The reversibly sickled cell

PURPOSE: We have developed and applied simple techniques for the detection of irreversibly and reversibly sickled cells (ISCs and RSCs) in blood samples. Both ISCs and RSCs are found in the venous and arterial circulation, and sickling and unsickling occurs continuously in the tissues and arterial blood, respectively. PATIENTS AND METHODS: Using these techniques, we have studied the number of RSCs and ISCs in 100 children with sickle cell disease (SS) and 20 with sickle cell C disease (SC). RESULTS: Both RSC and ISC numbers were significantly higher in blood samples of children with SS than those with SC disease. The number of RSCs and ISCs bears a direct relationship to the severity of the hemolytic process but has a negative relationship to the frequency of vaso-occlusive crises. CONCLUSIONS: The manifestations of sickle cell disease appear not to be the result of large numbers of circulating sickled cells randomly lodging in vessels but more likely are the result of local vascular stasis with subsequent sickling and vaso-occlusion.