1. Red Cell Morphology Basic Introduction Reference: Color Atlas of Hematology by Eric Glassy, M.D.

2. RBC Classification - - - - - - SIZE - - - - - - Normocyte Microcyte Macrocyte Anisocytosis - - - - - - SHAPE - - - - - - Acanthocytes Burr Cells Ovalocytes Tear Drops Stomatocytes Spherocytes Schistocytes Target Cells Sickle Cells - - - - - - PALLOR - - - - - - Normochromic Hypochromic Hyperchromic Polychromasia - - - - INCLUSIONS - - - - NRBC’s Howell-Jolly bodies Basophilic Stippling Pappenheimer bodies Hemoglobin crystals

3. RBC Parameters MCV = X 10 80 – 100 fL MCH = X 10 27 – 31 pg/cell MCHC = X 100 32 – 36 g/dL Hct_ RBC Hgb_ RBC Hgb_ Hct Microcytic 100 fL Hypochromic 36 g/dL

4. Normal RBC

5. Normal RBC 50x Objective

6. Normal RBC 100x Objective

7. Microcytes SYNONYMS: microcytic RBCs KEY FEATURES: –Size: MCV < 80 fL; diameter < 6  m –Cytoplasm: normochromic or often hypochromic with increased central pallor

8. Microcytic Compare RBC and Lymph sizes

9. Macrocytes SYNONYMS: macrocytic RBCs; macro-ovalocyte (oval form) KEY FEATURES: –Size: MCV > 100 fL; diameter > 8  m –Shape: round or oval –Cytoplasm: normochromic, but may sometimes be hypochromic; no polychromasia

10. Macrocytes Compare RBC and Lymph sizes

11. Anisocytosis Size Variation RDW Guide (g/dL) Slight = 16-20 Moderate = 20-26 Marked = > 26 Only use RDW as a guide

12. Hypochromia SYNONYMS: hypochromic RBCs KEY FEATURES: –Size: microcytic or macrocytic cells –Cytoplasm: central pallor > 1/3 of RBC diameter (increased central pallor); some cells contain so little hemoglobin that they are “ghost cells”

13. Microcytic – Hypochromic Compare RBC and Lymph sizes

14. Polychromasia SYNONYMS: polychromatophil; reticulocyte (presumptive) KEY FEATURES: –size: slightly larger than erythrocyte –shape: round to slightly oval –cytoplasm: little or no central pallor; color is slightly more gray-blue or purple than that of an erythrocyte

15. Polychromic

16. Acanthocytes SYNONYMS: spur, spike or horn cell APPEARANCE: Crenated RBC with very spiny, irregular projections KEY FEATURES: –Size: diameter smaller than normal cells (like spherocytes) –Shape: 3 – 20 irregular membrane spikes, unevenly distributed –Cytoplasm: no central pallor

17. Acanthocytes

18. Burr Cells SYNONYMS: Echinocyte, crenated cell APPEARANCE: Similar to crenated RBCs but projections are less pointed and more regular than acanthocytes KEY FEATURES: –Size: normocytic –Shape: 10-30 evenly distributed short, blunt or pointed spicules; projections uniformly sized –Cytoplasm: normochromic; retains central pallor (unlike acanthocytes)

19. Burr Cells

20. Elliptocytes SYNONYMS: ovalocyte, pencil cell APPEARANCE: elongate with round ends (cigar, egg, pencil shapes) KEY FEATURES: –Size: variable; usually longer than normal red cell and much more narrow –Shape: uniform, symmetrical rod shape; sides nearly parallel –Cytoplasm: often retain central pallor

21. Elliptocytes

22. Teardrop Cells SYNONYMS: dacrycocyte APPEARANCE: Round cells with elongated tail or point; resembles a teardrop KEY FEATURES: –Size: microcytic to normocytic –Shape: teardrop or pear-shaped RBC with single tapered end (tail) that is blunt or round –Cytoplasm: normochromic to hypochromic

23. Teardrop Cells

24. Stomatocytes SYNONYMS: hydrocyte APPEARANCE: RBC with a slit-like central pallor KEY FEATURES: –Size: normocytic –Shape: round; uniconcave disc –Cytoplasm: normochromic; central pallor appears slit-like, straight, fish­mouth, or curved rod-shaped; a few cells may have tri-polar pallor creating cells that resemble sleigh bells

25. Stomatocytes

26. Spherocytes SYNONYMS: none APPEARANCE: Cells appear perfectly round and have no central pallor; often smaller than normal RBCs KEY FEATURES: –Size: slightly microcytic –Shape: round to spherical –Cytoplasm: no central pallor

27. Spherocytes 50x Objective

28. Spherocyte 100x Objective

29. Schistocytes SYNONYMS: helmet cell, triangulocyte, keratocyte, horn cell, fragmented RBCs APPEARANCE: Pieces of RBCs that can have a vast variety of shapes and sizes KEY FEATURES: –Size: irregular cell sizes; usually microcytic –Shape: shapes vary from helmet to triangular to unclassified fragments –Cytoplasm: small fragments lack central pallor; horn cells can be normochromic

30. Schistocytes Fragmented RBCs

31. Target Cells SYNONYMS: codocyte APPEARANCE: RBCs have a bullseye appearance KEY FEATURES: –Size: normocytic to slightly macrocytic –Shape: round –Cytoplasm: increased surface membrane to volume ratio results in a central, darker hemoglobin region within the area of central pallor creating the appearance of a target or bullseye

32. Target Cells

33. Sickle Cells SYNONYMS: drepanocyte APPEARANCE: Usually a thin, crescent shaped cell KEY FEATURES: –Shape: sickle shaped with at least one pointed end; may also be crescent-shaped, boat- shaped, filament shaped, holly-leaf form (rarely) and envelope shaped –Cytoplasm: no central pallor; very dense hemoglobin concentration (normochromic to hyperchromic)

34. Sickle Cells 50x Objective

35. Sickle Cells 100x Objective

36. RBC Inclusions NRBCs Howell-Jolly Bodies Basophilic Stippling Pappenheimer Bodies Hemoglobin Crystals

37. Nucleated Red Blood Cells SYNONYMS: NRBCs APPEARANCE: RBC with a small, pyknotic nucleus with dense chromatin KEY FEATURES: –Size: 8-10  m size; slightly larger than a mature RBC –Cytoplasm: varies depending on stage of maturation; usually more blue-gray

38. NRBCs Nucleated RBC

39. NRBCs

40. Howell-Jolly Bodies SYNONYMS: nuclear fragment, HJ bodies, Ho-Jo’s APPEARANCE: Large, singular dark purple inclusion KEY FEATURES: –Size: 1  m; sometimes as small as 0.5  m –Shape: spherical or oblong blue-purple or blue-black inclusion –Cytoplasm: normochromic or hypochromic –Location: eccentrically located (off center); usually a single inclusion, but multiple can be present

41. Howell-Jolly Bodies Pappenheimer Bodies (Iron)

42. Basophilic Stippling SYNONYMS: punctuated basophilia APPEARANCE: Medium-sized, blue-black dots (granules) evenly distributed throughout the RBC KEY FEATURES: –Size of granules: numerous small coarse or fine granules; uniform in size and shape ;  0.5  m in diameter –Cytoplasm: uniformly filled with deep blue or blue-gray dots

43. Basophilic Stippling

44. Pappenheimer Bodies SYNONYMS: none APPEARANCE: Small dark blue-purple staining hemoglobin iron granules; seen on Wright stained smear and confirmed with iron (Prussian blue) stain KEY FEATURES: –Size: usually less than 1  m (sometimes <0.5  m) –Shape: blue-purple granules with irregular, sharp edges (not round) –Location: usually found along the periphery of the cell; one or two irregular, small blue- purple-green granules; if present in multiples, they form irregular closely aggregated clusters

45. Pappenheimer Bodies Wright Stain

46. Pappenheimer Bodies Iron Stain

47. Hemoglobin Crystals SYNONYMS: none APPEARANCE: dense staining, angular crystalline forms that vary in shape; may be rectangular, rod-shaped, tetragonal, octahedral (Washington monument, gold bar), spherocytic, rhomboid, or hexagonal KEY FEATURES: –Size: variable since crystals may markedly distort the cell –Shape: a normal disc shape is distorted by the crystal; cytoplasm contains the crystal, which is a precipitate of hemoglobin C or SC –Cytoplasm: often pale or colorless; there is generally a clear area around the crystal

48. Hemoglobin SC Crystals glove cells

49. Typical RBC Abnormal Morphology Polychromasia Acanthocyte Teardrop Schistocyte Microcyte Spherocyte Burr Cell Elliptocyte Target Cell Hypochromic

50. Any Questions?