Erythrocytes Part 2 Ms. Nelson, lvt

Variations in Cell shape Poikilocytes Abnormally shaped erythrocytes are called poikilocytes. This term does NOT suggest why the RBC has a shape change, so no specific diagnosis can be determined. The term poikilocytosis should ONLY be used when the morphologic abnormalities cannot be described with more specific terms Poikilocytes are an umbrella term (if a RBC is abnormal shape it is called Poikilocytes). Each shape has its own name though. generic term for abnormally shaped RBC’s

Variations in cell shape Schistocytes Acanthocytes Echinocytes Drepanocytes Keratocytes Spherocytes Leptocytes Elliptocytes (Ovalocytes) Eccentrocytes Dacryocytes

Schistocytes Schistocytes RBC fragments. Usually formed as a result of the shearing of the RBC via intravascular trauma Can be seen in: patients with: DIC (disseminated intravascular coagulopathy), hemangiosarcoma, iron deficiency DIC, the body is unable to clot normally (causes could be heat stroke, pancreatitis. Cancer) Hemangiosarcoma is cancer of the vascular endothelium, or the blood vessel walls. Hemangiosarcoma of the spleen or liver is the most common tumor to cause hemorrhage in the abdomen

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Acanthocytes (spur cells) May also be called spur cells Irregular, speculated RBCs with a few unevenly distributed surface projections of variable length and diameter. Can be seen in: Patients with altered lipid metabolism (due to liver involvement), older or large breed animals with regenerative anemia that suggests hemangiosarcoma Cats with hepatic lipidosis or dogs with hemangiosarcoma of the liver In a regenerative anemia, the bone marrow responds appropriately to the decreased number of red blood cells by increasing production of new blood cells (could see with auto-immune diseases or cancer)

Acanthocytes (Spur Cells), continued…

Acanthocytes, continued…

Echinocytes (Burr Cells) Spiculated cells with numerous short, evenly spaced, blunt to sharp surface projections of uniform size and shape. The common term for this abnormality is crenation. These can be seen as artifacts, when you slow dry blood films, or store the sample for extended periods of time If you under fill an EDTA tube, you can see echinocytes as artifacts Can be seen in: Patients with renal disease, lymphosarcoma in dogs, after exercise in horses, samples from normal healthy pigs, also seen after viper envenomation in dogs. Thinner blood slides dry quicker because they aren’t as thick. Lavender-top tube: EDTA is a anticoagulant EDTA: Ethylenediaminetetraacetic acid Partially filled EDTA tubes affect the cells because EDTA is hypertonic (echinocytes will form in underfilled EDTA tubes because the red cells shrink) Hypertonic: higher osmotic pressure so if not filled enough it will shrink and change the shape of the red blood cell Lymphosarcoma: cancer of the lymphocytes (a type of blood cell) and lymphoid tissues

Echinocytes (Burr Cells), continued…

Echinocytes (Burr Cells), continued…

Drepanocytes (sickle cells) Also called sickle cells Observed in the blood of normal deer and angora goats. Thought to be an in vitro phenomenon that is caused by high oxygen tension

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Keratocytes (Helmet, Blister, Bite cells) Commonly referred to as helmet cells, blister cells, or bite cells The cell may appear to contain a vacuole Believed to be formed by intravascular trauma that involves the bisection of the cell by fibrin strands, the opposing sides of the cell adhere to each other and form this pseudovacuole. May be seen in: Patients with anemia, liver disorders, myelodysplastic syndrome (leukemia) fibrous, non-globular protein involved in the clotting of blood Myelodysplastic syndromes (MDS) are a group of cancers in which immature blood cells in the bone marrow do not mature and therefore do not become healthy blood cells

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Spherocytes Spherocytes Darkly staining RBC’s with reduced or no central pallor Not easily detected in species other than dogs. Though they have a decreased diameter and appear small, their volume is normal. They have a reduced amount of membrane surface areas a result of partial phagocytosis by macrophages, which occurs as a result of the presence of antibodies on the surface of the RBC. May be seen in: Transfusion patients that received mismatched or improperly stored blood, after snake envenomation, RBC parasites, zinc toxicity, and AIHA Because dogs have such a distinct central pallor These usually suggest immune-mediated destruction of RBC’s (Autoimmune hemolytic anemia): It happens when the body produces antibodies that destroy the red blood cells

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Leptocytes (Target cells, codocytes) Characterized by an increased membrane surface area relative to cell volume. Affected cells may take on a variety of shapes. Also referred to as target cells and codocytes May be seen in: Patients with anemia, liver diseases and some inherited disorders One of the variety of shapes is a folded cell They have a central area of pigment surrounded by a clear area

Leptocytes, continued…

Leptocytes, continued…

Stomatocytes (folded cells) These have a transverse, raised fold that extends across the center of the cell as well as a clear, slit like pale region in the center of the cell. Can be considered artifact if the areas of pallor are all perpendicular to the feathered edge on a smear Can be seen in liver disease/alcohol toxicity

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Elliptocytes (Ovalocytes) Can be normal in camelid species and nonmammals. In other species, these cells are associated with lymphoblastic leukemia, hepatic lipidosis, portosystemic shunts, and glomerulonephritis Camel family lymphoblastic leukemia (ALL) is a type of cancer in which the bone marrow makes too many lymphocytes

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Eccentrocytes Eccentrocytes Have been seen in patients with diabetic ketoacidosis or neoplasia, with Babesia canis infections, and after ingestion of oxidants such as garlic, onions, and acetaminophen. The hemoglobin is primarily pushed to the side Toxic doses of garlic can cause damage to the red blood cells (making them more likely to rupture) leading to anemia Too many onions consumed destroy a dog's red blood cells, leaving dogs without enough of them for healthy functioning

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Dacryocytes Dacryocytes Appear as teardrop shaped cells. Can be artifacts, if all the tails are pointing in the same direction Seen in patients with myelofibrosis and certain myeloproliferative diseases. Have also been discovered in llamas and alpacas that are iron deficient. Myelofibrosis is an uncommon type of bone marrow cancer that disrupts your body's normal production of blood cells Myeloproliferative disorders are a group of slow-growing blood cancers in which the bone marrow makes too many abnormal red blood cells , white blood cells , or platelets , which accumulate in the blood

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Inclusions In RBC’s Inclusion: the action or state of including or of being included within a group or structure (stuff inside the RBC’s)

Nucleated Erythrocytes (nRBC) RBC Inclusions Basophilic Stippling Howell-Jolly Bodies Heinz Bodies Nucleated Erythrocytes (nRBC)

Basophilic Stippling Basophilic Stippling The presence of small, dark blue bodies within the erythrocyte Observed in Wright stained cells and represents residual RNA Common in immature RBCs of ruminants and occasionally in those of cats during a response to anemia Also seen in lead poisoning RNA: genetic formation

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Howell-Jolly Bodies Howell-Jolly bodies Basophilic nuclear remnants that are seen in young RBCs during the response to anemia As they pass through the spleen, phagocytic cells remove the remnants If there is splenic disorders or removal of the spleen, you may see an increased number of these inclusions Basophilic nuclear remnants : clusters of DNA Cells that contain nuclear remnants pass through the liver and phagocytic cells remove them, that is why you will see them after a splenectomy

Howell-Jolly Bodies, continued…

Howell-Jolly Bodies, continued…

Heinz Bodies Heinz Bodies Round bodies that represent denatured hemoglobin and are caused by certain oxidant drugs or chemicals The denatured hemoglobin becomes attached to the cell membrane and appears as a pale area with Wright's stain. When stained with new methylene blue, the Heinz bodies appear blue. Normal cats can have Heinz bodies in as many as 5% of their RBC’s, but in other animals an increased concentration of them can be seen with lymphosarcoma, hyperthyroidism and diabetes mellitus in cats. Oxidizing: combine or become combined chemically with oxygen

Heinz bodies, continued…

Heinz bodies, continued…

Nucleated Erythrocytes (nRBC) Represent the early release of immature cells during anemia. May be occasionally observed in nonanemic animals. All RBCs of nonmammalian species (birds, reptiles) contain nuclei.

Occasionally parasites can be seen in blood smears Parasites in RBC’s Occasionally parasites can be seen in blood smears The most commonly seen are Ehrlichia and Mycoplasma, and occasionally Dirofilaria immitis Other parasites that may make an appearance Eperythrozoa Anaplasma Cytauxzoon Babesia Eperythrozoa: bacteria Anaplasma: bacteria, spread by the black legged tick Cytauxzoon: a protozoal organism transmitted to domestic cats by tick bites Babesia is a tiny parasite that infects your red blood cells (spread by a tick)

Parasites in RBC’s, continued… Babesia

Parasites in RBC’s, continued… Dirofilaria immitis microfilaria