J ALLERGY CLIN IMMUNOL

FEBRUARY 2012

AB4 AbstractsSATURDAY

13 Usefulness of Impulse Oscillometry In Children WithEosinophilic Bronchitis

Y. Kim1, K. Kim1, J. Baek1, H. Park1, H. Lee2, M. Sohn1, K. Kim1; 1De-

partment of Pediatrics and Institute of Allergy, Severance Biomedical Sci-

ence Institute, Brain Korea 21 Project for Medical Science, Yonsei

University College of Medicine, Seoul, REPUBLIC OF KOREA, 2Kwan-

dong University College of Medicine, Goyang, REPUBLIC OF KOREA.

RATIONALE: Eosinophilic bronchitis (EB) has been shown to resolve,

whereas it has been shown to progress to asthma in some patients, despite

treatment with inhaled steroids. It is controversial whether EB is a pre-form

of asthma.We evaluated pulmonary function by impulse oscillometry

(IOS) and airway inflammation by measuring fractional exhaled nitric

oxide (FeNO) of children with EB in comparison of those with asthma and

healthy children as a control.

METHODS: A total of 232 children with asthma, 109 with EB, and 115

control subjects were enrolled. We compared pulmonary function test

parameters and FeNO levels among three subject groups, and designated a

cutoff value of FeNO combined with IOS parameters to distinguish EB

from the control group.

RESULTS: Pulmonary function and bronchodilator response for EB in

spirometry were of normal range as well as for the control. In IOS, the

percentage change in reactance at 5 Hz (D X5) and the percentage change

in reactance area (DAX) of the EB as well as the asthma groups decreased

significantly compared to the control (P < .0001). A cutoff value to distin-

guish EB from control was D X5 is220% (sensitivity, 77.5%; specificity,

49.6%), and D AX is 230% (sensitivity, 75.0%; specificity, 46.0%) when

FeNO is 20 ppb.

CONCLUSIONS: Reversible airway obstruction in IOS and elevated

FeNO levels can be useful for evaluation of EB in children. This would

support that EB shows airway characteristics similar to those of asthma.

14 Eucapnic Voluntary Hyperventilation Screen for BronchospasmRisk During a SCUBA Dive

R. R. Rosenthal; Johns Hopkins School of Medicine, Baltimore, MD.

RATIONALE: Eucapnic Voluntary Hyperventilation (EVH) may be used

to duplicate the cold dry air exposure of a SCUBA dive. It should be useful

to evaluate the likelihood of bronchospasm in potentially susceptible

individuals who wish to dive.

METHODS: A 15 year old female student who sought enrollment in a

SCUBA diving class had an undocumented history of wheezing after a

respiratory infection in the past, was on no medications presently and had

normal pulmonary functions. Using a previously described simplified

method, she was given an EVH challenge with a target ventilation of 25

times her FEV1 (62.5% of her estimated Maximum Voluntary Ventilation)

for 6 minutes.

RESULTS: The applicant had a 24.8%decrease in her FEV1 frombaseline

at 15 minutes after the challenge and required inhaled bronchodilator to re-

store her pulmonary function to baseline values. Shewas informed that she

would be at risk of exercise induced bronchospasm triggered by the cold

dry air of SCUBA exposure during actual dive conditions. This in turn

would create the risk of arterial gas embolism, rupture of lung membranes,

mediastinal emphysema or pneumothorax due to the expansion of trapped

air upon ascent from depth and, accordingly, she was advised not to

SCUBA dive.

CONCLUSIONS: A simplified method for EVH may be conveniently

used to evaluate individuals for the risks attendant to exercise induced

bronchospasm triggered by the cold dry air typically ventilated during a

SCUBA dive.

15 BMI Does Not Correlate with PFTs in Asthma ScreeningL. A. Wiens; BreatheAmerica, Tulsa, OK.

RATIONALE: There is a positive association between asthma and

obesity, but the mechanism is unclear. Studies have compared this

relationship based on clinical symptoms without correlating objective

pulmonary function tests (PFTs) with body mass index (BMI).

METHODS: Retrospective chart reviews were performed on 36 patients

who had been evaluated for respiratory symptoms within the past 3 years.

Initial PFTand BMImeasurements were obtained prior to any intervention

by the health care provider.

RESULTS: Average age of subjects was 41.3 yearswith a range of 10 to 86

years. There were 10 males and 27 females. Knudson predive values were

used for PFTs; BMI was calculated using the following formula: [wt(lbs)/

{ht(in)xht(in)}]x703. Average BMI was 24.5 with a range of 15.0-34.9.

Average FEV1 was 82.8 % predicted with a range of 30.8 to146.6.

Regression analysis using FEV1, FVC, and FEF25-75 as dependent varia-

bles showed no correlation with BMI. (FEV1, p50.783;FVC, p50.275;

FEF25-75, p50.874) Correlation between FVC and BMI was (-.284), but

did not reach statistical significance.

CONCLUSIONS: The relationship between obesity and asthma is based

primarily on clinical symptoms, and objectivemeasurements of pulmonary

obstruction cannot be predicted by BMI. This lack of correlation would

suggest multiple factors are involved in the relationship between asthma

and obesity depending on the phenotype of each disease under study.

Screening for obesity and asthma in the same clinical setting is unlikely to

yield more positive results than either test alone.

16 Patterns of Aeroallergen Sensitization and Development ofSputum Eosinophilia and Airway Hyperresponsiveness

S. Kim1,2, W. Song1,2, T. Kim2, S. Lee2, H. Kang2, H. Park2, S. Kim2, Y.

Chang1,2, S. Cho2, K. Min2; 1Department of Internal Medicine, Seoul Na-

tional University Bundang Hospital, Seongnam, REPUBLIC OF KOREA,2Department of Internal Medicine, Seoul National University College of

Medicine, Seoul, REPUBLIC OF KOREA.

RATIONALE: Specific aeroallergen sensitization may have more influ-

ence on the development of airway inflammation and airway hyper-

responsiveness (AHR). This study was aimed to investigate the

relationship between aeroallergen sensitization pattern and development

of sputum eosinophilia and AHR.

METHODS: We retrospectively evaluated the data of skin prick test to

aeroallergens, methacholine bronchial provocation test and induced spu-

tum analysis from the patients who had performed all of three tests for the

evaluation of their allergic and respiratory symptoms.

RESULTS:Mean age of 1207 enrolled subjects was 49.9616.4 and 43.2%

were male. 51.9% of them had positive skin test response to at least one

allergen, 38.8%had sputum eosinophilia (eosinophil >_ 3%), and 23.3%had

AHR (PC20 <_ 16mg/ml). Both sputum eosinophilia and AHR were

significantly associated with sensitization to at least one perennial

allergen(OR51.8, 95%CI: 1.4-2.3; OR52.6, 95%CI: 1.9-3.5, respec-

tively) and individual allergen sensitizations to house dust mite, indoor

mold, cat, and dog, after adjusting for age and gender. There was no

significant relationship in seasonal allergens such as tree, grass and weed

pollen, outdoor mold, and cockroach.

CONCLUSION: Increased sputum eosinophilia and AHR are associated

with specific allergen sensitization, especially sensitization to indoor

perennial allergens.