The proposed research study is a cross-sectional study enrolling young children with sickle cell disease between 5 and 12 years of age. They will be screened as outpatients for consent to perform pulmonary function testing (PFT) and echocardiography. In addition, the degree of bronchodilator response will be assessed at each session. To estimate presence of pulmonary hypertension, echocardiography will be performed at the time of PFT measures.

Study Design:

1. Enroll children aged 5 to 12 years of age with sickle cell disease (HbSS, HbSC, HbS beta plus thalassemia, HbS beta zero thalassemia, and HbS OArab) who are established patients within the Duke Pediatric Sickle Cell Clinic.
2. Perform a chart review of all enrolled subjects to obtain specific details regarding birth history, nutritional status (weight, height), family history, sickle cell genotype, parental smoking history, recent laboratory parameters, parental smoking history, any concurrent conditions (atopy, asthma, airway anomaly), history of sickle cell complications and prescribed medications.
3. Perform spirometry and plethysmography with the administration of albuterol.
4. Before or after completion the PFT session, the patient will have echocardiography in the PFT lab area
5. Using medical record information, determine number of hospitalizations for any pulmonary symptoms indicative of acute chest syndrome (ACS) (dyspnea, fever, wheezing, hypoxia, cough, chest pain). In addition, we will track any respiratory or cardiac symptoms or therapies for each subject 6 years after enrollment up to age 18 years using the registry.
6. As standard of care, refer any child identified as having lung disease or pulmonary hypertension to a pediatric pulmonologist and/or cardiologist for monitoring, treatment and ongoing care.

Inclusion Criteria:

• children aged 5 to 12 years of age with sickle cell disease (HbSS, HbSC, HbS beta plus thalassemia, HbS beta zero thalassemia, and HbS OArab)
• established patients within the Duke Pediatric Sickle Cell Clinic.
• Subjects must have been full-term at birth
• any race or gender

Exclusion Criteria:

• significant chromosomal/congenital anomalies
• hemodynamically significant congenital heart disease (arrhythmia requiring medication, defects with chronic hypoxia, single ventricle physiology, heart failure)
• any child within 3 weeks of a respiratory tract infection, an asthma attack, an episode of ACS or of a vaso-occlusive or hemolytic crisis.