Eric is 31 and suffers from chronic rhinitis and seasonal allergies during spring and midsummer. In addition, he has recently developed breathing problems.
Eric uses antihistamines for his seasonal allergies, but recently experienced breathing problems while jogging.
• Physical examination is normal.
• FENO is 75 ppb.
• Spirometry is normal.
• What does the examination, especially the FENO value, tell you?
The FENO value strongly suggests an ongoing eosinophilic inflammation, which should respond to steroid treatment.
Eric’s rhinitis and allergy symptoms have progressed to an eosinophilic inflammation in the lower airways, which causes the airways to become hyperreactive. This should be treated with ICS. The high FENO value indicates that he will most likely have a response. Therefore, the patient is prescribed fluticasone.
Eric was prescribed 500 μg of fluticasone twice daily. His FENO value fell one month later to 30 ppb and he had no symptoms. This shows that he responded well to steroid treatment.
The doctor suggested that the ICS dose should be reduced to 250 μgs twice daily and asked Eric to come back three months later (as per NHLBI guidelines5) or to contact the doctor sooner if he experienced any symptoms.
On his next visit, Eric still did not show any symptoms and his FENO value was 28 ppb. The doctor reduced Eric’s medication to 250 μgs per day and suggested he return in three months. Eric continued on the lower dose of fluticasone and returned to the clinic three months later. On examination his FENO value was 25 ppb and he still did not experience any symptoms.
The doctor prescribed an even lower dose, 50 micrograms twice daily, but warned Eric to be very observant for symptoms, especially when approaching the pollen season.
The following spring Eric visited his doctor again and was happy to report he had no symptoms. His FENO value was 27 ppb. He is using his antihistamines and the doctor and Eric both feel that his allergies and asthma are under control. Eric will continue with a low dose of ICS.