Consensus criteria at St Jude Children's Research Hospital for initiating hydroxyurea treatment for children and adolescents with SCA (around January 2010)
| Consensus for HbSS or HbS/β0-thalassemia, age ≥ 24 mo |
| Pain including dactylitis |
| ACS |
| Low hemoglobin, percentage HbF |
| Elevated WBC, LDH |
| Chronic hypoxemia |
| Abnormal TCD values refusing transfusions |
| No clear consensus, to be discussed case by case |
| Conditional TCD velocities |
| Abnormal brain MRI (eg, silent infarcts) |
| Neurocognitive decline |
| Age < 24 mo |
| Poor growth and development |
| HbSC genotype |
| Parental request |
| Consensus for HbSS or HbS/β0-thalassemia, age ≥ 24 mo |
| Pain including dactylitis |
| ACS |
| Low hemoglobin, percentage HbF |
| Elevated WBC, LDH |
| Chronic hypoxemia |
| Abnormal TCD values refusing transfusions |
| No clear consensus, to be discussed case by case |
| Conditional TCD velocities |
| Abnormal brain MRI (eg, silent infarcts) |
| Neurocognitive decline |
| Age < 24 mo |
| Poor growth and development |
| HbSC genotype |
| Parental request |
SCA indicates sickle cell anemia; ACS, acute chest syndrome; HbF, fetal hemoglobin; WBC, white blood cell; LDH, lactate dehydrogenase; TCD, transcranial Doppler; and MRI, magnetic resonance imaging.