Blood/Blood Cells and Cellular Components ›› Red Blood Cells ›› Abnormal Sickle Cell* Click Here for Full Size › Microscopic Features: About the same size as a normal RBC Banana-shpaed RBC with two pointed ends Usually forming the shape of a crescent or banana Dense hemoglobin (dark red to light purple) No central pallor › Normal % blood-PB, marrow-BM, lymphoid tissue-LN: PB: None BM: None LN: None › May Resemble: Schistocyte Ovalocyte (elliptocyte) Hemoglobin C crystals Malaria organisms (gametes outside of RBCs) › Differential Diagnoses: Hemoglobin SS disease Hemoglobin SC disease Hemoglobin SD disease S-beta thalassemia › Classic Immunophenotype: N/A › Cartoon Image: Click and drag for direct comparison › Misc: An underlying mutation in the hemoglobin Beta chain (The hydrophilic residue Glutamate is replaced with the hydrophobic residue Valine) which leads to aggregation of the hemoglobin molecules which ultimately twists the RBC into a sickled shape