Vaso-occlusion in children with sickle cell disease: clinical characteristics and biologic correlates.

Vaso-occlusive pain is a frequent manifestation of sickle cell disease, but most clinical studies have documented only those pain episodes for which patients seek acute care or require hospitalization. Based on limited previous studies, the authors suggest that pain episodes managed at home are more frequent then those resulting in acute care management but likely share a common pathophysiology. The authors determined the characteristics of vaso-occlusive pain managed at home in 30 subjects (ages 6-19 years) using a self-report diary daily for 6 months. A total of 175 pain episodes were reported in 4,885 days, with 51% lasting 1 day or less. Severe pain, rated as 7 to 10 on a 10-point scale, was reported on 12% of pain days, but most pain was of mild to moderate intensity. A combination of baseline hematologic parameters and biomarkers assessing erythrocyte/endothelial cell adhesion, including hematocrit, fetal hemoglobin, and adhesion ratio, were statistically significant predictors of pain frequency in statistical analyses. Given the overlap in clinical features and predictive hematologic parameters of home-managed and acute care-managed pain, both likely represent a continuum of frequency and severity rather than distinct clinical entities. The higher frequency of these home-managed episodes suggests their potential utility as additional outcome measures in studies of vaso-occlusive pain.