Good Morning

SEMINAR

Presented by:

Dr.Prashant Munde ( MDS- I )

Guided by : Dr. Mrs. SHUBHANGI KHANDEKAR

( PROFESSOR & GUIDE )

Dr. Mrs. ALKA DIVE( PROFESSOR & H.O.D)

INVESTIGATIONS FOR HAEMORRHEGIC DISORDERS

Hemorrhagic Disorders

Hemorrhagic or Bleeding disorders are a group of

conditions in which there is a problem with the body's

blood clotting process.

These disorders can lead to heavy and prolonged bleeding

after an injury. Bleeding can also begin on its own.

Defects in blood coagulation usually give abnormal

coagulation tests and C.T.

CausesNormal blood clotting involves coagulation

factors which act together with other

chemicals to form fibrin that stops bleeding.

Problems can occur when certain coagulation

factors are low or missing.

Bleeding disorders can also result from having

poorly working or too few platelets.

Some bleeding disorders are present at birth

and are passed through families (inherited).

Others develop from:

Illnesses such as vitamin K deficiency or severe

liver disease.

Treatments such as the use of drugs to stop

blood clots (anticoagulants) or the long-term

use of antibiotics.

Diagnosis of Hemorrhagic Disorders

Present history: Rash following infection, abdominal and joint pain.

Family History: For evidence of inheritance of any bleeding tendencies.

Past History: Excessive, prolonged bleeding of the surgical interventions as tonsillectomy, circumcision or tooth extraction.

Physical Examination: General condition, type and distribution of the rash, fever, organ enlargement, lymph glands.

Hemorrhagic disorders

Excessive bleeding can result from

(1) Increased fragility of vessels,

(2) Platelet deficiency or dysfunction, and

(3) Derangement of coagulation, alone or in combination.

Common laboratory tests used in the evaluation of a

bleeding disorders are the following:

Screening tests: Bleeding Time

Complete blood count (CBC)

Prothrombin Time

Activated partial thromboplastin time

Thrombin Time

Fibrinogen activity test

Tests of Hemorrhagic Disorders

BLEEDING TIME

Bleeding time

oBleeding time - The time when the incision is made until

all bleeding has stopped is measured and is called the

bleeding time.

o Used to assess platelet function.

oA prolonged bleeding time may be a result from decreased

number of thrombocytes or impaired blood vessels.

o However, the depth of the puncture or incision may be the

source of error.

Methods

Duke Methodo With the Duke method, the patient is pricked with a needle

or lancet, on fingertip, after swabbed with alcohol.

o The prick is about 3–4 mm deep.

o Every 30 seconds, filter paper or a paper towel is used to

wipes the blood .

o Normal values- is about 2–5 minutes.

Ivy method

In the Ivy method, the blood pressure cuff is placed on

upper arm and inflated to 40 mmHg.

A lancet is used to make a shallow incision on the

underside of the forearm.

Every 30 seconds, filter paper or a paper towel is used

to draw off the blood.

Normal values - 3 – 10 minutes

Interpretation

Bleeding time is affected by platelet function, certain vascular

disorders and von Willebrand Disease—not by other coagulation

factors such as hemophilia.

Diseases that cause prolonged bleeding time include

Thrombocytopenia,

Disorders of platelet function

Disseminated intravascular coagulation (DIC),

Acute Leukemia

Aplastic anemia

Liver diseases

Aspirin and other cyclooxygenase inhibitors can

prolong bleeding time significantly.

While warfarin and heparin have their major effects on

coagulation factors, an increased bleeding time.

People with von Willebrand disease usually experience

increased bleeding time, as von Willebrand factor is a

platelet adhesion protein, but this is not considered an

effective diagnostic test for this condition.

Complete blood count (CBC)

Complete blood count (CBC)RBC count

WBC count

The total amount of hemoglobin in the blood

The fraction of the blood composed of red blood cells

(hematocrit)

The platelet count. 

The CBC test also provides information about:

Average red blood cell size (MCV)

Hemoglobin amount per red blood cell (MCH)

The amount of hemoglobin relative to the size of cell

(hemoglobin concentration) per red blood cell (MCHC).

A complete blood count (CBC) is used to detect or monitor

many different health conditions.

Diagnose infections or allergies

Detect blood clotting problems or blood disorders, including

anemia.

Evaluate red blood cell production or destruction.

The CBC interpretation are useful in the diagnosis of

various types of anemias.

It can reflect acute or chronic infection, allergies, and

problems with blood clotting.

Normal Results

Blood counts may vary with altitude. In general, normal results are:

RBC count:

Male: 4.7 to 6.1 million cells/mcLFemale: 4.2 to 5.4 million cells/mcL

WBC count: 4,500 to 10,000 cells/mcL

Hematocrit: Male: 40.7 to 50.3%Female: 36.1 to 44.3%

Hemoglobin:

Male: 13.8 to 17.2 gm/dL

Female: 12.1 to 15.1 gm/dL

Red blood cell indices:

MCV: 80 to 95 femtoliter

MCH: 27 to 31 pg/cell

MCHC: 32 to 36 gm/dL

Abnormal Results

A high RBC or hematocrit may be due to:

Dehydration (such as from severe diarrhea)

Kidney disease with high erythropoietin production

Low oxygen level in the blood for a long time due to

heart or lung disease.

Polycythemia vera

A low RBC or hematacrit is a sign of anemia, which can result

from:

Autoimmune diseases ( lupus erythematosus or rheumatoid

arthritis)

Blood loss (hemorrhage)

Bone marrow failure ( from radiation, infection, or tumor)

Chronic kidney disease

Hemolysis (red blood cell destruction)

Leukemia and other blood cancers

Long-term infections such as hepatitis

Poor diet and nutrition, causing too little iron, folate, vitamin

B12, or vitamin B6

A lower than normal white blood cell count is called

leucopenia.

A decreased WBC count may be due to:

Autoimmune diseases (such as systemic lupus

erythematosus)

Bone marrow failure (for example, due to

infection, tumor, radiation, or fibrosis)

Disease of the liver or spleen

High numbers of WBCs is called leukocytosis.

It can result from:

Infectious diseases

Inflammatory disease (such as rheumatoid

arthritis or allergy)

Leukemia

Severe emotional or physical stress

Tissue damage (such as burns)

A complete blood count with differential WBC Count

will also include:

Neutrophil  — May indicate bacterial infection.

May also be raised in acute viral infections.

Eosinophilic — Increased in parasitic infections,

asthma, or allergic reaction.

Basophil  — May be increased in bone marrow related

conditions such as leukemia or lymphoma.

Lymphocytes — Higher with some viral infections such as

glandular fever and raised in chronic lymphocytic leukemia

(CLL). Can be decreased by HIV infection.

Monocytes — May be raised in bacterial infection,

tuberculosis, malaria, Rocky Mountain spotted fever, monocytic

leukemia, chronic ulcerative colitis and regional enteritis .

Platelet counts

These are obtained on anticoagulated blood using an

electronic particle counter.

The reference range is 1.5 to 4 lac platelets/mm3.

Bleeding resulting from thrombocytopenia is associated

with a normal PT and PTT.

NORMAL 100,000 - 400,000 Cells/mm3

< 100,000 Thrombocytopenia

50,000 - 100,000 Mild Thrombocytopenia

< 20,000 SevereThrombocytopeniaSpontaneous bleeding

Bleed after major trauma

Bleed after minor trauma

Counts well outside this range should be confirmed

by a visual inspection of a peripheral blood smear,

since clumping of platelets can cause

“thrombocytopenia” during automated counting,

and high counts may be indicative of a

myeloproliferative disorder, such as essential

thrombocythemia.

Increase platelet counts can be due to :

Essential (primary)

Essential thrombocytosis (a form of myeloproliferative

disease)

Other myeloproliferative disorders such as chronic

myelogenous leukemia, polycythemia vera, myelofibrosis

It manifests clinically with elevated platelet counts and is

separated from PCV and primary myelofibrosis based on the

absence of polycythemia and marrow fibrosis, respectively. In

those cases without tyrosine kinase mutations, causes of

reactive

thrombocytosis, such as inflammatory disorders and iron

deficiency, must be excluded before the diagnosis can be

established.

Reactive (secondary)

Inflammation

Surgery (which leads to an inflammatory state)

Hyposplenism (decreased breakdown due to

decreased function of the spleen)

Splenectomy

Iron deficiency anemia or hemorrhage

Decreased platelet counts can be due to

Idiopathic thrombocytopenic purpura

Thrombotic thrombocytopenic purpura

Disseminated intravascular coagulation

Systemic lupus erythematosus

Vitamin B12 or folic acid deficiency

Leukemia or myelodysplastic syndrome

Sepsis, systemic viral or bacterial infection

chemotherapy drugs

Valproic acid, Methotrexate, Interferon,Isotretinoin

Tests of platelet functionAt present, no single test provides an adequate

assessment of the complex functions of platelets.

One older test, the bleeding time, which measures the

time taken for a standardized skin puncture to stop

bleeding, has some value but is time-consuming,

difficult to perform well, and not a good predictor of

bleeding during haemostatic stresses such as surgery.

As a result of these limitations, the use of the bleeding

time has declined considerably in recent years.

Newer instrument-based assays designed to measure platelet

function under conditions of high shear stress show promise

but at present are also less than ideal screening tests.

Other specialized tests that can be useful in particular clinical

settings include

Tests of platelet aggregation, which measure the ability

of platelets to aggregate in response to agonists like

thrombin; and quantitative and qualitative tests of von

Willebrand factor, which play an important role in platelet

adhesion to the extracellular matrix.

More specialized tests are available to measure the levels of specific clotting factors, fibrinogen, fibrin split products, and the presence of circulating anticoagulants.

Tests of blood coagulation

Routine tests of blood coagulation, such as the

Prothrombin time (PT),

Activated partial thromboplastin time (aPTT), and

Thrombin time (TT)

are frequently ordered to assess clotting function in

patients.

Prothrombin time (PT)

oThe prothrombin time is the time it takes plasma to clot

after addition of tissue factor.

oThis measures the quality of the extrinsic pathway (as well

as the common pathway) of coagulation.

oThey are used to determine the clotting tendency of blood,

in the measure of warfarin dosage, liver damage, and

vitamin K status.

Prothrombin time (PT)

oPT measures factors I (fibrinogen), II (prothrombin),

V, VII, and X.

o It is used in conjunction with the activated partial

thromboplastin time (aPTT) which measures the

intrinsic pathway.

oNormal range

oThe reference range for prothrombin time is usually

around 12-13 seconds, and the INR in absence of

anticoagulation therapy is 0.8-1.2.

Interpretation

•The prothrombin time can be prolonged as a result

of Deficiencies in vitamin K,

• warfarin therapy,

•Malabsorption, or lack of intestinal colonization by

bacteria (such as in newborns).

•Poor factor VII synthesis (due to liver disease) or

•Increased consumption (in disseminated

intravascular coagulation) may prolong the PT.

•The INR is typically used to monitor patients on

warfarin or related oral anticoagulant therapy.

•The normal range of INR for a healthy person not

using warfarin is 0.8–1.2 sec., and for people on

warfarin therapy 2 –3 sec.

•High INR indicates a higher risk of bleeding, while a low

INR suggests a higher risk of developing a clot.

Activated partial

thromboplastin time (APTT)

oThe partial thromboplastin time (PTT) or activated

partial thromboplastin time (aPTT or APTT) test

assesses both the intrinsic and common clotting

pathways.

The clotting of plasma after addition of kaolin, cephalin, and

Ca [2] + ions is measured in seconds.

Kaolin activates the contact dependent factor XII, and

cephalin substitutes for platelet phospholipids.

ACTIVATED PARTIAL THROMBOPLASTIN TIME

oApart from detecting abnormalities in blood clotting,it is

also used to monitor the treatment effects with heparin,

a major anticoagulant. It is used in conjunction with the

prothrombin time (PT) which measures the extrinsic

pathway.

o Prolongation of the PTT can be due to deficiency or

dysfunction of factors V, VIII, IX, X, XI, or XII,

prothrombin, or fibrinogen.

•Interpretation

•The typical reference range is between 30 seconds and 50

s.

•Shortening of the PTT is considered to have little clinical

relevance, but it might increase risk of thromboembolism.

•Normal PTT times require the presence of coagulation

factors:

• I, II, V, VIII, IX, X, XI, & XII.

•Deficiencies in factors VII or XIII will not be detected with

PTT test.

•Prolonged APTT may indicate:

•use of heparin (or contamination of the sample)

•Antiphospholipid antibody (especially lupus

anticoagulant, which paradoxically increases propensity

to thrombosis)

•coagulation factor deficiency (e.g. hemophilia)

•Sepsis - coagulation factor consumption

•Presence of antibodies against coagulation factors

(Factor inhibitors)

Mixing testPatient plasma

Normal plasma

PTT

Correctable PTT Factor deficiency

• If the abnormality does not disappear, the sample is said to

contain an "inhibitor" (either heparin, antiphospholipid

antibodies or coagulation factor specific inhibitors), while if it

does correct a factor deficiency is more likely.

THROMBIN TIME

•The thrombin time (TT), measures the time it takes

for a clot to form in the plasma of a blood sample

containing anticoagulant, after an excess of thrombin

has been added.

•It is used to diagnose blood coagulation disorders and

to assess the effectiveness of fibrinolytic therapy.

•This test is repeated with pooled plasma from normal

patients.

Thrombin time

•The difference in time between the test and the

'normal' indicates an abnormality in the conversion of

fibrinogen to fibrin.

•Normal values for thrombin time are 12 to 14 seconds.

•Thrombin time can be prolonged by heparin, fibrin

degradation products, factor XIII deficiency, and

fibrinogen deficiency or abnormality.

FIBRINOGEN ACTIVITY

TEST

A fibrinogen activity test is ordered as part of an

investigation of a possible bleeding disorder or

thrombotic episode.

It may be ordered as a follow-up to an abnormal

Prothrombin Time (PT) or Partial Thromboplastin Time

(PTT) and/or an episode of prolonged or unexplained

bleeding.

FIBRINOGEN ACTIVITY TEST

•It may be measured, along with tests such as PT, PTT,

platelet function tests, fibrin degradation products (FDP),

and D-dimer to help diagnose disseminated intravascular

coagulation (DIC) or abnormal fibrinolysis.

•Fibrinogen activity test is ordered to help monitor the

status of a progressive disease (such as liver disease) over

time.

•Sometimes this test is ordered, along with other cardiac

risk markers such as C-reactive protein (CRP), to help

determine a person's overall risk of developing

cardiovascular disease.

• Fibrinogen levels can be measured in venous blood.

• Normal levels are about 1.5-3 g/L, depending on the

method used.

• Higher levels are, amongst others, associated with

cardiovascular disease (>3.43 g/L).

• It may be elevated in any form of inflammation, as it is

an acute-phase protein; for example, it is especially

apparent in human gingival tissue during the initial

phase of periodontal disease.

•Low levels of fibrinogen can indicate a systemic

activation of the clotting system, with consumption of

clotting factors faster than synthesis.

• This excessive clotting factor consumption condition

is known as disseminated intravascular coagulation or

"DIC.“

• In DIC low fibrinogen levels with prolonged clotting

times (PT or aPTT), in the context of acute critical

illness such as sepsis or trauma.

Fibrinogen levels are increased in:

Increasing age

Female sex, pregnancy, oral contraception

In post-menopausal women

Acute phase reaction

Disseminated malignancy

Fibrinogen levels are reduced in:

DIC due the the consumption of clotting factors.

Liver disease due to decreased synthesis.

Massive transfusion

Inherited deficiencies e.g. Hypofibrinogenaemia,

afibrinogenaemia and dysfibrinogenaemia

Following thrombolytic therapy

In some patients following treatment with asparaginase

FACTOR ASSAYS TESTS

Clotting Factor Tests

Clotting factor tests, also called factor assays, are required to diagnose a bleeding disorder.

This blood test shows the type of hemophilia and the severity.

It is important to know the type and severity in order to create the best treatment plan.

Haemophilia A and Haemophilia B:

Activated partial thromboplastin time (APTT); prolongation depends on the severity of the factor deficiency.

Prolonged APTT plus prolonged bleeding suggests von Willebrand's disease

factor VIII clotting assay - low levels in Haemophilia A

factor IX clotting assay - low levels in Haemophilia B

In severe cases of Haemophilia B whole blood coagulation time is increased

The severity of vWD varies and many patients will never

be diagnosed, as their disorder may never come to light.

In practice - both primary and secondary - the patients

with more severe forms of the disorder will present with

abnormal bleeding.

Following this, basic blood tests including FBC, clotting

screen and liver function should be performed and

patients should be referred for a specialist opinion and

other more specialised investigations such as plasma

levels of vWf.

Plasma levels of vWF – Deficiency can be quantitative

or qualitative.

Quantitative deficiency - detected by vWF antigen

assay.

Qualitative deficiency - detected by a number of

methods including glycoprotein binding assay,

ristocetin cofactor activity, ristocetin-induced platelet

agglutination.

Factor VIII measurement:

Factor VIII binds to vWF which in turn prevents the rapid

breakdown of factor VIII; thus, a deficiency of vWF can

also lead to deficiency of factor VIII.

In type 2 vWF - factor VIII levels are normal; studies of

platelet aggregation with sub-endothelium are

necessary.

Oestrogens, vasopressin and growth hormone all

elevate levels.

These include assays of factor VIII, von Willebrand factor

antigen, von Willebrand factor activity (measured by the

ristocetin cofactor assay), and template bleeding time. In

von Willebrand disease the defect is in von Willebrand

factor.

The affected individual may have subnormal levels of

structurally and functionally normal von Willebrand factor

(this is called "classic" or type I von Willebrand disease) or

may produce von Willebrand factor that is structurally and

functionally abnormal (von Willebrand disease type 2).

Individuals who inherit a gene for von Willebrand disease from both parents have severe (type 3) von Willebrand disease and will have extremely low levels (< 3%) of von Willebrand factor and factor VIII and will have a very prolonged bleeding time.

In most populations type I disease is the most common form, whereas type 3 is the least commonly encountered form.

It should be noted that levels of von Willebrand factor can be influenced by the patient's blood type (persons who have blood type AB have 60% to 70% higher levels than do persons who have blood type O) and can be elevated during pregnancy, stress, and hyperthyroidism.

Disseminated intravascular coagulation

Diagnosis is usually suggested by-

Severe cases with hemorrhage:

The PT and APTT are usually very prolonged and the

fibrinogen level markedly reduced.

High levels of fibrin degradation products, including D-dimer.

There is severe thrombocytopenia.

The blood film may show fragmented red blood cells

(schistocytes).

Mild cases without bleeding:

There is increased synthesis of coagulation factors

and platelets.

PT, APTT, and platelet counts are normal.

Fibrin degradation products are raised.

Clinical assessment, pertinent history, and family

history are good indicators for determining

patient's bleeding tendencies.

The most appropriate laboratory tests performed

are Routine screening tests include a complete

blood cell count, platelet count, and evaluation of a

peripheral blood sample, a prothrombin time, and

an activated partial thromboplastin time.

Summary

References Kumar, V., & Robbins, S. L. 1. (2007). Robbins basic pathology (8th

ed.). Philadelphia, PA: Saunders/Elsevier.

Hoffman Hematology: Basic Principles and Practice. 5th ed. Philadelphia, Pa: Churchill Livingstone Elsevier; 2008:chap 121.

Kessler C. Hemorrhagic disorders: Coagulation factor deficiencies. In: Goldman L, Ausiello D, eds. Cecil Medicine. 23rd ed. Philadelphia, Pa: Saunders Elsevier;2007:chap 180.

Hoffbrand AV, Pettitt JE (1999). Essential Haematology. Blackwell Scientific Publications, Oxford.