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URL of this page: //medlineplus.gov/ency/imagepages/1494.htm
Red blood cells - sickle cells
Overview
These crescent or sickle-shaped red blood cells (RBCs) are present with Sickle cell anemia, and stand out clearly against the normal round RBCs. These abnormally shaped cells may become entangled and block blood flow in the small blood vessels (capillaries).
Review Date 2/27/2026
Updated by: Jacob Berman, MD, MPH, Associate Professor of Medicine, Division of General Internal Medicine, University of Washington School of Medicine, Seattle, WA. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.