FRACTIONAL EXHALED NITRITIC OXIDE

**這個檢查的儀器是用研究經費購買的，需自費1000元，檢查結果一般不會上傳報告系統，會直接拿給開單醫師打在門診或病歷記錄裡。
**打報告要先看病人的病歷記錄，區分成兩類：第一類是有類氣喘症狀，但是尚未開始使用ICS (inhaled corticosteroid)，針對這一類的病人，FeNO的結果可以預測病人是否對ICS會有療效。第二類是已經被診斷為氣喘的病人，針對這一類的病人，FeNO可以協助判斷是否有過敏性呼吸道發炎(allergic airway inflammation)。
**FeNO升高並不表示病人一定有氣喘，有些具有過敏體質(atopic)但沒有氣喘的病人FeNO也會升高。
**FeNO在非過敏性發炎表現型(allergic phenotype)的氣喘病患可能不會升高。

For Children <12 y/o

FENO	Asthma-like NOT treated with ICS	Established asthma
<25 ppb	THE FENO TEST SUGGESTS THAT A RESPONSIVENESS TO ICS IS UNLIKELY.	THE FENO TEST SUGGESTS THAT ALLERGIC AIRWAY INFLAMMATION IS UNLIKELY.
25-50 ppb	THE FENO TEST SUGGESTS THAT A RESPONSIVENESS TO ICS IS POSSIBLE. RECOMMEND CAUTIOUS INTERPRETATION.	THE FENO TEST SUGGESTS THAT ALLERGIC AIRWAY INFLAMMATION IS POSSIBLE. RECOMMEND CAUTIOUS INTERPRETATION.
>50 ppb	THE FENO TEST SUGGESTS THAT A RESPONSIVENESS TO ICS IS LIKELY.	THE FENO TEST SUGGESTS THAT ALLERGIC AIRWAY INFLAMMATION IS LIKELY.

 

 

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For patients with asthma-like symoptoms NOT treated with ICS

FeNO <25 ppb (<20 ppb for children <12 years)
THE FENO TEST SUGGESTS THAT A RESPONSIVENESS TO ICS IS UNLIKELY.

FeNO 25-50 ppb (20-35 ppb for children <12 years)
THE FENO TEST SUGGESTS THAT A RESPONSIVENESS TO ICS IS POSSIBLE. RECOMMEND CAUTIOUS INTERPRETATION.

FeNO >50 ppb (>35 ppb for children <12 years)
THE FENO TEST SUGGESTS THAT A RESPONSIVENESS TO ICS IS LIKELY.

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For patients with estabilished asthma
FeNO <25 ppb (<20 ppb for children <12 years)
THE FENO TEST SUGGESTS THAT ALLERGIC AIRWAY INFLAMMATION IS UNLIKELY.

FeNO 25-50 ppb (20-35 ppb for children <12 years)
THE FENO TEST SUGGESTS THAT ALLERGIC AIRWAY INFLAMMATION IS POSSIBLE. RECOMMEND CAUTIOUS INTERPRETATION.

FeNO >50 ppb (>35 ppb for children <12 years)
THE FENO TEST SUGGESTS THAT ALLERGIC AIRWAY INFLAMMATION IS LIKELY.

(Chest 2016;149(5): 1340-1344)