This article is part of MPR‘s coverage of the ACAAI 2019 meeting, taking place in Houston, TX. Our staff will report on medical research related to allergies, asthma, and more conducted by experts in the field. Check back regularly for more news from ACAAI 2019.

HOUSTON — Fractional exhaled nitric oxide (FeNO) values may help in the identification of cough variant asthma in patients with chronic cough, according to study results presented at the 2019 Annual Scientific Meeting of the American College of Allergy, Asthma,  & Immunology, held November 7 to 11 in Houston, Texas.

Cough variant asthma — a frequently underdiagnosed condition — is characterized by a nonproductive, dry chronic cough without wheezing or shortness of breath. The use of FeNO is common to evaluate patients who are suspected to have cough variant asthma.

Patients in the study presented had chronic cough, normal spirometry, and abnormal Asthma Control Test (ACT) results (n=32; mean age, 42.5 years). Another 9 healthy control patients were also enrolled (mean age, 47 years). All patients had normal chest x-rays and eosinophil counts and were skin test-positive for environmental allergens. Investigators used a FeNO analyzer to take FeNO measurements.

Among patients with chronic cough, 91% (n=29) had elevated FeNO measurements with a mean value of 64.4. The optimal normal FeNO cutoff value was 25 ppb. Meanwhile, healthy controls had normal FeNO measurements (mean FeNO values, 16 ppb). Abnormal ACT scores (15.4) were found in 60% of patients with chronic cough.

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According to the investigators, FeNO “may not only offer a helpful algorithm to unravel the clinical conundrum of [chronic cough]” but may also lead to reductions in misdiagnoses and healthcare costs.

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Nsouli T, Diliberto N, Nsouli S, Zamora S, Nsouli A, Bellanti J. Lack of concordance between FeNO and spirometry in patients with chronic cough. Presented at: American College of Allergy, Asthma, & Immunology Annual Scientific Meeting 2019; November 7-11, 2019; Houston, TX. Abstract A202.

This article originally appeared on Pulmonology Advisor