Transcript Complete blood count Lab Tests

Complete blood count &
Coagulation Screening
Lab1 Tests
DR. HAILIN WU
DR. YOSEPH FELEKE
Blood plasma
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Blood plasma is prepared by spinning a tube of fresh
blood containing an anticoagulant in
a centrifuge until the blood cells fall to the bottom of
the tube.
The blood plasma is then poured or drawn off.
Blood Plasma
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Approximately 90% water
Contains:
Ions – Na+ and ClNutrients – sugars, amino acids, lipids, cholesterol, vitamins and
trace elements
Three main proteins - Albumin (60%), globulin (35%),
fibrinogen (4%)
Dissolved Gasses – including O2 and CO2
Waste Products – other protein wastes such as urea and
bilirubin
Complete Blood4 Count (CBC)
A series of tests of the peripheral blood that provides
valuable information about the hematologic
system.
Is very inexpensive and can be performed rapidly
Complete Blood Count (CBC)
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 Provides information on cellular components of
blood
Includes RBC count,
Hemoglobin (Hgb),
Hematocrit (Hct),
RBC indices,
White blood cell (WBC) count and differential,
Platelet count
RBC Count
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 Test Range and Collection
 (RBC, or erythrocyte count), whole blood
 4.3–6.0 x 106/mcL (male)
 3.5–5.5 x 106/mcL (female)
Erythrocyte count (RBC)
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Increased in: erythrocytosis, congenital heart disease,
severe COPD, polycythemia vera, severe dehydration,
hemoglobinopathies
Decreased in: anemia, hemoglobinopathy, hemorrhage,
bone marrow failure, renal disease, leukemia, prosthetic
valves, normal pregnancy, multiple myeloma, Hodgkin
disease, lymphoma, dietary deficiency
Erythrocyte Sedimentation Rate(ESR)
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Female: 1-25 mm/hr
Male: 0-17 mm/hr
Increased:
inflammatory diseases, e.g. rheumatic conditions
Alternative calculation of normal value:
Female: (age + 10) / 2
Male: age / 2
Hemoglobin
 Test Range and Collection
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whole blood (Hb)
Male: 13.6–17.5
Female: 12.0–15.5 g/dL (age-dependent)
Increased in: Hemoconcentration (as in dehydration,
burns, vomiting), polycythemia, extreme physical
exercise.
Decreased in: Macrocytic anemia (liver disease,
hypothyroidism, vitamin B12 deficiency, folate
deficiency), normocytic anemia (early iron deficiency,
anemia of chronic disease, hemolytic anemia, acute
hemorrhage), and microcytic anemia (iron deficiency,
thalassemia).
Hypertriglyceridemia and very high white blood cell
counts can cause false elevations of Hb
Hematocrit
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Hematocrit
Men 40–54%; women 37–47%
Calculated from MCV and red cell number; the percentage volume of red
cells in a given volume of blood
Increased: Primary polycythemia (polycythemia vera), secondary
polycythemia (reduced fluid intake or excess fluid loss), congenital or
acquired heart and lung disease, high altitude, heavy smoking, tumors
(renal cell carcinoma, hepatoma)
Decreased: Megaloblastic anemia (folate or B12 deficiency); iron
deficiency anemia; sickle cell anemia or other hemoglobinopathy; acute
or chronic blood loss; sideroblastic anemia, hemolysis; anemia due to
chronic disease, dilution, alcohol, or drugs
RBC indices
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 Measures size and hgb content of RBCs
 Used to classify anemias
 Includes Mean corpuscular volume (MCV), mean
corpuscular hemoglobin (MCH), mean corpuscular
hemoglobin concentration (MCHC), red blood cell
distribution width (RDW)
MCV
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 Measure of average volume/size of single RBC
 MCV = Hct (%) x 10/RBC (million/mm3)
 Useful in anemia classification
 Normal: 80 – 100 mm3
 Increased in (macrocytic): pernicious anemia (vit B12
deficiency), folic acid deficiency, antimetabolic therapy,
alcoholism, chronic liver disease, hypothyroidism
 Normocytic: bone marrow failure/replacement, acute
blood loss, chronic diseases, hemolytic anemias
 Decreased in(microcytic): Fe deficiency anemia,
thalassemia, anemia of chronic illness
Mean Corpuscular Hemoglobin (MCH)
 Test Range and Collection
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blood (MCH)
26–34 pg
MCH = (Hb/RBC) x 10
Increased in: Macrocytosis, hemochromatosis.
Decreased in: Microcytosis (iron deficiency,
thalassemia), hypochromia (lead poisoning,
sideroblastic anemia, anemia of chronic disease).
Low MCH can mean hypochromia or microcytosis or
both.
High MCH is evidence of macrocytosis.
MCHC
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 Measure of average [hgb] within a single RBC
 MCHC = Hgb (g/dL) x 100/Hct (%)
 37 g/dL = maximum Hgb able to fit into an RBC (cannot
be hyperchromic)
 Normal (normochromic): 32 – 36 g/dL
 Increased in : spherocytosis, intravascular
hemolysis, cold agglutinins
 Decreased in (hypochromic): Fe deficiency
anemia, thalassemia
RDW
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 Measure of variation of RBC size (indicator of degree
of anisocytosis)

Useful in anemia classification
 Normal: variation of 11.5 – 16.9%
 Increased in :
Fe deficiency anemia, vit B12 or folate
deficiency anemia, hemoglobinopathies, hemolytic
anemias, posthemorrhagic anemias
Platelet Count
 Test Range and Collection
 whole blood (Plt)
 150–450 x 103/mcL
 [x 109/L]
 Panic: <25 x 103/mcL
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Increased in: Myeloproliferative disorders (chronic myeloid
leukemia, essential thrombo-cythemia, myelofibrosis), acute
blood loss, post-splenectomy, pre-eclampsia, reactive
thrombocytosis secondary to inflammatory disorders, infection,
tissue injury, iron deficiency, malignancies.
Decreased in: Decreased production: bone marrow suppression
or replacement/infiltration, chemotherapy, drugs, alcohol,
infection (eg, HIV), congenital marrow failure; increased
destruction or excessive pooling: hypersplenism, DIC, platelet
antibodies
Thrombocyte count
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The terms thrombocytopenia and thrombopenia
refer to a disorder in which there is a relative decrease of
thrombocytes, commonly known as platelets, present
in the blood.
A normal human platelet count ranges from 150,000 to
450,000 platelets per microlitre of blood.
These limits are determined by the 2.5th lower and upper percentile, so values
outside this range do not necessarily indicate disease. One common
definition of thrombocytopenia is a platelet count below 50,000 per
microlitre.
Total WBCs (leukocytes)
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Measurement of total WBC count
Consists of total # of WBCs/mm3 of peripheral venous blood
Part of “routine” testing
Useful for evaluation of infection, neoplasm, allergy &
immunosuppression
Normal: 4,000 – 10,000/mm3
Critical: < 2,500 or > 30,000/mm3
Increased in:(leukocytosis): infection, malignancy, trauma,
stress, hemorrhage, tissue necrosis, inflammation,
dehydration, thyroid storm
Decreased in: (leukopenia): drug toxicity, bone marrow
failure, overwhelming infections, dietary deficiency,
congenital marrow aplasia, bone marrow infiltration,
autoimmune disease, hypersplenism
White Blood Cell Count w/
Differential
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 Test Range and Collection
 blood
 Reference ranges are age- and laboratory-specific
 Adult ranges: WBC 4.5–11.0 x 103/mcL;
 differential:
segmented neutrophils 50–70%;
 band neutrophils 0–5%;
 lymphocytes 20–40%;
 monocytes 2–6%;
 eosinophils 1–4%;
 basophils 0–1%.


Panic: <1.5 x 103/mcL
White Blood Cell Count w/
Differential
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Increased in: Acute infections, inflammatory disorders,
acute and chronic leukemias, myeloproliferative
disorders, circulating lymphoma, tissue
injury/necrosis, various drugs, corticosteroids,
allergies, hypersensitivity reactions, stress, smoking.
Decreased in: Infections, constitutional and acquired
myeloid hypoplasia, myelosuppression (eg,
chemotherapy, radiation, various drugs),
myelodysplasia, collagen vascular diseases,
hypersplenism, cyclic neutropenia, autoimmune
neutropenia, alcoholism
It is important to perform a manual differential in certain
conditions such as presence of blasts, immature
granulocytes, nucleated red blood cells, leukemia or
lymphoma cells, plasma cells, or dysplasia.
Coagulation Screening
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 Used to evaluate a patient’s blood coagulation
system status
 Has multiple factors that are measured:
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


Prothrombin Time (PT)
Partial Thromboplastin Time (PTT)
INR
Bleeding time (BT)
Prothrombin Time (PT)
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 Test Range and Collection
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
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whole blood (PT)
11–15 seconds
(laboratory specific)
Increased in: Warfarin, liver disease, DIC, vitamin K
deficiency, hereditary deficiency in factors VII, X, V and II,
fibrinogen abnormality (eg, hypofibrinogenemia,
afibrinogenemia, dysfibrinogenemia), circulating
anticoagulant affecting the PT system (rarely lupus
anticoagulant), massive transfusion.
Routine preoperative measurement of PT is unnecessary
unless there is clinical history of a bleeding disorder
Partial Thromboplastin Time (PTT)
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 Test Range and Collection
 activated, plasma
 (aPTT)
 25–35 seconds (range varies)
 Panic: 60 seconds (off heparin)
 Increased in: Deficiency of any individual coagulation factor except
Factors XIII and VII, presence of nonspecific inhibitor (eg, lupus
anticoagulant), specific factor inhibitor, von Willebrand disease (PTT
may also be normal), hemophilia A and B, DIC. Drugs: heparin,
direct thrombin inhibitor (eg, hirudin, argatroban), warfarin.
 Decreased in: Hypercoagulable states (eg, increased factor VIII
levels).
 PTT cannot be used to monitor very high doses of heparin (eg,
cardiac bypass surgery) because the clotting time is beyond the
analytical measurement range of PTT.
INR
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 Test Range and Collection
 International Normalized Ratio (INR) is calculated.
 INR = [Patient PT/Normal mean PT]
 Warfarin therapeutic range is INR 2.0–3.0.
Bleeding has been reported to be three times
more common in patients with INRs of 3.0–4.5
than in patients with INRs of 2.0–3.0.
BT
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Normal 1-6 min
Measures quality of platelets
Prolonged in thrombocytopenia
Bleeding time is a medical test done on someone to
assess their platelets function.
It involves making a patient bleed then timing how
long it takes for them to stop bleeding.