Blood rheological abnormalities in sickle cell anemia

Area of Science:

• Hematology
• Pathophysiology
• Vascular Biology

Background:

• Sickle cell anemia (SCA) involves heterogeneous red blood cell (RBC) deformability.
• Abnormal blood rheology is a key factor in SCA pathophysiology.
• RBC aggregation and vascular reactivity are altered in SCA patients.

Purpose of the Study:

• To review the role of abnormal blood rheology in SCA pathophysiology.
• To correlate RBC deformability and aggregation with SCA complications.
• To examine the impact of blood viscosity on vaso-occlusive crises.

Main Methods:

• Literature review of studies on SCA blood rheology.
• Analysis of ektacytometry data for RBC deformability.
• Examination of studies on RBC aggregation and vascular reactivity.

Main Results:

• Lowest RBC deformability correlates with hemolysis and complications (priapism, leg ulcers, glomerulopathy).
• Highest RBC deformability (without hydroxyurea) is linked to vaso-occlusive events.
• Increased RBC aggregate strength and impaired vascular reactivity contribute to viscosity and crises.

Conclusions:

• Blood rheology significantly influences SCA pathophysiology and complication development.
• RBC deformability and aggregation are critical determinants of SCA severity.
• Altered vascular compensation mechanisms exacerbate vaso-occlusive crises in SCA.