1 Pulmonary Medicine, Department of Pediatrics, Vanderbilt University Medical Center, Nashville, TN; Allergy, Pulmonary, and Critical Care Medicine, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN. Electronic address: lisa.young@vanderbilt.edu.
2 Section of Pulmonology, Department of Pediatrics, Baylor College of Medicine, Houston, TX.
3 Department of Pediatric Radiology, Texas Children's Hospital, Houston, TX.