Inhaled Dry Powder Mannitol Treatment in Pediatric Patients with Cystic Fibrosis: Evaluation of Clinical Data in a Real-World Setting.

Background: Cystic fibrosis (CF) is a genetic disorder, in which defective clearance of airway secretions leads to progressive lung function loss. Inhaled mannitol is used to increase sputum and mucociliary clearance. There are little data from real-world studies on the effectiveness of mannitol in children. Our objective was to evaluate the spirometry and clinical results of mannitol in pediatric patients. Methods: We retrospectively reviewed the records of 30 children and adolescents with CF receiving inhaled mannitol who were already on recombinant human deoxyribonuclease (rhDNase) treatment. The change in forced expiratory volume in 1 second (FEV 1 ) from baseline at 2-4 months was the primary outcome. Secondary measures were other spirometry results, body mass index (BMI), hospital admissions, sputum characteristics, and positive bacterial colonization. Results: Compared to baseline, we found significant improvement in percent predicted FEV 1 at 2-4 months of treatment; 84.50 (58.00-99.00) vs. 96.00 (66.00-106.00) ( P  = 0.0007). The absolute change in FEV 1 was +11.5% at 2-4 months, +6.5% at 5-7 months, and +4% at 8-12 months. Also, significant improvements in other spirometry results were observed. Adolescents had significantly lower FEV 1 results, but the improvement in their lung function was sustained for a more extended period than children. Mannitol provided easier sputum removal, increased sputum volume, significant decline in hospitalizations, and significantly fewer patients with positive sputum cultures. A significant increase in BMI at 8-12 months was observed. Cough was the most frequent adverse effect. Conclusion: In a real-world setting, our results demonstrated that adding mannitol to rhDNase therapy is tolerable in pediatric patients with CF and may provide improved spirometry and clinical outcomes. In addition, our results showed that mannitol provided recovery in overall lung function at 2-4 months, which was sustained up to 12 months together with improved BMI, easier sputum removal, and a decline in bacterial colonization and hospital admissions. However, cough was the most frequent side effect.