Asthma Group

1. At least a one-year history of physician diagnosed asthma

2. Enrollment within 48 hours of hospitalization, and prior to hospital discharge, for an acute asthma exacerbation.

3. Age 6 - 18 years.

4. Birth at ≥ 36 weeks gestation.

5. Ability to perform acceptable and reproducible spirometry meeting American Thoracic Society guidelines.

Control Group

1. Age 6 - 18 years.

2. No prior history of asthma.

3. Birth at ≥ 36 weeks gestation.

4. Ability to perform acceptable and reproducible spirometry meeting American Thoracic Society guidelines.

Airflow Obstruction and Biomarkers of Airway Inflammation During and Following Acute Exacerbations of Childhood Asthma