Clinical Cases

Exhale Nitric Oxide in a Patient with Shortness of Breath

Reviewed By Allergy, Immunology & Inflammation Assembly

Submitted by

Mani Latifi, MD

Clinical Fellow, Pulmonary/Critical Care Medicine

Cleveland Clinic Foundation

Cleveland, OH

Siddharth Dugar

Clinical Fellow, Critical Care Medicine

Cleveland Clinic Foundation

Cleveland, OH

Raed Dweik, MD

Professor of Medicine

Director, Pulmonary Vascular Program

Cleveland Clinic Foundation

Cleveland, OH

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A 41-year-old African-American female with a past medical history of diabetes type II, hypertension, and hypercholesterolemia presents to pulmonary clinic for evaluation of shortness of breath.  She has no history of childhood asthma; however, at age 26 she was diagnosed clinically with asthma based solely on symptoms during an unrelated hospitalization. She was given an albuterol inhaler, which she used initially for 1 year.  She reports her shortness of breath and cough are worse with exposure to cold air and during “pollen season.” She also reports nocturnal awakenings roughly 3 times per month.  She denies any sinus disease history, including post-nasal drip, or symptoms consistent with gastroesophageal reflux disease.

Her medications include Aspirin 81 mg daily, Simvastatin 20 mg once daily, and Amlodipine 10 mg daily.  She has a 1 pack per day smoking history from age 21-25 and has since quit.  She is divorced with 2 children and has no pets.  She works as a hotel receptionist and denies any known occupational exposures. 

Physical Exam

On physical exam, she appeared comfortable in no acute distress.  Vital signs were unremarkable with SpO2 98% on room air.  Cardiac exam revealed normal rate and rhythm, audible S1/S2, and no rubs, murmurs or gallops.   Pulmonary exam was significant for diffuse expiratory wheezing in upper and lower lung zones bilaterally.  There were no crackles or rales.  Extremities were non-edematous with no notable digital clubbing. 


Complete blood count with differential and basic metabolic panel were within normal limits.   Chest x-ray was unremarkable. 

Pulmonary Function Tests:

  • FEV1/FVC 89%; FEV1 2.16L (91%); FVC 3.06 (101%); post-bronchodilator FEV1 2.25 (increase of 4%)

Fractional nitric oxide concentration in exhaled breath (FeNO): 61 ppb

Question 1

Which of the following is the next best step to help support a diagnosis


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