O Troubleshooting

How Do I Obtain a Valid White Count When My Patient's White Count Is Outside of the Linearity Range?

Consider the case study presented earlier in this chapter. The white count is 199 X 109/L, which is out of the linearity range. Special techniques must be used by the technologist to obtain a valid white count on this sample. The technologist will notice that the white count is seen as a vote out + + + + on the automated screen, and this is the first alert that the count may be too high (out of the linearity range) to be recorded by the instrument. The first step is to dilute a small amount of the patient's sample, usually 1:2 dilution, and re-run it to see if a number can be obtained. If this dilution is still out of range then several more dilutions are tried until a reading can be obtained. Once a reading is obtained, then the technologist must remember to multiply by the dilution factor to obtain an accurate white count. The white count will be a critical value and must be called and reported to a responsible party. Additionally, each of the other parameters of the CBC must be examined to evaluate whether they are credible. The troubleshooting case in Chapter 11 outlines each of the steps necessary to resolve the total CBC on a troublesome patient such as this, examining each CBC parameter and the resolution steps. Although each of these procedures seems exhaustive, they are necessary to give the physician an accurate account of this patient's CBC.

WORD KEY Gout • Arthritic disorder marked by crystal formation

^ r i n (usually uric acid) in the joints or tissues

Clonal • Disease arising from a single cell

Deep vein thrombosis • Formation of a blood clot in the Hyperplasia • Increase in the number of cells in the bone deep veins of the legs, arms, pelvis, etc. marrow

202 Part III • White Cell Disorders

Myelofibrosis • Increase in the reticulin or fibrotic tissue in the bone marrow.

Myeloproliferative • Disease that results in the uncontrolled overproduction of normal-appearing cells in the absence of an appropriate stimulus

Organomegaly • Enlargement of the organs

Osteosclerosis • Abnormal increase in the thickening or density of bone

Plethora • Excess blood volume Pruritus • Itching

Therapeutic phlebotomy • Withdrawing blood for a medical purpose

Transient ischemic attack • Neurological defect, having a vascular cause, producing stroke symptoms that resolve in 24 hours

Trisomy • In genetics, having three homologous chromosomes instead of two


1. Jaffee ES, Harris NL, Stein H, Vardiman JW, eds. World Health Organization Classification of Tumors: Pathology and Genetics of Tumors of Haematopoietic Lymphoid Tissues. Lyon: IARC Press, 2001.

2. Vardiman JW, Harris NL, Brunning RD. The World Health Organization (WHO) classification of the myeloid neoplasms. Blood 100:2292-2302, 2002.

3. Murphy S, Peterson P, Iland H, Laszio J. Experience of the Polycythemia Vera Study Group with essential thrombocythemia: A final report on diagnostic criteria, survival and leukemic transition by treatment. Semin Hematol 34:29, 1997.

4. Berlin NI. Diagnosis and classification of the poly-cythemias. Semin Hematol 12:339-351, 1975.

5. Melo JV, Hughes TP, Apperley JF. Chronic myeloid leukemia. Hematology 1:132-152, 2003.

6. Drucker BJ, Sawyers CL, Kantarjian H, et al. Activity of a specific inhibitor of the BCR-ABL tyrosine kinase in the blast crisis of chronic myeloid leukemia and acute lymphoblastic leukemia with Philadelphia chromosome. N Engl J Med 344:1038-1042, 2001.

7. Goldman JM, Melo JV. Chronic myeloid leukemia-advances in biology and new approach in treatment. N Engl J Med 349:1451-1464, 2003.

8. Deininger MW, Goldman JM, Melo JV. The molecular biology of chronic myeloid leukemia. Blood 96: 3342-3356, 2000.

9. Calabretta B, Perrotti D. The biology of CML blast crisis. Blood 103:4020-4022, 2004.

10. Faderl S, Talpaz M, Estrov Z, Kantarjian HM. Chronic myelogenous leukemia: Biology and therapy. Ann Intern Med 131:207-219, 1999.

11. O'Brien SG, Guilhot F, Larson RA, et al. Imatinib compared with interferon and low-dose cytarabine for newly diagnosed chronic-phase chronic myeloid leukemia. N Engl J Med 348:994-1004, 2003.

12. Obrien SG, Tefferi A, Valent P Chronic myelogenous leukemia and myeloproliferative disease. Hematology 1:146-162, 2004.

13. Sawyers CL, Hochhaus A, Feldman E, et al. Imatinib induces hematologic and cytogenetic responses in patients with chronic myelogenous leukemia in myeloid blast crisis: Results of a phase II study. Blood 99:3530-3539,2002.

14. Reiffers J, Trouette R, Marit G, et al. Autologous blood stem cell transplantation for chronic granulocytic leukemia in transformation: A report of 47 cases. Br J Haematol 77:339-345, 1991.

15. Sawyers CL. Chronic myeloid leukemia. N Engl J Med 340:1330-1340,1999.

16. Onida f, Ball G, Kantarjian HM, et al. Characteristics and outcome of patients with Philadelphia chromosome negative, BCR/ABL negative chronic myelogenous leukemia. Cancer 95:1673-1684, 2002.

17. Bohm J, Schaefer HE. Chronic neutrophilic leukemia: 14 new cases of an uncommon myeloproliferative disease. J Clin Pathol 55:862-864, 2002.

18. Campbell PJ, Green AR. Management of Polycythemia Vera and Essential Thrombo cythemia. Am Soc Hematol Educ Program 2005; 201-205.

19. Bilrami S, Greenburg BR. Polycythemia rubra vera. Semin Oncol 22:307-326, 1995.

20. Spivak JL. Polycythemia vera: myths, mechanisms, and management. Blood 100:4272-4290, 2002.

21. Streiff MB, Smith B, Spivak JL. The diagnosis and management of polycythemia vera since the Polycythemia Vera Study Group: A survey of American Society of Hematology practice patterns. Blood 99:114-119, 2002.

22. Pearson TC, Messinezy M, Westwoos N, Green AR, et al. A polycythemia vera update: Diagnosis, pathobiology and treatment. Hematology 1:51-68, 2000.

23. Cazzola M, Guarnone R, Cerani P et al. Red blood cell precursor mass as an independent determinant of serum erythropoietin level. Blood 91:2139-2145, 1998.

24. Swolin B, Weinfeld A, Westin J. A prospective long term cytogenetic study in polycythemia vera in relation to treatment and clinical course. Blood 72:386-395, 1998.

25. Lengfelder E, Berger U, Hehlman R. Interferon alpha in the treatment of polycythemia. Hematology 79:103-109, 2000.

26. Berk PD, Goldberg JD, Donovan PB, et al. Therapeutic recommendations in polycythemia based on Poly-cythemia Vera Study Group protocols. Trans Assoc Am Physicians 99:132-143, 1986.

27. Georgii A, Buesche G, Kreft A. The histopathology of chronic myeloproliferative diseases. Baillieres Clin Haematol 11:721-749, 1998.

28. Barosi G. Myelofibrosis with myeloid metaplasia: Diagnostic definition and prognostic classification for clinical studies and treatment guidelines. J Oncol 17: 2954-2970, 1999.

29. Tefferi A. Myelofibrosis with myeloid metaplasia. N Engl J Med 341:1255-1265, 2000.

30. Tefferi A, Mesa RA, Schroeder G, Hanson CA, Li CY, Dewald GW Cytogenetics findings and their clinical relevance in myelofibrosis with myeloid metaplasia. Br J Haematol 113:763-761, 2001.

31. Manoharan A. Idiopathic myelofibrosis: A clinical review. Int J Hematol 68:355-362, 1998.

32. Mesa RA, Hanson CS, Rajkumar V, Schroeder G, Tefferi A. Evaluation and clinical correlations of bone marrow angiogenesis in myelofibrosis with metaplasia. Blood 96:3374-3380,2000.

33. Reilly JT. Idiopathic myelofibrosis: Pathogenesis, natural history and management. Blood Rev 11:233-242, 1997.

34. Dickstein JI, Vardiman JW Hematopathologic findings in the myeloproliferative disorders. Semin Oncol 22:355-373, 1995.

35. Spivak JL, Barosi G, Tognoni G, et al. Chronic myelo-proliferative disorders. Hematology 1:200-224, 2003.

36. Dupriez B, Morel P, Demory JL, et al. Prognostic factors in agnogenic myeloid metaplasia: A report on 195 cases with a new scoring system. Blood 88:1013-1018, 1996.

37. Tefferi A, Mesa RA, Nagomey DM, Schroeder G, et al. Splenectomy in myelofibrosis with myeloid metaplasia: A single-institution experience with 223 patients. Blood 95:226-233, 2000.

38. Deeg HJ, Gooley TA, Flowers ME, et al. Allogenetic hematopoietic stem cell transplantation for myelofibro-sis. Blood 102:3912-3918, 2003.

39. Cervantes F, Barosi G, Demoray JL, et al. Myelofibrosis with myeloid metaplasia in young individuals: Disease characteristics, prognostic factors and identification of risk groups. Br J Haematol 102:684-690, 1998.

40. Tefferi A, Solberg LA, Silverstein MN. A clinical update in polycythemia vera and essential thrombocythemia. Am J Med 109:141-149, 2000.

41. Nimer S. Essential thrombocythemia: Another "heterogeneous disease" better understood? Blood 93:415-416, 1999.

42. Harrison CN, Gale RE, Machin SJ, Linch DC. A large proportion of patients with a diagnosis of essential thrombocythemia do not have a clonal disorder and may be at lower risk of thrombotic complications. Blood 93:417-424, 1999.

43. Cortelazzo S. Finazzi G. Ruggeri M, Hydroxyurea for patients with essential thrombocythemia and a high risk of thrombosis. N Engl J Med 332:1132-1136, 1995.

44. Ruggeri M, Finazzi G, Tosetro A, et al. No treatment for low-risk thrombocythemia: Results from a prospective study. Br J Haematol 103:772-777, 1998.

45. Fenaux P, Simon M, Caulier MT. Clinical course of essential thrombocythemia in 147 cases. Cancer 66:549-556, 1990.

46. Hehlmann R, Jahn M, Baumann B. Essential thrombocythemia: Clinical characteristics: A study of 61 cases. Cancer 61:2487-2496, 1988.

47. Sterkers Y, Preudhomme C, Lai JL, et al. Acute myeloid leukemia and myelodysplastic syndromes following essential thrombocythemia treated with hydroxyurea. Blood 91:616, 1998.

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