Emily is 21 years old and has suffered from allergies for many years. She was diagnosed with asthma 5 years ago.
Emily has been prescribed a combination of an ICS (once daily) and a long-acting beta-agonist (LABA, twice daily), along with a short-acting beta-agonist (SABA, 0.5 mg/dose) when needed. However, she tends to forget her medication.
Emily experiences breathing problems during exercise, when she has a cold, or is exposed to smoke or intense smells. Last winter she experienced asthma when skiing. Because Emily plans to spend her winter break skiing, she is now motivated to take control of the situation.
• A RAST test shows that she is sensitized towards cat (25.1 kU/l), dog (9.2 kU/l), horse (8.1 kU/l), birch (22.3 kU/l), timothy (21.6 kU/l) and Cladosporium (1.5 kU/l) allergens
• The FENO value is 55 ppb
• Why does Emily have symptoms despite the fact she is prescribed medication?
• What does the FENO value reveal about the inflammation?
Interpretation
The FENO value strongly suggests an ongoing eosinophilic inflammation, which should respond to steroid treatment. However, Emily is already on ICS.
• Does she take the medication?
• Does she use the correct inhalation technique?
• Has anything been changed in the allergen exposure?
• Is she taking the optimal steroid dose?
• Has her asthma deteriorated?
• Is she steroid-resistant?
The asthma nurse gives Emily detailed instructions on how to use the inhaler device and the dose of ICS/LABA is increased.
Two weeks later the FENO value is 29 ppb. The dose of ICS/LABA is further increased and after another 2 weeks the FENO value is down to 22 ppb.
The dose of ICS/LABA is further increased.
Visit 3
2 weeks later the FENO value is down to 22 ppb. Emily is feeling much better.
Measuring the FENO value helped improve Emily´s motivation and compliance to the prescription. Emily had a case of poorly controlled asthma, most likely due to non-compliance, as well as to a prescribed ICS/LABA dose that may have been too low. The inflammation is currently under control and she now has a much better understanding of the importance of using her medication regularly as her doctor prescribed.