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Seminar Presentation on;
Approach to Bleeding Disorders In
Pediatrics Patient
By
Alemu A, Amdu T & Aregahegn T
Ambo University
Collage Of Medicine & Health Sceince
Department Of Medicine
Sep,10/2014
Outline
Over view of homeostasis and the blood
clotting process.
Over view of some bleeding disorders in
pediatrics patient
Approach to a child with bleeding disorder.
Lab investigations
Interpretation of lab. tests & clinical
Introduction
Normal hemostasis Mechanism by which bleeding from an injured vessel is arrested by
formation of a thrombus.• Functions
To maintain the blood in fluid state To prevent clots in intact vessels To arrest bleeding in injured vessels
• Components Blood vessels Platelets Plasma coagulation factors Fibrinolytic system
STAGES OF HEMOSTASIS
INJURY
VESSEL WALL+PLATELET
FORMATION OF PLT PLUG
ACTIVATION OF PLASMA COAGULATION FACTORS
FORMATION OF STABLE FIBRIN CLOT
DISSOLUTION OF FIBRIN CLOT BY FIBRINOLYSIS
PRIMARY
SECONDARY
Cont’d
PRIMARY
Platelet & vessel wall mediated
Occurs within seconds of injury
Forms Platelet plug
Prevent blood loss from capillary , arterioles and venules
SECONDARY
Coagulation factors mediated
Takes several minutes for
completion
Forms stable fibrin plug
Prevents blood loss from large
vessels
Cont’d
Cont’d
Cont’d
Cont’d
Bleeding Bleeding or hemorrhaging, is the escape of blood from the circulatory
system.
Bleeding can occur
– internally, where blood leaks from blood vessels inside the body, or
–externally, either through a natural opening such as the mouth, nose,
ear, urethra, vagina or anus, or through a break in the skin.
It is then inferred that the bleeding is due to a functional impairment of the normal hemostatic process.
Cont’d
This impairment may be due to
1. A functional deficiency in the procoagulant
mechanism. This may involve
a. The platelets
b. The procoagulant plasma components
Cont’d
2. A functional excess in anticoagulant
mechanisms.
a. Anticoagulant drugs
b. Natural anticoagulants
3. A functional excess in the fibrinolytic
mechanism.
CAUSES OF BLEEDING
Vessel wall disorders
Platelet disorders: quantitative or
functional.
Coagulation factor: deficiency or inhibitors.
Combination of these.
VASCULAR DISORDERS
ACQUIRED CONGENITAL
•Senile purpura
•Vascular purpura
•Henoch schonleinpurpura
•Hereditary hemorrhagic telengiectasia
•Ehlers danlossyndrome
telengiectasia
Senile purpura
PLATELET ABNORMALITIES
QUALITATIVE QUANTITATIVE
•THROMBASTHENIA
•BERNARD-SOULIER SYNDROME
•DRUGS(ASPIRIN,IND-OMATHACIN
•THROMBOCYTOPENIA
•THROMBOCYTHEMIA
Petechia
•
Purpura
DISORDERS OF COAGULATION F
Hereditary haemophilia A (factor VIII deficiency)
haemophilia B (factor IX deficiency)
von will brand disease
Disorders of fibrinogen-
Hereditary afibrinogenaemia
hypofibrinogenaemia
Dysfibrinogenaemia
Acquired Disseminated intravascular coagulation(DIC)
Liver disease
Vit k deficiency
Massive transfusion of stored blood
Acquired inhibitors of coagulation
Heparin or oral anticoagulant therapy
Renal disease
Hemophilia A
Massive hemorrhage in the
area of right buttock
Hemophilia A
Gross swelling from acute
haemarthroses of the
knee joints
DIC
Classification of Disorders of Hemostasis
Major Types Disorders Examples
Acquired Thrombocytopenia's
Autoimmune and alloimmune, drug-induced, hypersplenism, hypoplastic (primary, myelosuppressivetherapy, myelophthisic marrow infiltration), disseminated intravascular coagulation (DIC), thrombotic thrombocytopenic purpura, hemolytic-uremic syndrome
Liver diseases Cirrhosis, acute hepatic failure, liver transplantation ,
Vitamin K deficiency
Malabsorption syndrome, hemorrhagic disease of the newborn, prolonged antibiotic therapy, malnutrition, prolonged biliary obstruction
Hematologic disorders
Acute leukemia's , myelodysplasias, monoclonal gammopathies, essential thrombocythemia
Major Types Disorders Examples
Acquired Acquired antibodies against coagulation factors
Neutralizing antibodies against factors V, VIII, and XIII, accelerated clearance of antibody-factor complexes, e.g., acquired von Willebrand disease, hypoprothrombinemia associated with antiphospholipid antibodies
DIC Acute (sepsis, trauma, obstetric complications) and chronic (malignancies, giant hemangiomas, retained products of conception)
Drugs Antiplatelet agents, anticoagulants, antithrombins, and thrombolytic, hepatotoxic, and nephrotoxic agents
Vascular Non-palpable purpura ("senile," solar, and factitious purpura), use of corticosteroids, vitamin C deficiency, thromboembolicPalpable-purpura -Henoch-Schönlein, vasculitis
Clinical features
• Epistaxis-symptoms of platelet disorders & vWD
• Gingival hemorrhage- platelet disorders & vWD
• Oral mucous membrane bleeding- severe
thrombocytopenia
• Skin hemorrhage ( petechiae and ecchymoses)-common manifestations of hemostatic & non-hemostatic disorders
• Hemarthroses- hallmark abnormality in the hemophilia’s, severe factor VII deficiency and type 3 von Willebrand disease
Cont’d• Easy bruising- Ehlers-Danlos syndrome • Excessive bleeding in response to razor nicks =platelet
disorders or von Will brand disease.• Hemoptysis- haemostatic disorders in URT.• Hematemesis- haemostatic disorders in upper GI• Hematuria- hemophilia's & haemostatic disorders• Rectal bleeding -in normal-hemorrhoids- von
Willebrand disease and platelet disorders • Melena• Postpartum hemorrhage -DIC• Habitual spontaneous abortions- quantitative or
qualitative abnormality of fibrinogen.
DIAGNOSIS OF BLEEDING DISORDERS
• HISTORY
• CLINICAL EXAMINATION
• LABORATORY INVESTIGATIONS
History taking
On Hx– Site or sites of bleeding,
– The severity and duration of hemorrhage, and
– The age at symptom onset.
– Spontaneous or after trauma?
– Does bruising occur spontaneously?
– Previous personal or family history of similar
problems?
– Recent transfusion?
Cont’d
– A history of anemia and/or previous treatment with iron
– Joint pain, swelling or limitation of movement
– Bleeding from umbilical stump
– Previous surgery or significant dental procedures,
was there any increased bleeding?
– Delayed or slow healing of superficial injuries
suggest a hereditary bleeding disorder
Cont’d
– Menstrual history (in post pubertal females)
– Medications ( NSAIDs, anticonvulsant , anti TB,
antihistamin, or herbal medications
cause thrombocytopenia
– Nutritional Hx to assess the likelihood of vt k & C deficiency and general malnutrition and/or malabsorption
Physical Examination
On PH/E
• We can look for the presence of
– Petechiae , ecchymoses , hematomas,
hemarthroses, or mucous membrane bleeding.
defects in platelet/blood vessel wall interaction
– fixed drug eruption, erythema nodosum, viral
exanthem and mosquito bites
Cont’d
• Look for hepatosplenomegaly
• Do a rectal exam for evidence of GI bleeding
• Look for physical signs and symptoms of diseases
related to capillary fragility:
– Petechiae secondary to coughing, sneezing, Valsalvamaneuver, blood pressure measurement
Cont’d
• If there is bleeding is it localized or generalized?
– Localized- single site
– Generalized
• Is it platelet type or coagulation type of bleeding?
• Is it congenital/hereditary or acquired disorder?
• Symptoms of a longer duration are indicative of a congenital
disorder such as von Will brand Disease (vWD) or
coagulation-factor deficiencies
Cont’d
36
Cont’d
37
Cont’d
38
Cont’d
NB. – Petechiae are pathognomonic of platelet-related
bleeding
– Deep tissue and intramuscular bleeds should prompt the diagnosis of a coagulation factor deficiency
– Patient with a clotting factor VIII or factor IX deficiency have deep bleeding into muscles and joints with much more extensive ecchymoses and hematoma formation.
Laboratory Evaluation
1st line investigation
– Test for platelets
• Platelet count
• Bleeding Time(BT)
– Test for coagulation factors• Prothrombin Time(PT)
• Activated Partial Thromboplastin Time(aPTT)
• Thrombin Time(TT)
• Fibrinogen assay
Lab. exam
Bleeding Time (BT)
Significance
• Assess primary haemostatic defect
– vessel wall or platelet interaction.
• Dependent on adequate functioning of
– Platelets
– Blood Vessels.
Range
• 4-8 min
Cont’d
Interpretation
Causes of prolonged BT
• Thrombocytopenia
• VWD
• Platelet function disorder
• Disorder of blood vessels.
Cont’d
Prothrombin Time(PT)Significance• Reflects overall activity of the Extrinsic Pathway.
• Most sensitive to changes in Factor V,VII,X.
• Lesser to Factor I & II.
Principle• Platelet poor plasma + Tissue Thromboplastin + Calcium
• In Presence of F VII Extrinsic pathway is activated & clot
formed
Normal Range
• 10-12 seconds (with human thromboplastin)
Cont’d
Interpretation
Causes of prolonged PT
1. Deficiency of Factor VII,X,V,II,I
2. Vit K deficiency
3. Liver disease
4. Oral anticoagulants
Cont’d
Activated Partial Thromboplastin Time (aPTT)Significance
• Reflects efficiency of Intrinsic Pathway.
• Sensitive to changes in Factor VIII,IX,XI,XII.
• Also sensitive to heparin & circulating anticoagulants.
The test measures the clotting time of plasma after the
activation of contact .
So it indicates the overall efficiency of the Intrinsic
pathway
Normal range
26 to 40 seconds.
Cont’d
Interpretation
Causes of prolonged aPTT
1. Deficiency of Factor VIII (Haemophilia A).
2. Deficiency of Factor IX (Haemophilia B).
3. Heparin therapy.
4. Circulating anticoagulants.
5. Liver disease.
Cont’d
Thrombin Time(TT)
Significance• Asses the final step of coagulation, i.e. conversion of fibrinogen to
fibrin in presence of thrombin.
• Bypasses Extrinsic & Intrinsic pathway.
Principle• Thrombin is added to plasma and the clotting time is
measured.
• TT is affected by the concentration and reaction
of fibrinogen and by the presence of inhibitory substances.
Normal range• 15–19 sec, Times of 20 s and longer are definitely abnormal.
Cont’d
Interpretation
Causes of prolonged TT
1. Disorders of fibrinogen-
Afibrinogenaemia.
Hypofibrinogenaemia
Dysfibrinogenaemia.
2. Liver disease.
3. heparin therapy
Cont’d
2nd line investigations
Carried out with each of the patterns of abnormalities in first line tests
1. Mixing test.
2. Factor VII assay.
3. Liver function test.
Cont’d
Mixing test
– If prolong. PT, PTT, or TT
Normal plasma + patient's plasma, and the PT or PTT is repeated.
• Correction of PT or PTT => def. of a clotting factor, (because a 50% level of individual clotting proteins is sufficient to produce normal PT or PTT.)
Cont’d
• If the clotting time is not corrected or only partially corrected, an inhibitor
– chemical similar to heparin that delays coagulation or
– an antibody directed against a specific clotting factor.(MC- VIII, IX, or XI, may be present) or
– the phospholipids used in clotting tests is usually present
Summary of Interpretation of lab. tests & clinical
• Intrinsic
Interpretation cont’d
• Extrinsic
Interpretation cont’d• Common
Reference
Nelson textbook of pediatrics ,19th edition
Current diagnosis and treatment inpediatrics,20th edition
Pediatrics and child health lecture note forhealth sceince students ,jimma university