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TRANSCRIPT
Introduction
Allergic rhinitis (AR) is a common chronic
disease which is diagnosed by a variety of
clinical parameters. There is currently no
widely accepted screening test for AR.
Measurement of total serum IgE has not
been recommended for use as a screening
test due to prior limitations. However, this is
a low cost test that may in fact have value in
screening selected populations for AR. The
aim of this study is to determine the utility of
total serum IgE in the diagnosis of AR.
Methods
The charts of 1073 patients undergoing
laboratory testing for the workup of allergic
rhinitis were retrospectively reviewed. Data
on patient demographics, clinical
parameters, and results of serum specific
IgE levels were recorded. Multivariate
logistic regression was performed to
ascertain the influence of various factors on
the likelihood of a positive in vitro tests. The
predictive values of total serum IgE in
forecasting a positive or negative in vitro
specific allergy test was determined.
Results
Total serum IgE demonstrated an
incremental statistically and clinically
significant positive and negative predictive
values for identifying positive in vitro allergy
tests. Differences in age, gender, ethnicity,
clinical diagnosis, use of medications, month
in which testing was performed, and the
presence of co-morbid conditions were not
statistically significant.
Conclusions
Total IgE levels offer clinical utility as a low-
cost screening measure for patients with
suspected AR. Total IgE level is
independent of multiple demographic,
seasonal, and clinical factors.
Significance of Serum Total IgE in the Diagnosis of Allergic Rhinitis
Daniel Chung MA 1, KT Park MD 2, Bharat Yarlagadda MD 1, Elizabeth Mahoney MD 1, Michael Platt MD 1
1 Department of Otolaryngology – Head & Neck Surgery, Boston University School of Medicine, Boston, MA 2 Division of Gastroenterology, Lucille Packard Children’s Hospital, Stanford University, Palo Alto, CA
INTRODUCTION RESULTS
CONCLUSIONS
DISCUSSION
METHODS
ABSTRACT
CONTACT
n % Odds Ratio (CI) P value
Gender Male 431 40.2
Female 642 59.8
Age Mean 36.9
Range 1-91
Ethnicity White 296 27.6 1.7 (0.37 – 8.28) 0.48
Black 330 30.8 0.9 (0.19 – 3.92) 0.84
Hispanic 245 22.8 1.1 (0.23 – 5.35) 0.90
Asian 72 6.7 2.0 (0.27 – 15.4) 0.50
Other 79 7.4 0.8 (0.11 – 6.00) 0.83
Uncertain 51 4.8
Primary Rhinitis 70.2
Diagnosis Laryngitis 2.5
Otitis 1.4
Rash 0.2
Angioedema 1.5
Chronic
Sinusitis 18.9
Other 5.3
Total IgE < 10 148 13.8 N/A
(IU/ml) 10 – 50 303 28.3 8.2 (2.21 – 30.3) 0.002
51 – 100 170 15.9 41.3 (9.31 – 182.6) < 0.001
101 – 150 90 8.4 99.8 (13.5 – 741.0) < 0.001
> 150 362 33.8 76.0 (17.0 – 340.0) < 0.001
Associated Nasal Polyps 119 11.1 0.1 (0.15 – 0.67) 0.02
Diseases Asthma 264 24.6 1.7 (0.71 – 4.0) 0.23
Anaphylaxis 39 0.04 2.3 (0.15 – 34.9) 0.54
Allergic rhinitis (AR) is a common chronic disease which has
significant impact on quality of life, loss of productivity, and
financial expenditure1,2. Diagnosis of AR is performed by clinical
parameters as well as measurement of specific IgE reactivity
through in vitro or in vivo methods. There is currently no
accepted screening test for differentiating AR from diseases with
similar symptoms. The measurement of total serum IgE level is
a low-cost test that is used in diagnosis of AR , however, current
guidelines do not endorse its use in clinical practice3,4. The aim
of this study is to identify the clinical usefulness of total serum
IgE in the diagnosis of AR.
A retrospective chart review was performed for patients being
evaluated for AR at an academic otolaryngic allergy clinic over
a 5 year period. Charts were reviewed for demographic data,
clinical diagnoses, and total and specific IgE results. STATA
Software was used to construct a multivariate logistic
regression model to determine the likelihood of patients having
a positive specific in vitro test for at least one antigen (>0.35
IU/ml), given clinically relevant covariates (Table 1). The
positive and negative predictive value total IgE level in the
diagnosis of AR, as defined by clinical manifestations and a
positive specific IgE in vitro test, were calculated.
Table 1. Demographics of the sample population and odds ratio of a
positive in vitro test after multivariate logistic regression of the
influence of pre-test variables.
Figure 1. Positive predictive value and odds ratio of total serum IgE
(IU/ml) in identifying a positive specific IgE by in vitro methods.
13
40.9
65.3
77.8
89.6
1 8.19
41.3
99.8
76
0
20
40
60
80
100
< 10 10 - 50 51 - 100 101 - 150 > 150PPV Odds Ratio
Signs and symptoms of allergic rhinitis overlap
with other clinical syndromes that display
similar findings. Due to increased costs and
possible risks of allergy testing, a simple and
low-cost screening test would be an important
tool for identifying patients with AR.
Total serum IgE demonstrated favorable
positive and negative predictive values for
patients with allergy symptoms. The most
clinically useful values are found at the
extremes of these tests.
Total serum IgE level was not affected by
primary clinical diagnosis, patient
demographics, medications (other than oral
steroids), associated conditions (asthma or
anaphylaxis), or seasonal variation.
Nasal polyps demonstrated a negative
association which may be due to the screening
of these patients without classical allergy
symptoms.
REFERENCES 1Fajraoui, et al. Contribution of serum total immunoglobulin E
measurement in the diagnosis of respiratory allergic disease. Tuni
Med. Jan;86(1):32-7. 2008.
2Meltzer, et al. The economic impact of allergic rhinitis and current
guidelines for treatment. Ann Allergy Asthma Immunol 106, S12-16.
2011.
3Wallace, et al. The diagnosis and management of rhinitis: an updated
practice parameter. J Allergy Clin Immunol. Aug;122(2 Suppl):S1-84.
2008.
4Kerkhof, et al. Role and interpretation of total serum IgE
measurements in the diagnosis of allergic airway disease in adults.
Allergy. Sep;58(9):905-11. 2003.
Elevated total IgE has a high positive predictive
value for identification of in vitro specific IgE in
the diagnosis of allergic rhinitis
Total IgE level has a high negative predictive
value at the lower range, suggesting that specific
IgE testing may not be warranted in those
patients with low total IgE (< 10 IU/ml).
Further analysis is needed to determine the
effect of specific allergy sub-classes on total IgE
test statistics.
There were a total of 1,232 patients identified who had both
serum total IgE level and specific IgE reactivity by in vitro testing.
One hundred and fifty nine patients were excluded due to
incomplete total IgE result (5), insufficient clinical information
(39), use of oral steroids (22) and insufficient allergens tested on
specific IgE panels (93).
Total serum IgE demonstrated an incremental statistically and
clinically significant positive predictive value for identifying
positive in vitro allergy tests. (Figure 1). Differences in age,
gender, ethnicity, clinical diagnosis, use of medications, month in
which testing was performed, and the presence of co-morbid
conditions were not statistically significant (Table 1). The
presence of nasal polyps revealed a negative association with
positive allergy testing. The negative predictive value ranged
from 86.9 to 60.6 depending on total IgE cutoff level for
diagnosis of a “negative” test.
Figure 2. Negative predictive value of total serum IgE (IU/ml) in
identifying a negative specific IgE by in vitro methods.
86.9
69.2 66.3 60.6
0
20
40
60
80
100
< 10 10 - 50 51 - 100 101 - 150
NPV
Michael Platt, MD
Boston University School of Medicine
Dept. of Otolaryngology –
Head & Neck Surgery
Email: [email protected]
Phone: 617-638-8000
Website: bu-ent.com