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Department of Pathology and Laboratory Medicine

Department of Pathology and Laboratory Medicine

Hematology and Coagulation

Christie Falk (Supervisor)
Jennifer Jeffries (PM Supervisor)

Routing Hematology Testing

  1. Complete Blood Count-No differential: Includes WBC, RBC, Hgb, HCT, MCV, MCH, MCHC, Plts and RDW.
  2. Complete Blood Count with Automated Differential: Includes all of the above plus a five-part differential. Cells identified are Granulocytes (includes Polys and Bands), Lymphocytes, Monocytes, Eosinophils, and Basophils.
  3. Manual Differential: Includes WBC differentiation, RBC morphology, and platelet estimation. This is not an orderable test. If the automated differential fails pre-set flagging criteria, a manual differential is then performed by the laboratory. It is charged at that time.
  4. Platelet Count: This test is a part of the blood count but may be ordered separately. On occasion, abnormalities of the sample may make it necessary to perform a manual, phase platelet count.
  5. Reticulocyte Count: Performed by flow cytometry method on the Coulter. If required STAT during off-hours, or when interferences exist in the sample, a manual count will be performed.
  6. Sedimentation Rate: Minimum volume for analysis is 3 mL EDTA blood.
  7. Microhematocrit: Minimum requirement for analysis is 2 heparinized microcapillary tubes for microcentrifugation.
  8. Body Fluid Analysis: Includes a manual red and white cell count and a differential based on a cytocentrifuge prepared smear. CSF specimens are performed STAT. Synovial fluid analysis may also includes Crystals.

    NOTE: When specific cellular or marked abnormalities are noted on any of the above tests, review by a Pathologist is initiated and, when appropriate, an interpretive report is sent to the chart.

Special Hematology Testing

  1. Eosinophil Count: Performed by automated cell counter unless interferences are present. Then performed by manual methods.
  2. Malaria Smears: Both thick and thin smears reviewed. Sent to Public Health for speciation.
  3. Sugar Water Test: Screen for PNH
  4. Heinz Body Stain
  5. Betke-Kleihauer
  6. Leukocyte Alkaline Phosphatase Stain: Specimen consists of 6-8 peripheral blood smears from fingerstick. Test is not performed on weekends, evenings or holidays.
  7. Hemoglobin Analysis (Electrophoresis): May include Electrophoresis by Isoelectric Focusing; Hemoglobin A2, Hemoglobin, Fetal, Quantitative, Fetal, Betke Kleihauer; Interpretation and blood count. Performed weekly, dayshift only.

Acceptable Specimens for Routine Hematology Testing


  1. 1. EDTA Anticoagulated:
    1. 5.0 cc tube, minimum ? full
    2. 3.0 cc tube, minimum ? full
    3. 1 lavender top microvette filled to second line (500 mL) for newborns.
      Note: Sedimentation Rate: minimum requirement is a full 3 mL EDTA tube.
  2. CSF specimens may be sent in sterile CSF tube.
  3. Synovial fluids should be sent in 1 heparinized tube and 1 red top tube.
  4. All samples must be received in the Hematology Laboratory no later than 4 hours after collection.
  5. Specimens containing clots will be rejected for cell counts. Only a differential will be performed when a fluid is received containing clots.

      Specimen and smear retention:
    1. EDTA blood tubes are retained 24 hours after testing.
    2. Stained peripheral blood and fluid smears are retained for 4 weeks after testing.

Routine Coagulation Testing

  1. (PT) Prothrombin Time resulted as INR
  2. (aPTT) Activated Partial Thromboplastin Time
  3. Fibrinogen (Semiquantitative)
  4. Fibrin Monomer
  5. FDP-Fibrin(ogen) Degradation Products
  6. D-Dimer
  7. Thrombin Time
  8. Antithrombin
  9. Plasminogen
  10. Inhibitor Screen
  11. Cryofibrinogen/Cryoglobulin
  12. Heparin

Special Coagulation Testing

Unless otherwise noted. Available dayshift Monday-Friday only.

  1. Factor Assays: Performed daily, Monday through Friday, dayshift only. Available as STAT at other times with Pathologist's approval.
  2. Inhibitor Assay: Specify factor
  3. Ristocetin Co-Factor: Performed on Wednesdays.
  4. Von Willebrand's Antigen: Performed on Wednesdays.
  5. Factor XIII Screen
  6. Protein C Assay: Performed on Tuesdays.
  7. Protein S Assay: Performed on Tuesdays.
  8. Dilute Russel's Viper Venom Test (DRVVT): Performed Tuesdays.
  9. Anti-Cardiolipin Antibody Test: Performed on Thursdays.
  10. Anti-Phospholipid Antibody Test: Performed on Thursdays.
  11. Heparin Associated Antibody Test
  12. PFA
  13. Platelet Aggregation

Acceptable Specimens for Hemostasis Testing

One 5 mL blue-top tube with liquid (3.2% buffered acid citrate) is adequate for all of the above mentioned tests except:

  • Cryofibrinogen - 2.5 cc lavender (EDTA) top tube or red top maintained at 37?C And sent to the lab ASAP following collection.
  • Cryoglobulin - 7 cc red top maintained at 37?C.
  • Fibrin(ogen) Degradation Products - blue top tube with powder.
  • Call SARC at extension 4-0500 if any of the above tubes are needed.

Technique for Collection of Hemostasis Samples

Use a "two-syringe" technique whenever drawing any specimen for hemostasis testing, i.e., the first 3 mL from a venipuncture should be drawn into a separate tube or syringe and set aside; then, blood from the second tube or syringe can be used for the hemostasis sample. The sample should be put on ice immediately. Drawing a hemostasis sample from a heparin lock is not advised due to the risk of heparin contamination. The ratio of blood:anticoagulant is very critical. Patients with hematocrits less than 20% or greater than 60% require a special tube available from the laboratory. Please call 4-0500 to request these tubes. All tubes drawn for coagulation work must be full.

Incompletely filled tubes and specimens received more than four (4) hours after collection will be rejected.