Asthma-like symptom or "cystic fibrosis asthma"?

The diagnosis of asthma is still a difficult problem in cystic fibrosis. There is no consensus on how to define "CF asthma". The aim of this study was to determine the role of bronchodilator response and laboratory evidence of allergy in "CF asthma".

Patients aged ≥6 years with evaluated bronchodilator response and characteristics of atopy were included in the study. Patients diagnosed with Allergic Bronchopulmonary Aspergillosis or pulmonary exacerbation were excluded.

A total of 204 CF patients were evaluated, and 40 who met the criteria were included. Asthma had been diagnosed in ten patients. A positive bronchodilator response was present in 47.3% of the patients tested. Aeroallergen sensitization was present in 52.5% of the patients. While the frequency of recurrent/history of wheezing, family history of atopy and elevated total immunoglobulin E were similar (p> 0.05), the frequencies of inhaled medication use and coexistence of asthma were statistically higher in the group with positive allergen sensitization (p<0.05). The frequencies of positive bronchodilator response (77.7% versus 37.9%) and a family history of asthma/atopy (40% versus. 23%) were found to be similar in CF asthma and CF. There were significant increases in total IgE and allergen-specific IgE and an increase in the frequency of aeroallergen sensitization in CF asthma compared to CF (p<0.05).

Although not routinely used in the evaluation of patients, allergen specific-IgE and skin prick test for aeroallergen sensitization may be used as an adjunctive test in patients with suspected clinical findings. The recognition of CF asthma may facilitate the development of targeted therapies.