in vitro allergy testing by primary care physicians.
• According to these experts, in vitro tests1:
– Offer a well standardized alternative to skin testing
– Are easily used by generalist physicians
– Are effective in the diagnosis of allergy
1. Selner JC, et al. Ann Allergy Asthma Immunol. 1999;82:407-412.
CHDs URDs
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Summary
LRDs
URDs
The Experts on Differential Diagnosis of Rhinitis
“Allergy [IgE] testing should be considered in all patients
with a suspected diagnosis of allergic rhinitis.”1
1. Bierman CW, et al, eds. Allergy, Asthma, and Immunology From Infancy to Adulthood. 3rd ed. Philadelphia, Pa: WB Sanders Company; 1995:403-404.
CHDs URDs
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LRDs
LRDs
Etiology Linked to Triggers
CHDs URDs
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Summary
LRDs
LRDs
Overlapping Symptoms
“All that wheezes is not asthma.”
– Chevalier Jackson [1865-1958]
Allergic Asthma
Non-allergic Asthma
“Bronchitis”
– Wheezing
– Wheezing
– Wheezing
– Cough
– Cough
– Cough
– Dyspnea
– Dyspnea
– Dyspnea
– Chest tightness
– Chest tightness
– Rhinitis
– Conjunctivitis
CHDs URDs
Treatment
CAP RAST
Perspectives
Summary
LRDs
LRDs
Lower Respiratory Diseases
• Course and severity affected by inflammation (often caused by allergy)
• Underlying atopy shown to increase symptoms and precipitate exacerbations
• A wide range of possible triggers include:
– Allergy
– Occupational exposures
– Infection
– GERD
– Tobacco smoke
– Emotional stress
– Exercise
– Cold weather
CHDs URDs
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Summary
LRDs
LRDs
Asthma
• Widespread
– 7% prevalence (>20 million1) and rising
– 73% managed by PCPs2
• Allergic vs. non-allergic asthma
– 60% of asthmatics have allergic asthma3
– 90% of children with asthma also have allergies4
1.
2.
3.
4.
NCHS. Asthma prevalence, health care use and mortality 2002. Available at: http://www.cdc.gov/nchs/Default.htm.
NCHS. Ambulatory care visits 1999–2000. Available at: http://www.cdc.gov/nchs/Default.htm.
Milgrom H. Understanding allergic asthma [AAAAI News Release]. June 18, 2003.
HØst A, Halken S. Allergy. 2000;55:600-608.
CHDs URDs
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LRDs
The “One Airway” Concept
LRDs
• Common inflammatory process links upper and lower airways1
– Asthma and allergic rhinitis commonly co-exist2,3
– In concomitant disease, experts recommend evaluation and treatment of one
condition to aid management of the other4
– Asthma management guidelines from ARIA,4 the NIH,5 AAFP,6 and AAAAI7
encourage treatment of AR (and other URDs) to help control asthma
1.
2.
3.
4.
5.
6.
7.
Bachert C, et al. Immunol Allergy Clin N Am. 2004;24:19-43.
Nayak AS. Allergy Asthma Proc. 2003;24:395-402.
Halpern MT, et al. J Asthma. 2004;41:117-126.
Bousquet J, et al. Allergic Rhinitis and its Impact on Asthma (ARIA). Allergy. 2002;57:841-855.
NIH. Guidelines for the Diagnosis and Management of Asthma.1997. NIH publication 97-4051.
AAFP. Asthma & Allergy Resource Guide. 2004:18.
AAAAI. The Allergy Report. 2000;2:33,54.
CHDs URDs
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Summary
LRDs
LRDs
NIH Asthma Guidelines1
Trigger identification/control is primary management step
• “For at least those patients with persistent asthma on daily medications,
the clinician should:
– Identify allergen exposures
– Use the patient’s history to assess sensitivity to seasonal allergens
– Use skin testing or in vitro [blood] testing to assess sensitivity
to perennial indoor allergens
– Assess the significance of positive tests in context
of the patient’s medical history”
1. NIH. Guidelines for the Diagnosis and Management of Asthma.1997. NIH publication 97-4051.
CHDs URDs
Treatment
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Perspectives
Summary
LRDs
NIH Asthma Guidelines1 (cont’d)
LRDs
• “Use skin testing or in vitro testing to determine the
presence of specific IgE antibodies to the indoor allergens to
which the patient is exposed year round.”
Return to >> Third-party Perspectives
• Allergy testing is the only reliable way to determine
sensitivity to perennial indoor allergens.”
• For selected patients with asthma at any level of severity,
detection of specific IgE sensitivity to seasonal
or perennial allergens may be indicated as a basis for
avoidance, or immunotherapy, or to characterize the
patient’s atopic status.”
1. NIH. Guidelines for the Diagnosis and Management of Asthma. 1997. NIH publication 97-4051.
CHDs URDs
Treatment
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Perspectives
Summary
LRDs
Knowledge of Symptom Triggers Guides Management
LRDs
• Allergy testing may be conducted along with pulmonary function tests
and other diagnostic evaluations1
• In allergic asthma:
– Confirm atopy and identify specific allergic triggers for avoidance counseling,
symptom reduction, and control of severity and comorbid AR
• In non-allergic asthma:
– Rule out atopy to focus on possible non-allergic triggers
– Prevent needless control measures
1. NIH. Practical Guide for the Diagnosis and Management of Asthma. 1997. NIH publication 97-4053.
CHDs URDs
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CAP RAST
Perspectives
Summary
LRDs
LRDs
Asthma Management Options
Specific IgE-Positive/Abnormal
Atopic Etiology
Specific IgE-Negative/Normal
Non-Atopic Etiology
Specific Allergen Avoidance
Focus on Non-allergic Triggers
Pharmacotherapy
Inadequate Response
• Allergy Rx not helpful
• Controller(s)
• Rescue Rx
Pharmacotherapy
•
•
•
•
Treat AR (eg, NSAs)
LTRAs
Controller(s)
Rescue Rx
Adequate
Response
Inadequate
Response
Adequate
Response
Referral?
Stop
Inadequate Response
Referral?
Stop
CHDs URDs
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Perspectives
Summary
LRDs
What Is Happening to Treatment?
Treatment
• Mechanism of disease is better understood
– Means that treatments are nearer the root cause
• Therapeutic specificity is increasing
– Diseases are different and differentiation is key
– The mechanism of action of drugs is more specific than ever
– Diagnostic precision by PCP is necessary
• New diagnostic technology must be employed
CHDs URDs
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LRDs
Market Review: The Role of Diagnostics in Pharmacotherapy
Treatment
Medications for Respiratory Allergy
Treatment
Progression
1st Generation
Antihistamines
(1970s)
Non-sedating
Antihistamines
(1990s)
Mode(s) of
Action
Antihistamine effect
+
Anticholinergic effect
Treatment Results
Non-specific resolution
of symptoms regardless
of etiology
Montelukast
(2002)
Anti-IgE Vaccine
(2003)
Antihistamine effect
with very little
anticholinergic effect
Leukotriene antagonist
Binds to IgE;
Suppression of IgE
response
More specific
resolution of symptoms
primarily due to atopic
etiology — necessitates
more specific diagnosis
Specific resolution
of symptoms of atopy
by blocking another
mediator pathway
Highly specific
resolution of symptoms
due to IgE response
only — necessitates
perfect diagnosis
Highly specific
treatment
$$$$$$
Therapeutic
Approach
Broad (shotgun)
Introduction of
“D” formula creates less
specific treatment
Very specific to
atopy — necessitates
even more accurate
diagnosis (Doctors
report marginal
response for AR with
Singulair — could
be 65% are not allergic)
Cost
$
$$
$$$
CHDs URDs
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Perspectives
Summary
LRDs
Disease Paradigms
Treatment
Diabetes Mellitus Type 2
Hx & PE
lab tests
diet & exercise
pharmacotherapy
diet & exercise
pharmacotherapy
?
pharmacotherapy
Hypercholesterolemia
Hx & PE
lipid profile
CHDs, URDs, LRDs
Hx & PE
IgE profile
avoidance
CHDs URDs
Treatment
CAP RAST
Perspectives
Summary
LRDs
CAP RAST®
CAP RAST: Gain Knowledge to Guide Treatment
• FDA-cleared quantitative measure of specific IgE
• Only a single blood draw required
• Covered under most insurance plans
• Accuracy superior to RASTTM*1
– Next-generation assay offers consistently improved sensitivity,2
– De facto standard, documented in >2,700 peer-reviewed publications3
• In vitro blood testing and skin prick testing (SPT) viewed as interchangeable4
• CAP RAST is available throughout the nation from all major reference and
clinical laboratories, including Quest Diagnostics, NS-LIJ & BioReference
* RAST is a trademark of Pharmacia Diagnostics.
1. Williams PB, et al. J Allergy Clin Immunol. 2000;105:1221-1230.
2. Szeinbach SL, et al. Ann Allergy Asthma Immunol. 2001;86:373-381.
3. Johansson SGO. Expert Rev Mol Diagn. 2004;4:273-279.
4. Hamilton RG. In: Pediatric Allergy: Principles and Practice. Mosby-Year Book, Inc; 2003:233-242.
CHDs URDs
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®
CAP
CAP RAST
RAST
Perspectives
Summary
LRDs
Solid-phase Protein Binding Capacity Comparison
•CAP RAST cellulose
polymer binds almost
150 times more protein
than a passively coated
tube, well or bead, and
about 250 percent more
protein than a paper
disc.
Solid Phase
CHDs URDs
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CAP RAST
Perspectives
Summary
H. Drevin, 1989
LRDs
A. Kober,
2004
CAP RAST®
Accuracy of Immunoassays for Specific IgE
Line represents minimum acceptable R2
performance values
1.0
.96 - .98
.82
.65
Ideal Test (Correlation
Coefficient)
Newest generation:
CAP RAST
RAST/
Modified
RAST
Alastat/
3gAllergyTM**
*The authors noted that regression values below 0.80 reflect poor performance in the ability to correctly detect levels of specific IgE antibodies. ONLY CAP RAST
had consistently acceptable regression values.
**Alastat was recently replaced by 3gAllergy. Studies show 93% agreement between both methods.
Williams PB, et al. J Allergy Clin Immunol. 2000;105:1221-1230.
CHDs URDs
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®
CAP
CAP RAST
RAST
Perspectives
Summary
LRDs
CAP RAST
Predictive Value vs. Skin Prick Testing (SPT)*
Return to previous slide
In vitro†
SPT
Sensitivity (%)
87.2
93.8
Specificity (%)
90.5
80.1
PPV (%)
91.1
90.1
NPV (%)
86.4
87.1
Clinical Efficiency (%)
88.8
89.2
Performance parameters
• Authors concluded that CAP RAST Specific IgE blood test and SPT values both
exhibited excellent efficiency1
*Adapted from Reference 1.
†CAP RAST Specific IgE blood test was used in this study.
1. Wood RA, et al. J Allergy Clin Immunol. 1999;103:733-779.
CHDs URDs
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®
CAP
CAP RAST
RAST
Perspectives
Summary
LRDs
Profiles Carefully Designed
CAP RAST
• Profiles engineered to detect >95% of patients with allergy1-3
• Regional respiratory profiles include key indoor/outdoor allergens
selected according to:
– Geographic pollen patterns
– Regional disease prevalence
– Cross reactivity to other allergens in each inhalant class
• Allergy March profiles include key food/inhalant allergens
– Six foods account for 90% of food allergy reactions in children 4
– Inhalants include common/cross-reactive indoor and outdoor allergens
– Generally recommended for children ≤6 years of age, based on symptoms
1.
2.
3.
4.
Sampson HA, Ho DG. J Allergy Clin Immunol. 1997;100:444-451.
Yunginger JW, et al. J Allergy Clin Immunol. 2000;105:1077-1084.
Poon AW, et al. Am J Man Care. 1998;4:969-985.
AAAAI. The Allergy Report. 2000;3:69.
CHDs URDs
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®
CAP
CAP RAST
RAST
Perspectives
Summary
LRDs
Understanding Total IgE1
CAP RAST
• Total IgE often of little practical value when considered alone
• Levels rarely high when specific IgE titers are not
• Lacks sensitivity as a rule-out screen:
Specific IgE levels may be significantly high when total IgE is low/normal
• Extremely high total IgE may be seen in some very rare non-atopic conditions2:
– Certain immunodeficiency diseases (including HIV)
– IgE myeloma
– Drug-induced interstitial nephritis
– Graft-versus-host disease
– Parasitic diseases
– Skin diseases in addition to eczema
– Hyper-IgE syndrome (dermatitis, recurrent pyogenic infection)
1. Fromer LM. J Fam Pract. 2004;suppl:S4-S14.
2. AAAAI. The Allergy Report. 2000;1:35.
CHDs URDs
Treatment
®
CAP
CAP RAST
RAST
Perspectives
Summary
LRDs
Understanding Total IgE
CAP RAST
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Interpretation of Total IgE* Results
Total IgE Reading
Specific IgE Reading
Negative
(Normal)
Non-allergic
Patient
Negative
(Normal)
Scenario A
Positive
(Abnormal,
Elevated)
Positive
(Abnormal,
Elevated)
Rare1
Scenario B
Allergic
Patient
Allergic
Patient
Scenario C
Scenario D
*Includes URDs (Upper Respiratory Diseases), CHDs (Childhood Diseases), and LRDs (Lower Respiratory Diseases)
1. AAAAI. The Allergy Report. 2000;1:35.
CHDs URDs
Treatment
®
CAP
CAP RAST
RAST
Perspectives
Summary
LRDs
Summary
Summary
• Diagnostic precision leads to evidence-based medical care
– Improves patient care
– Creates better patient satisfaction
– Provides more appropriate referrals
• CAP RAST Specific IgE blood test is an accurate test to differentiate
atopic from non-atopic patients
• Experts, specialty organizations, and government agencies support
allergy testing in primary care
CHDs URDs
Treatment
CAP RAST
Perspectives
Summary
LRDs
URD Inhalant
Panel
Interpretation
Of
Results
CHDs URDs
Treatment
CAP RAST
Perspectives
Summary
LRDs