Mannitol dry powder challenge in comparison with exercise testing in children.

Area of Science:

• Pediatric Respiratory Medicine
• Clinical Immunology
• Pulmonary Function Testing

Background:

• Mannitol dry powder (MDP) challenge is an established indirect bronchial provocation test in adults.
• Its utility and validation in pediatric populations are not well-established.
• Asthma diagnosis in children often relies on various provocative tests.

Purpose of the Study:

• To compare the feasibility, validity, and clinical significance of the MDP challenge against exercise testing in children.
• To assess the agreement and predictive values of MDP challenge for exercise-induced bronchoconstriction.
• To determine the suitability of MDP challenge as a diagnostic tool in pediatric asthma evaluation.

Main Methods:

• A cohort of 99 children (aged 6-16 years) with suspected asthma underwent standardized exercise testing followed by an MDP challenge.
• Agreement between tests was analyzed using Cohen's kappa and receiver operating characteristic (ROC) curves.
• Feasibility, side effects, and duration of both challenge tests were recorded.

Main Results:

• The MDP challenge was well-accepted, shorter in duration, and had fewer side effects than exercise testing.
• The MDP challenge was positive in 29% of children, while exercise testing was positive in 21%.
• Both tests demonstrated moderate agreement (κ = 0.58), with an area under the ROC curve of 0.83 for the MDP challenge.

Conclusions:

• The mannitol dry powder challenge test is feasible and well-tolerated in children.
• It serves as a suitable alternative to exercise testing for bronchial challenge in pediatric populations.
• MDP challenge demonstrates good validity for identifying exercise-induced bronchoconstriction.