Blood Cell Identification Graded

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1 Blood Cell Identification Graded Case History The patient was a five-day-old girl with an elevated unconjugated bilirubin and a weakly positive direct antiglobulin test (DAT). Her CBC showed: WBC = 11.0 x 10 9 /L; HGB = 12.8 g/dl; and PLT = 184 x 10 9 /L. The patient s blood type was A, Rh positive and her mother s was O, Rh positive. Her mother s antibody screen was negative. /-21 Nucleated red cell, normal or abnormal morphology (blood only) Good This was correctly identified as a nucleated red cell by 100.0% of the referees and 99.7% of the participants. The terminology used, nucleated red cell, includes all normoblasts in peripheral blood circulation regardless of the stage of maturation. The presence of nucleated red cells in the blood may be the consequence of a bone marrow stress reaction. However, frequently it is the manifestation of a specific pathologic condition like myelofibrosis, thalassemia, myeloproliferative disorders or hemolytic anemias. In this situation there is an immune mediated hemolysis secondary to the mother s anti-a reacting with the newborn s A positive red cells. 2

2 Blood Cell Identification Graded /-22 Basophil, any stage Good This was correctly identified as a basophil by 100.0% of the referees and 98.7% of the participants. Basophils are characterized by their specific granules and follow a maturation sequence that is analogous to the neutrophil cell line. They are usually present in low numbers in the peripheral blood. Conditions associated with an increased number of basophils include hypothyroidism with myxedema, hypersensitivity reactions and myeloproliferative disorders. 3

3 Blood Cell Identification Graded /-23 Fragmented cell (schistocyte, Good helmet cell, keratocyte) Stomatocyte Unacceptable This was identified correctly as a fragmented red cell by 94.0% of the referees and 99.1% of the participants. Fragmented red cells are a group of poikilocytes that share in common an irregular red cell shape. Included in this group are helmet cells, schistocytes, keratocytes and just plain red cells fragments (with or without central pallor). In general, when these poikilocytes are present in increased numbers they signal the presence of a clinically significant condition like microangiopathic anemia, thrombotic thrombocytopenic purpura (TTP), disseminated intravascular coagulation (DIC), hemolytic uremic syndrome (HUS) and malignant hypertension. 4

4 Blood Cell Identification Graded /-24 Howell Jolly Body Good Howell Jolly body was correctly identified by 100.0% of the referees and 98.9% of the participants. Howell Jolly bodies are small round red cell inclusions made of DNA. They are characteristically seen in individuals with absent or non functioning spleens, as the spleen usually removes these inclusions from red cells. Howell Jolly bodies are also seen in severe hemolytic anemias and megaloblastic anemias. Occasionally they are also recognized in normal individuals. 5

5 Blood Cell Identification Graded /-25 Spherocyte Good This was correctly identified by 100.0% of the referees and 99.5% of the participants. Spherocytes are abnormal, small, round, thicker than normal red cells that are also characterized by the absence of central pallor. They characteristically come about as a consequence of a loss of red cell membrane. When the surface membrane has been pulled out, the red cell becomes smaller and loses volume and plasticity. Consequently, the spherocyte is described as a rigid red cell as it cannot deform well enough to travel its way through small diameter capillaries. Spherocytes are then removed from circulation usually long before the normal 120 day life span. An increased number of spherocytes is typically seen with congenital spherocytosis and immune hemolytic anemias (Coombs positive anemias). 6

6 Blood Cell Identification Ungraded Case History This peripheral blood smear is from a 73-year-old man with a history of stage IV mycosis fungoides who presents with leukocytosis and recent progression of his tumors. Laboratory data includes: WBC = 25.6 x 10 9 /L; RBC = 4.34 x /L; HGB = 12.5 g/dl; HCT = 39.5%; MCV = 91 fl; and PLT = 413 x 10 9 /L. /-26 Lymphoma cell Educational Lymphocyte Educational Lymphocyte, reactive Educational The arrowed cell is an abnormal lymphocyte which in this case represents a lymphoma cell. The lymphoma cell was correctly identified by 100.0% of the referees and 82.1% of the participants. The lymphoma cell is larger than a normal lymphocyte, contains a nucleus with condensed chromatin and several delicate folds in the nuclear membrane that create convolutions within the nucleus. Because the convolutions within the nucleus resemble the normal brain surface, this type of lymphoma cell is often described as cerebriform and in this case represents a Sezary cell. A lymphoma cell is present in all of the images provided for this case (- 26, 27, 28, 29, 30); -27 contains 2 lymphoma cells. All the lymphoma cells display convoluted nuclei, but the degree of the nuclear irregularity is variable among the lymphoma cells. 7

7 Blood Cell Identification Ungraded /-27 Polychromatophilic (nonnucleated) red cell Educational The arrowed cells are polychromatophilic red blood cells (RBC) which lack a central pallor and are larger and darker than the mature RBCs. Polychromatophilic RBCs are the youngest RBCs released from the marrow into the circulation. The basophilic staining is due to the ribonucleic acid (RNA) present in the cell. A supravital stain highlights the RNA allowing identification of these polychromatophilic RBCs as reticulocytes. These polychromatophilic cells were correctly identified by 100.0% of the referees and 99.1% of the participants. Two lymphoma cells are present in this image. The irregular nuclear outlines are particularly exaggerated in these lymphoma cells. In fact, the nucleus of the lymphoma which is at the edge of the image resembles a clover leaf. 8

8 Blood Cell Identification Ungraded /-28 Platelet, normal Educational Platelet, giant Educational (macrothrombocyte) The arrowed cell is a normal platelet which was correctly identified by 100.0% of the referees and 77.8% of the participants. The shape of a normal platelet is variable and this is usually evident in the platelets in the blood smear. Generally, a normal platelet is smaller than a RBC, is round or oval, and contains azurophilic granules within the granulomere as well as a region without granules known as the halomere. A small amount of halomere is visible in this case. This platelet is not a giant platelet as this term is reseved for platelets that are larger than the size of the average red blood cell in the field assuming a normal MCV. 9

9 Blood Cell Identification Ungraded /-29 Monocyte Educational The arrowed cell is a normal, mature monocyte which was correctly identified by 100.0% of the referees and 97.0% of the participants. Monocytes show variable morphology which may make them difficult to identify in some circumstances. However, generally the normal monocyte is slightly larger than a neutrophil. The cytoplasm is abundant, often contains variable numbers of small azurophilic granules and may also contain vacuoles. The cytoplasm is typically blue/gray but is quite variable depending on the quality of the Wright-Giemsa staining. The nucleus is large and indented or folded with condensed chromatin and does not contain a nucleolus. A lymphoma cell is also present in the image. This lymphoma cell is smaller than the monocyte, has much less cytoplasm and the chromatin is much more condensed. 10

10 Blood Cell Identification Ungraded /-30 Neutrophil, segmented or Educational band Neutrophil, toxic Educational Eosinophil, any stage Educational The arrowed cell is a neutrophil. The nucleus is segmented, and contains at least 3 visible lobes which are connected by thin bands of chromatin. The cytoplasm of the neutrophil comprises approximately 1/3 of the cell size and contains many secondary granules. A few of the granules appear more azurophilic which is most likely due to a staining artifact. However, as mild toxic granulation cannot be entirely excluded, a toxic neutrophil must also be considered correct in the interpretation of this case. One hundred percent of the referees and 91.0% of the participants provided a correct response. The lymphoma cell illustrated in this image contains small vacuoles in the cytoplasm and a large nucleolus is visible within the nucleus. 11