ppt 9 Flashcards
Hematology Tests
• White cell count • White cell differential • Red cell count • RBC morphology • Hematocrit (HCT) • Hemoglobin (Hb) • Indices – MCV – MCH – MCHC • Sedimentation Rate • Methemoglobin • Iron and Total Iron Binding Capacity • Platelet count
Coagulation Tests
• Bleeding Time • Prothrombin Time • Plasma Thrombin Time • Plasma Fibrinogen • Fibrin Split Products • Partial Thromboplastin time • Activated (Whole Blood) Clotting Time
White Cell Count
• Total number of WBCs (estimated) – performed by machine – normal range: 4 -10.5 thousand/cubic millimeter • There are five types of WBCs: - neutrophils - lymphocytes - monocytes - eosinophils - basophils
Leukocytosis may also occur after:
- epilepsy
- pregnancy and child birth
- anesthesia
- splenectomy (removal of the spleen)
Left shift
- is an increase in the number of immature neutrophils (band cells) in the peripheral blood (their normal amount is 2-6% of all neutrophils)
- usually occurs in:
- inflammation
- infection
- cancer
Right shift
- in the ratio of immature to mature neutrophils is considered with reduced count or lack of “young neutrophils” (metamyelocytes, and band neutrophils) in blood smear, associated with the presence of “giant neutrophils”
- This fact shows the suppression of bone marrow activity
Leukopenia (leukocytopenia or leucopenia)
- is a decrease in the number of white blood cells (leukocytes)
found in the blood
• Leukopenia develops due to:- immunodeficiency disorders
- chemotherapy
- radiation therapy
- some medications (e.g. immunosuppressive drugs)
Normal values Neutrophils
= 50 - 65%
2–5 lobes of nucleus
Normal values Lymphocytes
= 20 - 35%
Normal values Monocytes
= 2 - 8%
Normal values Eosinophils
= 1 - 6%
2 lobes of nucleus
Normal values Basophils
= 0.5 -1%
2 - 3 lobes of nucleus
polymorphonuclear
- more than one lobe of nucleus
- also known as granulocytes
- neutrophils (2–5 lobes of nucleus)
- eosinophils (2 lobes of nucleus)
- basophils (2 - 3 lobes of nucleus)
mononuclear
- single nucleus
- also known as agranulocytes
- lymphocytes
- monocytes
Function of neutrophils:
- first WBC to enter to the site of acute inflammation
- phagocytosis
• Their increase is associated with: - bacterial infection
- fungal infection
- inflammation
• Lifetime of neutrophils: 6 hours – few days
Segmented neutrophils
segs
mature neutrophils Nucleus should have 2-5 lobes
Banded neutrophils (band)
- immature neutrophils
- Nucleus are of horseshoe shape
Neutrophilia (over 70%)
• Infection (bacterial, fungal) • Trauma • Inflammatory diseases • Stress
Neutropenia (less 45%)
• Bone Marrow depression – Aplastic anemia – Megaloblastic anemia • Viral infection • Autoimmune disorders
• Functions of eosinophils:
- histaminase locating in cytoplasmic granules inactivates histamine - phagocytosis - production of eicosanoids (modulating inflammatory responses) - physiological role in organ formation (e. g. postgestational mammary gland development) • They play roles in: - allergic reactions - bronchial asthma - parasitic (worm) infestations - Lifetime of eosinophils: 8-12 days
Increased level(over 6%) eosinophilia
• Allergic reaction • Atopic bronchial asthma • Parasitic infection (worms): – flukes, roundworm, nematode, trichenella • Skin diseases • Leukemia (CML) • Hodgkin's disease
Decreased level (less 1%) eosinopenia
- Stress
- Cushing’s disease
- Aplastic anemia
- Brucellosis
Function: basophils synthesize and store:
= histamine
= anticoagulant heparin (prevents blood from clotting too
quickly)
• They play role in:
- inflammation (due to presence of histamine)
- type I hypersensitivity, or anaphylactic reactions
- ectoparasite infections (e.g. ticks etc.)
- cancer
• Lifetime of basophils: few hours to few days
Increased level (over 2%) basophilia
• Chronic myelocytic leukemia (CML) • Hodgkin’s disease • Ulcerative colitis • Anaphylactic reactions (allergy) • Polycythemia • Infection (e.g. TB, chickenpox)
Decreased level (less than 0.5%) basopenia
- Hyperthryroidism
- Ovulation
- Pregnancy
- Stress
- Aplastic anemia
Functions of lymphocytes:
- are effector cells of the immune system
- B-cells produce plasma cells (for further antibody production)
- participation in regulation of the immune system
- antiviral, antitumor, anti-graft activity
• Lifetime of lymphocytes: years for memory cells, weeks for all others
Increased level (over 45%) lymphocytosis
• Viral infection • Autoimmune disorders • Infectious mononucleosis (atypical lymphocytes) • Lymphatic (lymphocytic) leukemia
Decreased level (less than 20%) lymphopenia
- Chronic debilitating diseases
* High corticosteroid levels
Functions of monocytes:
- phagocytosis (most active of all phagocytic cells)
- mature into macrophages:
1) Langerhans cells - in epidermis
2) Alveolar macrophages – in lungs
3) Microglia – in CNS
4) Kupffer cells – in liver - inflammation
• Monocytes are associated with: - tissue damage and trauma,
- chronic infectious diseases
- autoimmune diseases,
Increased level (over 8%) monocytosis
- tuberculosis, hepatitis, malaria, typhoid, leishmaniasis - diffuse connective tissue diseases - subacute bacterial endocarditis - myeloma - monocytic leukemia
Decreased level (less than 2%) monocytopenia
- acute infections
- stress
- treatment with glucocorticoids
- aplastic anemia
- acute myeloid leukemia
Red Blood Cell Count
- Main component of blood
- Helps estimate carrying capacity for oxygen
- Normal range: 4.2 - 6.1 million/cubic millimeter
- Increased count of RBC - polycythemia
- Decreased count of RBC - anemia
- Production is promoted by erythropoetin
- Erythropoetin level is controlled by oxygen level in tissues
RBC lifetime
approximately 4 months
anisocytosis
- Different size
- means the unequal size of RBC
- macrocytes
- microcytes
poikilocytosis
- Different shape
- abnormal shape of RBC, it represents the
abnormalities of membrane or Hb of RBC causing remodeling - types:
-elliptocytes (oval)
-tear drop
-sickle cell
-schistocytes
-crenated
-burr cells
-spur cells
-target cells
-spherocytes
macrocytes– increased diameter of RBC, found in:
- megaloblastic anemia -autoimmune hemolytic -anemias
- alcoholism
- chronic liver diseases
microcytes – decreased diameter of RBC, found in:
- iron-deficiency anemia -thalassemia
- sickle cell anemia
- spherocytosis
elliptocytes (oval) – found in:
- hereditary elliptocytosis (hemolytic anemia)
- thalassemia
- iron-deficiency
anemia - myelofibrosis (when bone marrow is replaced by non-hemopoetic tissue, scar tissue)
tear-drop – found in:
myelofibrosis
sickle cells (drepanocytes) – rod-shaped, boat- shape, oat-shaped, found in:
sickle cell anemia
schistocytes (red cell fragments) – fragments are small, spherical, triangular or irregular, found in:
- hemolytic anemias
burns - iron-deficiency anemia
- thrombotic thrombocytopenia purpura
crenated
– multiple short symmetric
projection (10-30 spicules of equal length);
not related to any disease
burr cells (a.k.a. echinocytes) –irregular asymmetric projections, small cells, found in:
- uremia
- hemolytic anemia
- pyruvate kinase deficiency
- hypomagnesemia,
- hypophosphatemia long-distance runners
spur cells (a.k.a.acanthocytes) – with long irregular unequal spicules, found in:
- liver diseases (e.g. liver cirrhosis)
- uremia
- thrombotic thrombocytopenic purpura
target cells (a.k.a. codocytes) – that have the appearance of a shooting target, have increased surface
area (due to increased cholesterol and lecithin), found
in:
- obstructive liver diseases
- abnormal hemoglobin diseases (SCD, thalassemia)
- iron-deficiency anemia
spherocytes – loss of biconcavity, smaller in
diameter, dark color without central pallor area, found in:
- hereditary spherocytosis
- burns
- after drug toxicity
hypochromia – when RBCs are paler than normal due to low hemoglobin concentration, found in:
- iron deficiency
- thalassemia
- sideroblastic anemia
hyperchromic - dark red cells due to an increase in the ratio of the weight of hemoglobin to the volume of the RBC, found in:
- hereditary spherocytosis
- megaloblastic anemias
basophilic stippling (punctate basophilia) –
aggregates of ribosomes looking like dark blue granules
throughout the cells, found in:
- lead poisoning
- thalassemia
- sideroblastic anemia
cabot rings are dark ring-shaped, figure eight structure
(microtubules or remnants of the nuclear membrane),
found in:
- lead poisoning
- pernicious anemia,
- thalassemia
Howell-Jolly bodies – DNA nuclear remnants,
single deep purple color, found in:
- megaloblastic anemias
- hemolytic anemia
- post-splenectomy
Heinz body - denatured hemoglobin
glucose-6-phosphate dehydrogenase deficiency
reticulocytes
– immature red cells with cytoplasmic RNA,
appear as diffusely pale blue color cells
- The number of reticulocytes is a good indicator of bone
marrow activity
Rouleaux
- are stacks or aggregations of RBCs
- ## occur when the plasma protein concentration (particularly of fibrinogen and globulins) is high
Conditions which cause increased rouleaux formation include:
- infections
- inflammatory diseases
- connective tissue disorders
- malignant tumors (e.g. multiple myeloma)
- diabetes mellitus (diabetic retinopathy)
Hematocrit (HCT)
- is a blood test that measures the percentage of the volume of whole blood that is made up of
red blood cells. This measurement depends on the number of
red blood cells and the size of red blood cells
normal hematocrit
- 45% for men
- 40% for women
A high HCT indicates
polycythemia
• polycythemia vera • dehydration • COPD (hypoxia) • congenital heart disease • kidney tumor that produces excess erythropoietin
A low HCT indicates anemia
• bleeding • overhydration • nutritional deficiencies such as iron, folate, vitamin B12 • bone marrow disorders • kidney failure (decreased production of erythropoietin) • excessive destruction of RBC
A hematocrit of less than 15% can result in
cardiac failure
A hematocrit of over 60% may result in
spontaneous blood clotting
Hemoglobin (Hb or HGB)
- Each gram of hemoglobin binds 1.34 ml of O2
* Normal levels 11.6-15.2 g/dl
Increased hemoglobin levels indicate:
- polycythemia vera
- dehydration
- cor pulmonale
- pulmonary fibrosis
Decreased levels typically found in:
- iron deficiency anemia
- hemolytic anemia, hemoglobinopathies (sickle cell disease, thalassemia)
- renal failure
Rule of Three
- RBC count, HGB, and HTC
- The hemoglobin should be three times RBC count.
-Example: RBC is 5 million/cubic mm. Based on rule of three: 5 x 3 = 15 (this is HGB in g/dl) - The hematocrit should be three times the hemoglobin.
-Example: HGB is 15 g/dl. Based on rule of three:
15 x 3 = 45 (this is HTC in %) - The hematocrit should be nine times the RBC.
-Example:
RBC is 5 million/cubic mm. Based on rule of three: 5 x 9 = 45 (this is HTC in %)
-This rule of three can be only applied to samples with normal size and shape of erythrocytes
Mean Corpuscular Volume (MCV)
-average size of red blood cell
- calculated by dividing the hematocrit by the total number of red blood cells, then multiplied by 10
MCV= (Hct x 10)/RBC
- Normal range is 80-99 femtoliters (fL) – in normocytes
– MCV < 80 fL means smaller cell size (microcytes)
– MCV ≥ 100 fL means bigger cell size (macrocytes)
The Mean Corpuscular Hemoglobin (MCH), or “Mean
Cell Hemoglobin”
- the average mass
of hemoglobin per red blood cell - MCH = (Hb x 10)/RBC
-Normal range (normochromic) 27-31 picograms (pg)
MCH less than lower limit of normal
- hypochromic anemias:
- e.g. iron deficiency anemia, thalassemia
MCH within normal range - normal RBC,
- normochromic anemias:
- e.g. acute blood loss, aplastic anemia, polycythemia vera
MCH greater than upper limit of normal
– hyperchromic
anemias:
- e.g. megaloblastic anemia
Mean Corpuscular Hemoglobin Concentration (MCHC)
- is a measure of the concentration of hemoglobin in a given volume of packed RBCs
- MCH/MCV or (Hb x 100)/hct
- Normal ranges for blood tests are 32 to 36 g/dl
MCHC is diminished
the erythrocytes are hypochromic in microcytic anemias
e.g. iron deficiency anemia, chronic blood loss, thalassemia
MCHC is normal
the erythrocytes are normochromic in macrocytic
anemias due to larger cell size, though the hemoglobin
amount (MCH) is high, the concentration remains normal
MCHC is elevated
should ONLY occur when spherocytes are present
e.g. hereditary spherocytosis
Methemoglobin
- is a form of oxygen-carrying metalloprotein
that contains ferric (Fe3+)iron not the ferrous (Fe²+) of normal hemoglobin and has a decreased ability to bind O2
-results from the oxidation of the reduced state
(ferrous Fe²+) of heme to the trivalent (ferric Fe3+) form
-This form of hemoglobin cannot combine with oxygen,
therefore the oxygen transport function is lost, tissue hypoxia
can occur
-This form of hemoglobin cannot combine with oxygen,
therefore the oxygen transport function is lost, tissue hypoxia
can occur
Acquired methemoglobinemia results from:
- carbon monoxide (CO) poisoning
- medication (Tylenol), certain antibiotics
- anesthetics
Manifestations of methemoglobinemia:
<10% of MetHb - no clinical manifestations
10-20% - skin discoloration (bluish)
20-30% - headache, dyspnea, anxiety
30-50% - fatigue, dizziness, tachycardia, confusion
50-70% - coma, arrhythmia
>70% - death
There are two forms of inherited methemoglobinemia:
-The first form is problem with cytochrome b5 reductase
enzyme
-he second form of inherited methemoglobinemia is
caused by defects in the hemoglobin protein itself
the first form is problem with cytochrome b5 reductase enzyme
- type 1 (also called erythrocyte reductase deficiency) occurs when red blood cells lack this enzyme
- type 2 (also called generalized reductase deficiency) occurs when this enzyme doesn’t work anywhere in the body
The second form of inherited methemoglobinemia is
caused by
- defects in the hemoglobin protein itself
- This form is called hemoglobin M disease
- Only one parent needs to pass on the abnormal gene for the child to inherit the disease
The Erythrocyte Sedimentation Rate (ESR)
- is the rate at which red blood cells sediment in a period of one hour
- Very SENSITIVE but not SPECIFIC
Normal range: - males 1-13 mm/hour
- females 1-20 mm/hour
Increased ESR:
- inflammatory process
- infection
- neoplasm
- tissue destruction etc.
Decreased ESR:
- polycythemia vera
- sickle cell disease
- hyperviscosity syndrome
Serum iron
- is a test that measures how much iron is in blood
• Iron levels are highest in the morning
• Normal range of the iron in the blood: 60-170 mcg/dL
• 95% of all iron is complexed with transferrin
Higher-than-normal level
• hemochromatosis • hemolytic anemia • liver tissue issue • hemolysis (duo to blood transfusions)
Lower-than-normal levels
- iron deficiency anemia
- pregnancy
- intestinal conditions that cause poor absorption of iron
Total Iron Binding Capacity (TIBC)
- is a blood test that
measures maximum amount of iron that can be bound to
transferrin
- Normal range in the blood:
- TIBC: 240-450 mcg/dL
- transferrin saturation: 20-50%Higher-than-normal TIBC
• when the body’s iron stores
are low:
- iron deficiency anemia - late pregnancy
Lower-than-normal
TIBC
when the body's iron stores are high, or function of the liver is low:
- cirrhosis
- hemochromatosis
- hemolytic anemia
(e.g. thalassemia,
sickle cells disease)
- megaloblastic anemiaFerritin is
-the iron storage protein found in hepatocytes and reticulo-endothelial cells
-Normal value: 20-300 nanograms/ml
- Serum ferritin levels are generally accepted as reliable single
indicators of the presence of iron deficiency
High levels of ferritin (Iron Overload)
- hemochromatosis
- liver disease
- iron overload
- leukemia
- infection
- inflammation
Low levels of ferritin ( Depletion of Iron )
- iron deficiency
- pregnancy
Normal range of platelets
150- 400 thousand/microliter (mcl).
[In microscope 7-10 phf]
Count < 50 thousand/mcl platelets results in
spontaneous
bleeding
< 5 thousand/mcl platelets
fatal
Platelets arise from ____________ in bone marrow
megakaryocytes
Elevated platelet levels
- hemorrhage
- infection
- cancer
- iron deficiency anemia
- splenectomy
- pregnancy
Decreased platelet levels
• aplastic/hypoplastic marrow • infiltrative bone disease – neoplasms – infection • deficiency of: – folic acid – vitamin B12 • destruction in: – drug reactions – Autoimmune thrombocytopenias
Coagulation Tests
• Bleeding Time • Partial Thromboplastin time • Prothrombin Time • Activated (Whole Blood) Clotting Time • Plasma Thrombin Time • Plasma Fibrinogen • Fibrin Split Products
Bleeding Time
- Duration of bleeding after standardized incision
- Normal 3-6 minutes
- Not be done if platelet count is < 75 thousand/mcl
Elevated Bleeding Time (2 x Normal)
- Disorders associated thrombocytopenias
- Hodgkin’s disease
- Leukemia
- Disseminated Intravascular Coagulation (DIC)
- Severe liver disease
- Deficiency of clotting factors
- Uremia
- Drugs (especially NSAIDs)
- Vitamin K deficiency
Partial Thromboplastin Time (PTT)
-measures the efficacy of both the intrinsic and
common coagulation pathways
-used to investigate unexplained
bleeding or clotting
-used in conjunction with the prothrombin time which
measures the extrinsic coagulation pathway
-Normal range: 30-50 seconds
PTT is used for diagnosis of:
- hemophilia A, B
- liver diseases
- factors I, II, V, VIII, IX, X, XI, & XII deficiency
- disseminated intravascular coagulation
- vitamin K deficiency
Prothrombin Time (PT)
- is a blood test that measures extrinsic and common coagulation pathways
• Normal values (without blood thinning medicines):
11 – 13.5 seconds
• 2.5 increase of PT indicates bleeding disorder
• PT is not used for diagnostics of hemophilia
A prothrombin time test can be used to check:
- bleeding problems
- whether medicine to prevent blood clots is working
- presence of clotting factors I, II, V, VII and X
- liver damage (all clotting factors are produced in liver)
- vitamin K status
Plasma Thrombin Time (TT)
• The test only detects the activity of fibrinogen and gives
quick estimate of fibrinogen level
• Normal is 10-15 seconds
Plasma Thrombin Time Prolonged in:
- fibrinogen abnormalities (congenital or acquired):
hypofibrinogenemia, afibrinogenemia, dysfibrinogenemia - deficiency of fibrin formation (disseminated intravascular coagulation, abnormal circulating proteins due to
amyloidosis or multiple myeloma) - liver diseases
- heparin therapy
Plasma Fibrinogen (Factor I)
• This testing is used to evaluate the fibrinogen level
• Fibrinogen, also known as clotting factor I, is a plasma protein
that can be transformed by thrombin into a fibrin gel (“the clot”)
and is essential for blood clot formation
• Fibrinogen is synthesized in the liver and circulates in the
plasma
• Therefore, fibrinogen deficiency is a serious health problem
• Normal value 200-400 mg/dl
Decreased levels of Plasma Fibrinogen (Factor I)
– hereditary absence, deficiency, or defect of fibrinogen – abnormal fibrinolysis – end-stage liver diseases – bone marrow lesions – cancer of prostate, pancreas, lungs – disseminated intravascular coagulation
Increased levels of Plasma Fibrinogen (Factor I)
– cancer of stomach, breast, kidney
– tissue damage/trauma
– inflammation
- pneumonia or glomerulonephritis
Plasmin
- is an important enzyme present in blood that
degrades many blood plasma proteins, including fibrin clots
(fibrinolysis) - Normal level 10 mg/L
• Deficiency in plasmin may lead to arterial thrombosis, especially in young persons (as clots are not degraded adequately)
Elevated level in anticoagulant activity and disorders
with excessive bleeding (Plasmin?)
- disseminated intravascular coagulation
- myocardial infarction
- burns or sunstroke
- pulmonary embolism due to deep vein thrombosis
