Blood Cell Identification Graded

1 2 Blood Cell Identification Graded Case History This peripheral Blood smear is from a 51-year-old female who had a prior splenectomy for a 30-year history of polycythemia vera. A routine CBC showed a significant change in Blood counts from previous exams. Laboratory data include: WBC = x 109/L; RBC = x 1012/L; HGB = g/dL; HCT = ; MCV = 88 fL; RDW = ; PLT = 25 x 109/L. BCP-11 Referees Participants Identification No. % No. % Evaluation Blast cell 80 4602 Good Lymphocyte, reactive (to include plasmacytoid and immunoblastic forms) 3 223 Unacceptable Prolymphocyte 2 128 Unacceptable Monocyte, immature (promonocyte, monoblast) 1 78 Unacceptable The arrowed cell is a blast and was correctly identified by of referees and of participants. The blast is large in size when contrasted with the surrounding erythrocytes, and has a moderate amount of basophilic and agranular cytoplasm with a high N:C ratio.

2 The chromatin is fine and delicate with two prominent nucleoli. 3 Blood Cell Identification Graded BCP-12 Referees Participants Identification No. % No. % Evaluation Platelet, giant 88 5328 Good The arrowed cells are giant platelets and were correctly identified by of referees and of participants. This cluster of platelets is comprised of giant, large, and normal-sized platelets. Abnormal platelets are a common feature in myeloproliferative neoplasms. 4 Blood Cell Identification Graded BCP-13 Referees Participants Identification No. % No. % Evaluation Platelet, normal 83 5174 Good Platelet, hypogranular 5 221 Unacceptable The arrowed cell is a platelet (thrombocyte) and was correctly identified by of referees and of participants. Platelets are small, blue-gray fragments of megakaryocytic cytoplasm containing fine, purple-red granules.

3 The arrowed normal sized platelet is in stark contrast to the giant platelet present in the center of the image which is adjacent to a blast. Giant and bizarre platelets are a common feature found in Blood smears from patients with myeloproliferative neoplasms. 5 Blood Cell Identification Graded BCP-14 Referees Participants Identification No. % No. % Evaluation Lymphocyte 88 5341 Good The arrowed cell is a lymphocyte and was correctly identified by of referees and of participants. A lymphocyte is a small, round to ovoid cell which may range in size from 7 to 15 m with variable N:C ratios. While most lymphocytes are small with round to oval nuclei, some normal lymphocytes are medium-sized due to an increased amount of cytoplasm. Chromatin is diffusely dense or coarse and clumped. Nucleoli, if present, are small and inconspicuous. The two other leukocytes in the field are blasts, similar to the blast arrowed in BCP-11.

4 The finding of frequent blasts in a patient with a myeloproliferative neoplasm is a clue to acceleration of disease, in this case to acute myeloid leukemia. 6 Blood Cell Identification Graded BCP-15 Referees Participants Identification No. % No. % Evaluation Basophil, any stage 86 5215 Good Neutrophil, toxic (to include toxic granulation and/or D hle bodies, and/or toxic vacuolization) 2 103 Unacceptable The arrowed cell is a basophil and was correctly identified by of referees and of participants. Basophils are characterized by large coarse cytoplasmic granules that are typically blue-black, but occasionally may be purple to red. The granules vary in size, are roughly spherical, and frequently overlay or even obscure the nucleus. The nucleus is lobated similar to a neutrophil. It is common for basophils to partially degranulated as shown in this image. Tracy I. George, MD, Chair Hematology and Clinical Microscopy Resource Committee 7 Blood Cell Identification Ungraded Case History This Blood film is from an 82-year-old male with fatigue, drenching sweats, recent weight loss, and large lymph nodes.

5 Laboratory data include: WBC = x 109/L; RBC = x 1012/L; HGB = g/dL; MCV = 112 fL; and PLT = 89 x 109/L. BCP-16 Referees Participants Identification No. % No. % Evaluation Prolymphocyte 35 1605 Educational Blast cell 25 1505 Educational Monocyte, immature (promonocyte, monoblast) 8 558 Educational Lymphoma cell (malignant), includes Hairy cell and Sezary cell 6 587 Educational Neutrophil, myelocyte 5 368 Educational Lymphocyte, reactive (to include plasmacytoid and immunoblastic forms) 3 165 Educational Monocyte 1 85 Educational Neutrophil, promyelocyte 1 122 Educational The white Blood cell identified by the arrow is a prolymphocyte, as correctly identified by of referees and of participants. Morphologically, prolymphocytes are round to oval in shape and have a centrally placed nucleus. The prolymphocyte nucleus contains condensed mature appearing chromatin with a single prominent nucleolus.

6 There tends to be a moderate amount of pale agranular cytoplasm that is more abundant than is typically seen in small lymphocytes or blasts but less than in reactive lymphocytes. Rarely, prolymphocytes may have more than one nucleolus and the nuclear contours may appear slightly irregular. One of the most helpful features for Identification of prolymphocytes in this case is the recognition of the typical CLL/SLL lymphocytes in the background, such as the cell in the upper left. Prolymphocytes usually comprise a small proportion of cells in patients with chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL); although an increasing prolymphocyte proportion can occur and represents progression of the patient s leukemia. If prolymphocytes account for more than 55% of lymphocytes, a diagnosis of prolymphocytic leukemia (PLL) is appropriate. It is important to distinguish prolymphocytes from other abnormal cells , such as blasts, lymphoma cells , and reactive lymphocytes (see educational discussion).

7 8 Blood Cell Identification Ungraded BCP-17 Referees Participants Performance Identification No. % No. % Evaluation Stomatocyte 86 5301 Educational The red Blood cell identified by the arrow is a stomatocyte, as correctly identified by of referees and of participants. A stomatocyte is similar in size, contour, and staining characteristics to a normal erythrocyte but in contrast to normal erythrocytes, the region of central pallor is slit-like, resembling a smiling face or fish mouth, rather than round. Stomatocytes are commonly seen with hereditary stomatocytosis, liver disease, and acute alcoholism; although a small number of stomatocytes may form as an artifact of slow drying of the Blood smear . Also of note in this image is a prolymphocyte (upper center) and two small, mature CLL cells (lower). 9 Blood Cell Identification Ungraded BCP-18 Referees Participants Performance Identification No.

8 % No. % Evaluation Platelet, normal 86 5275 Educational The Blood component identified by the arrow is a platelet, as correctly identified by of referees and of participants. Platelets are small, blue-gray fragments ( to 3 m in diameter) of megakaryocytic cytoplasm. Fine, purple-red granules are aggregated at the center or dispersed throughout the cytoplasm. Some have long cytoplasmic projections or ruffled margins. They are typically single but may form aggregates. This image also contains small CLL cells and larger prolymphocytes with a prominent nucleolus. 10 Blood Cell Identification Ungraded BCP-19 Referees BCP Participants Performance Identification No. % No. % Evaluation nRBC, normal or abnormal morphology 86 5302 Educational The arrowed cell is a nucleated red Blood cell, as correctly identified by of referees and of participants. The term nucleated red Blood cell includes all erythroblasts/normoblasts circulating in the peripheral Blood , regardless of maturational stage.

9 Most often circulating nucleated red Blood cells are in the later stages of maturation (orthochromatophilic or sometimes polychromatophilic stage). The nucleated red cell in the image contains a small, round nucleus with pyknotic chromatin and slightly greyish cytoplasm. It is smaller than the small CLL lymphocytes and prolymphocytes (below the nucleated red cell) in this case. Nucleated red Blood cells can be seen in the peripheral Blood with bone marrow replacement processes ( metastatic tumor, marrow infiltration by leukemia/lymphoma, fibrosis, granulomas, etc), rapid red cell production ( hemolytic anemias), or with other abnormalities of erythroid maturation. 11 Blood Cell Identification Ungraded BCP-20 Referees Participants Performance Identification No. % No. % Evaluation Eosinophil, any stage 85 5286 Educational Basophil, any stage 1 3 Educational The arrowed cell is an eosinophil, as correctly identified by of referees and of participants.

10 Eosinophils are round to oval granulocytes found in peripheral Blood , bone marrow, and tissues of normal individuals. The abundant coarse red-orange granules of eosinophils allow them to be easily recognized. These granules are larger than the secondary granules seen in neutrophils, usually do not overlie the nucleus, and exhibit a refractile appearance by light microscopy. In mature eosinophils, as in this image, the nucleus exhibits segmentation with two or more lobes connected by a thin filament. An increased number of eosinophils may occur associated with drug reactions, parasitic infections, allergic conditions, various malignancies, collagen vascular disorders, pulmonary diseases, and skin disorders. This image also contains small CLL lymphocytes and prolymphocytes. Joan E. Etzell, MD, Vice Chair Hematology and Clinical Microscopy Resource Committee