RED BLOOD CELL RED BLOOD CELL VARIATION & VARIATION & PATHOLOGYPATHOLOGY

JOSE R.VILLARINO, RMTJOSE R.VILLARINO, RMT

RBC VariationRBC Variation

ANISOCYTOSISANISOCYTOSIS – variation in RBC size – variation in RBC size

Normocyte = measures 6.2 – 8.2 u Normocyte = measures 6.2 – 8.2 u (7.2 u)(7.2 u)

Microcyte = less than 6 uMicrocyte = less than 6 uMacrocyte = measuring 8 – 9 uMacrocyte = measuring 8 – 9 uMegalocyte = measures 9 – 12 uMegalocyte = measures 9 – 12 u

RBC Variation = colorRBC Variation = colorNormochromic – peripheral ring of Normochromic – peripheral ring of

Hgb surrounding an area of pallorHgb surrounding an area of pallorHypochromic – thin peripheral Hgb Hypochromic – thin peripheral Hgb

ring with an enlarged area of pallorring with an enlarged area of pallorEx. AnnulocyteEx. AnnulocyteHyperchromic – RBC appears thicker Hyperchromic – RBC appears thicker

than normal, stains evenly through than normal, stains evenly through out the cell and lacks the area of out the cell and lacks the area of pallor.pallor.

Ex. SpherocyteEx. Spherocyte

RBC Variation - colorRBC Variation - color

Anisochromia / dimorphic anemia – Anisochromia / dimorphic anemia – blood picture showing both blood picture showing both normochromic and hypochromic red normochromic and hypochromic red blood cells.blood cells.

Ex. Sideroblastic anemia, blood Ex. Sideroblastic anemia, blood transfusion and on Iron therapytransfusion and on Iron therapy

Polychromasia / polychromatophilia – a Polychromasia / polychromatophilia – a bluish gray color of the RBC on Wright’s bluish gray color of the RBC on Wright’s stain smear due to presence of RNA.stain smear due to presence of RNA.

Residual RNA indicates immaturity of Residual RNA indicates immaturity of cellcell

On supravital staining with Brilliant On supravital staining with Brilliant Cresyl Blue or New Methylene Blue, the Cresyl Blue or New Methylene Blue, the RNA combines with the stain to form the RNA combines with the stain to form the dye-ribonuceloprotein complex which dye-ribonuceloprotein complex which appears as a lacework pattern called the appears as a lacework pattern called the reticulum and thus calling the said cell reticulum and thus calling the said cell as RETICULOCYTE.as RETICULOCYTE.

Polychromasia = ReticulocytePolychromasia = Reticulocyte

Target cell – also called the leptocyte Target cell – also called the leptocyte ,the Mexican hat cell or the codocyte,the Mexican hat cell or the codocyte

An RBC with a peripheral ring of Hgb An RBC with a peripheral ring of Hgb plus a central condensation of Hgb in plus a central condensation of Hgb in the area of pallor or “ bull’s eye the area of pallor or “ bull’s eye appearance “appearance “

Found in patients with Found in patients with hemoglobinopathy and thalassemiashemoglobinopathy and thalassemias

RBC Variation in Shape - RBC Variation in Shape - PoikilocytosisPoikilocytosis

Secondary to Developmental MacrocytosisSecondary to Developmental MacrocytosisSecondary to Membrane AbnormalitiesSecondary to Membrane Abnormalities- Spherocyte- Spherocyte – small, spherical or rounded – small, spherical or rounded

shape RBC. They appear thicker than Nshape RBC. They appear thicker than No o

and are hyperchromic with increase and are hyperchromic with increase osmotic fragility.osmotic fragility.

- Echinocyte - Echinocyte – crenated RBC, small rbc with – crenated RBC, small rbc with uniformly sized, blunt projections evenly uniformly sized, blunt projections evenly distributed. Artifactual due to hypertonic distributed. Artifactual due to hypertonic solutions or excessive air drying of smearssolutions or excessive air drying of smears

Poikilocytosis – membrane Poikilocytosis – membrane abnormalityabnormality

- Burr cell- Burr cell – RBC with unevenly spaced – RBC with unevenly spaced spicules, more pointed rather than bluntspicules, more pointed rather than blunt

- Acanthocyte- Acanthocyte – spur cell, RBC with club- – spur cell, RBC with club-shaped (swollen) spicules, or prominent shaped (swollen) spicules, or prominent irregular thorn-like projectionsirregular thorn-like projections

- Stomatocyte- Stomatocyte – slit-shaped or mouth-like – slit-shaped or mouth-like areas of pallor. On wet mounts, appear to areas of pallor. On wet mounts, appear to be uniconcave or “rice-bowl” appearancebe uniconcave or “rice-bowl” appearance

Poikilocytosis – membrane Poikilocytosis – membrane abnormalityabnormality

- - CodocyteCodocyte – target cell, codocyte, – target cell, codocyte, Mexican hat cell or “ bulls-eye Mexican hat cell or “ bulls-eye appearance”appearance”

- - Ovalocyte Ovalocyte – also called elliptocyte, rbc – also called elliptocyte, rbc with cigar, oval or elliptical shapes.True with cigar, oval or elliptical shapes.True ovalocytes are to be distinguished from ovalocytes are to be distinguished from pseudoelliptocytes where true pseudoelliptocytes where true ovalocytes arranged at random order. ovalocytes arranged at random order. Pseudo follow one uniform direction Pseudo follow one uniform direction usually due to poor smear preparation.usually due to poor smear preparation.

Poikilocytosis – due to traumaPoikilocytosis – due to trauma

- Schistocyte- Schistocyte or or schizocyteschizocyte – fragments – fragments of destroyed RBC indicating trauma of destroyed RBC indicating trauma or a hemolytic processor a hemolytic process

- Keratocyte- Keratocyte – RBCs with horn-like – RBCs with horn-like projections, also called helmit cellsprojections, also called helmit cells

- Dacryocyte- Dacryocyte – teardrop looking RBCs , – teardrop looking RBCs , they appear swollen , pear-shapedthey appear swollen , pear-shaped

- Semi-lunar bodies- Semi-lunar bodies – pale pink, – pale pink, crescent shaped RBCs ( ghost cells )crescent shaped RBCs ( ghost cells )

Poikilocytosis – abnormal Hgb Poikilocytosis – abnormal Hgb contentcontent

- - Sickle cellSickle cell – depranocyte or – depranocyte or meniscocyte sickle-shaped or meniscocyte sickle-shaped or crescent-shaped RBC. The abnormal crescent-shaped RBC. The abnormal Hgb S during decreased oxygen Hgb S during decreased oxygen tension will crystallize or polymerize tension will crystallize or polymerize causing the cell to sickle shapecausing the cell to sickle shape

- - Hgb CC crystalsHgb CC crystals – hexagonal shaped – hexagonal shaped crystals with blunt endscrystals with blunt ends

- - Hgb SC crystalsHgb SC crystals – “ Washington – “ Washington monument appearance of crystals”monument appearance of crystals”

RBC InclusionsRBC Inclusions

Developmental OrganellesDevelopmental Organelles

- Howell Jolly bodies- Howell Jolly bodies – single blue bodies, – single blue bodies, DNA remnants. Seen in Pernicious anemiaDNA remnants. Seen in Pernicious anemia

- Basophilic stipplings- Basophilic stipplings also known as also known as punctuate basophiliapunctuate basophilia – fine to coarse, blue – fine to coarse, blue to purple granules scattered to purple granules scattered homogenously in the cytoplasm. homogenously in the cytoplasm. Remnants of ribosomal RNA and indicates Remnants of ribosomal RNA and indicates disturbed erythropoiesis.disturbed erythropoiesis.

RBC inclusionsRBC inclusions- Pappenheimer bodies- Pappenheimer bodies or or siderotic siderotic

granulesgranules iron containing granules that iron containing granules that appear dark-staining on Wright’s stain appear dark-staining on Wright’s stain found lying on the periphery of the cell found lying on the periphery of the cell in groups. On Perl’s Prussian Blue stain, in groups. On Perl’s Prussian Blue stain, these bodies stained positively these bodies stained positively indicating iron content.indicating iron content.

- Cabot rings- Cabot rings – ring-like, loop-like, figure of – ring-like, loop-like, figure of 8 staining reddish violet in Wright’s 8 staining reddish violet in Wright’s stain. Remnants of mitotic spindle or stain. Remnants of mitotic spindle or fragment of the nuclear membrane.fragment of the nuclear membrane.

Abnormal Hemoglobin Abnormal Hemoglobin PrecipitationPrecipitation

- - Heinz bodiesHeinz bodies – dense, highly refractile – dense, highly refractile granules representing precipitated granules representing precipitated or denatured globin associated with or denatured globin associated with the unstable Hgb. Seen in patients the unstable Hgb. Seen in patients with Glucose 6 Phosphate with Glucose 6 Phosphate dehyrogenase (G6PD) deficiencydehyrogenase (G6PD) deficiency

- Hemoglobin H inclusions- Hemoglobin H inclusions – greenish – greenish colored inclusions on BCB staining colored inclusions on BCB staining giving rise to the characteristic “golf-giving rise to the characteristic “golf-ball pattern”ball pattern”

RBC protozoan inclusionsRBC protozoan inclusions

- - Malarial parasitesMalarial parasites – presence of malarial – presence of malarial parasite stages ( ring forms, gametocytes parasite stages ( ring forms, gametocytes etc.) or pigments (stipplings) either on etc.) or pigments (stipplings) either on Wright’s or Giemsa stained smears.Wright’s or Giemsa stained smears.

- - Babesia microtiiBabesia microtii – like malaria, it is an – like malaria, it is an RBC infecting parasite though “tick-RBC infecting parasite though “tick-borne”. Only seen as ring forms in groups borne”. Only seen as ring forms in groups of 2 (rabbits ear) or 4 (Maltese cross of 2 (rabbits ear) or 4 (Maltese cross appearance)appearance)

Evaluation Guide to RBC Evaluation Guide to RBC VariationVariation

ANISOCYTOSIS = graded as +1 - +4ANISOCYTOSIS = graded as +1 - +4+1 = variation in size of more than 10% of +1 = variation in size of more than 10% of

the RBC /hpfthe RBC /hpfNORMOCYTOSIS = if less than 10% NORMOCYTOSIS = if less than 10%

variation notedvariation notedMACROCYTOSIS:MACROCYTOSIS:+1= approximately 25% macrocytes/hpf+1= approximately 25% macrocytes/hpf+2 - +3 = moderate >25-50% macrocytes+2 - +3 = moderate >25-50% macrocytes+4 = marked >50% macrocytes/hpf+4 = marked >50% macrocytes/hpf

Hypochromia Hypochromia

+1 = RBC shows an area of pallor +1 = RBC shows an area of pallor about 1/3-2/3 of cell diameterabout 1/3-2/3 of cell diameter

+2 - +3 = >2/3 of the cell diameter+2 - +3 = >2/3 of the cell diameter+4 = hgb staining seen only as a thin +4 = hgb staining seen only as a thin

rim of the peripheryrim of the peripheryPOIKILOCYTOSIS – Graded +1-+4 POIKILOCYTOSIS – Graded +1-+4

with Grade 1 if there is variation of with Grade 1 if there is variation of more than 10% of the RBC/hpfmore than 10% of the RBC/hpf

POLYCHROMATOPHILIAPOLYCHROMATOPHILIA

ALSO KNOWN AS ALSO KNOWN AS POLYCHROMATOPHILIAPOLYCHROMATOPHILIA

+1 – if 1-3 polychromatophilic cells +1 – if 1-3 polychromatophilic cells seen per microscopic fieldseen per microscopic field

+2 – if 3-5 cells seen+2 – if 3-5 cells seen+3 – more than 5 polychromatophilic +3 – more than 5 polychromatophilic

cells per mx fieldcells per mx field

Rouleaux formationRouleaux formation

Slight = 1-2 RBC chains noted/thin mx Slight = 1-2 RBC chains noted/thin mx fieldfield

Moderate = 3-4 RBC chains notedModerate = 3-4 RBC chains notedMarked = 5 or more chains noted.Marked = 5 or more chains noted.