Acute Painful Crises of Sickle Cell Disease in Egyptian Children: Predictors of Severity for a Preventive Strategy

The objective of this study was to predict which infants with sickle cell disease (SCD) are prone to develop severe painful crises. In a mixed hospital - and community-based population (76 cases), demographic data, SCD diagnostic parameters, and basal blood counts were correlated with 2 indices of SCD severity: pain rate (average number of days of painful episodes per year of follow-up) and serious life-threatening complications, such as hyperhemolytic crises. Data were analyzed blind to these indices. The Student t test, analysis of variance, and Pearson correlation were used to determine association with pain rate. Discriminant analysis was used for the prediction of SCD severity. Pain rate was significantly high in hemoglobin SS patients, especially in those with an early onset of dactylitis. There were statistically significant negative correlations of pain rate with basal hemoglobin level, hematocrit, percent hemoglobin F, and arterial oxygen saturation (P <.01 for all correlations). The top 3 predictors of SCD severity were (in descending order) genotype, basal hemoglobin level, and early dactylitis. Severe forms of SCD could be predicted in early infancy with 100% accuracy by using the basal diagnostic parameters for the disease. These infants should be closely monitored with special attention to ventilation status, even before the development of dactylitis.