The prevalence of respiratory allergies and their effects on the course of cystic fibrosis (CF) were studied in 63 patients. Fifteen patients (24%) had respiratory allergies as defined by history, physical examination, positive allergy skin tests, nasal and peripheral eosinophilia, and reversible airway obstruction. Serum immunoglobulins on these 15 allergic CF and 22 nonallergic CF patients were elevated when compared with those in normal age-matched controls. The allergic CF patients had significantly higher IgE levels (mean 598 international units [IU] compared to 281 IU); IgG, IgM, and IgA levels were similar in the two CF groups.
The clinical condition of the allergic CF patients, (Shwachman score) was better than the nonallergic, suggesting some modulating effect of respiratory allergy on the severity of the disease.