Asia Pac Allergy.  2014 Jul;4(3):149-155. 10.5415/apallergy.2014.4.3.149.

Reference ranges for induced sputum eosinophil counts in Korean adult population

• Kim MY
• Jo EJ
• Lee SE
• Lee SY
• Song WJ
• Kim TW
• Hur GY
• Lee JH
• Kim TB
• Park HW
• Chang YS
• Park HS
• Min KU
• Cho SH

• KMID: 2397092
• DOI: http://doi.org/10.5415/apallergy.2014.4.3.149

Abstract

BACKGROUND
Induced sputum analyses are widely utilized to evaluate airway inflammation in asthmatics. However, the values have not been examined in Korean adults.
OBJECTIVE
The purpose of this study is to determine reference ranges for induced sputum eosinophils and their influencing factors in Korean adults.
METHODS
A total of 208 healthy nonasthmatic adults were recruited. Sputum induction and processing followed the international standard protocols.
RESULTS
Adequate sputum samples were successfully collected from 81 subjects (38.9%). The upper 90 percentile for sputum eosinophil was calculated as 3.5%. The median value of eosinophil count percentage was significantly higher in subjects with atopy than those without atopy (median, 1.6%; range, 0-11.0% vs. median, 0%; range 0-3.6%, p=0.030). However, no significant correlations were found with age, gender, body mass index, smoking status, blood eosinophil, or fractional exhaled nitric oxide levels.
CONCLUSION
Current study was the first attempt to determine the reference ranges of induced sputum eosinophils in Korean adults. The cutoff value for sputum eosinophilia was 3.5%, and was significantly associated with atopy.

Keyword

Eosinophils; Sputum; Healthy volunteers; Reference values

MeSH Terms

Adult*
Body Mass Index
Eosinophilia
Eosinophils*
Healthy Volunteers
Humans
Inflammation
Nitric Oxide
Reference Values*
Smoke
Smoking
Sputum*
Nitric Oxide
Smoke

Figure

• 

  Fig. 1 Distribution of induced sputum eosinophils in 81 normal subjects.

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  Fig. 2 Distribution of induced sputum eosinophils of normal subjects according to presence of atopy (20 atopic subject and 43 nonatopic subjects).

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