Chapter 25 Disorders of Plasma Clotting Factors Flashcards Preview

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Flashcards in Chapter 25 Disorders of Plasma Clotting Factors Deck (32):
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•Disorders of primary hemostasis include abnormalities that clinically result in bleeding due to defect of an _______?

•Disorders of primary hemostasis include abnormalities that clinically result in bleeding due to defect of an adequate platelet plug

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•Clinical Manifestations of Disorders of primary hemostasis include

•Clinical Manifestations

•Ecchymosis (a discoloration of the skin resulting from bleeding underneath, typically caused by bruising.)

Petechiae

Purpura

•Mucosal Bleeding

Gingival bleed

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Quantiative Congenital Thrombocytopenias 

•Congenital

•May-Hegglin Anomaly

•Bernard-Soulier syndrome

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Quantiative Acquired Thrombocytopenias 

•Drug effect

•Radiation Therapy

•Aplasia

•Megaloblastosis

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Quantitative Thrombocytopenia that •results in platelet sequestration in giant hemangiomas (A birthmark often appearing as a rubbery, bright red nodule of extra blood vessels.)

Abnormal Distributed thrombocytopenia

•Kasabach-Merritt Syndrome

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Abnormal Distribution thrombocytopenia Causes of •Splenomegaly?

•Causes: Hematologic malignancies, liver cirrhosis, and portal vein thrombosis

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•Most common disorders causing severe isolated thrombocytopenia

•Caused by an antibody to the patient’s platelets

•Typically a diagnosis of exclusion ( no specific test currently available)

•Idiopathic (Immune)Thrombocytopenic Purpura (ITP)

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•Commonly presents in the 20 -50 year old

•Female predominance 3:1

•Common Clinical Findings:

•BM- increase to normal numbers of megakaryocytes

•Shorten platelet life span; circulating plts morphologically large on smear

Adult Idiopathic Thrombovytopenic Purpura

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•Sudden onset of TCP occurring approximately 1 week after transfusion of blood or blood products containing platelets

•Post-transfusion Purpura (PTP)

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PTP •Majority of cases are result of an alloantibody directed against platelet antigen _____? (aka: HPA-1a)

•Majority of cases are result of an alloantibody directed against platelet antigen PI A1 (aka: HPA-1a)

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•Reported in multiparous women

•Post-transfusion Purpura (PTP)

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•PI A1 antigen is found in approximately ___% of the normal population

•__% who lack PI A1 antigen on their platelets are considered at risk for developing PTP

•PI A1 antigen is found in approximately 97% of the normal population

3% who lack PI A1 antigen on their platelets are considered at risk for developing PTP

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•Results from immunization of the mother by fetal platelet antigens and placental transfer of maternal antibody

•Most often caused by maternal antibodies to the PlA1

•Uncommon disorder, generally affects first-born child

•Isoimmune Neonatal Thrombocytopenia

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•Isoimmune Neonatal Thrombocytopenia Lab Findings?

•Appear normal at birth, shortly after (within hours) develop scattered petechiae and purpuric hemorrhages

•Platelet count below 30 X 109 /L

•Intercranial hemorrhage- primary cause of death

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•Non-Immunologic

•Microangiopathic Thrombocytopenia

•Characteristic pathologic feature- Hyaline microthrombi found in multiple organs

•Thrombotic Thrombocytopenic Purpura (TTP)

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Thrombotic Thrombocytopenia Purpura Lab Features

•Laboratory Features

•Severe microangiopathic hemolytic anemia w/ schistocytes, reticulocytosis, and nucleated red blood cells

•Hemoglobinemia

•Hemoglobinuria

•Bleeding time- increased

•PT, APTT, fibrinogen, and D-dimer- normal

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•Non-Immune Thrombocytopenia

•Characterized by microangiopathic hemolytic anemia ((loss of red blood cells through destruction) caused by factors in the small blood vessels) , tcp, and renal failure

•Commonly seen in the pediatric population

•Pathogenic thrombi are limited to the glomerular capillaries and afferrent arterioles of the kidney.

•Hemolytic Uremic Syndrome

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•Hemolytic Uremic Syndrome prognosis is worse in adults or children?

•Prognosis is worse in adult onset vs. children onset HUS

•Increase mortality rate

•Increased incidence of long-term morbidity from permanent renal damage

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•Other non-Immunologic quantiative Thrombocytopenias

•Heparin-Induced Thrombocytopenia and Thrombosis

•Disseminated Intravascular Coagulation (DIC)

•Also known as: Consumption Coagulopathy

•Bacterial, viral, or rickettsial infections

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•Platelet count above the normal range ( >450,000/μ)

•Due to:

•Primary myeloproliferative disorder (MPD)

•Reactive process

•Thrombocytosis

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•Polycythemia Vera, CML, MPD

•Essential Thrombocythemia

•Have the highest platelet count (exceeding 1000 X 109 /L)

•PrimaryThrombocytosis (1o)

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•Plts are responding to something going on in the body

•May be a transient or chronic process

•Reactive Thrombocytosis (2o)

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•Reactive Thrombocytosis (2o) causes:

•Acute hemorrhage (most common)

•Post-splenectomy

•Oral contraceptives

•Infections

•Underlying malignancies

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•Congenital Disorders of Platelet Function

•Based on platelet function or abnormal response

Classified by?

1.Platelet surface membrane defects

2.Platelet release or secretion defects

3.Platelet coagulant activity defects

4.Defects associated with abnormal platelet-coagulant protein interactions

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•Autosomal-recessive disorder of platelet function

•Caused by an absence or deficiency of the membrane GPIIb/IIIa complex

Qualitative Disorder

•Glanzmann’s Thrombasthenia

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•Autosomal-recessive bleeding disorder

•Caused by a deficiency of the platelet GPIb/IX complex

•GPIb/IX Complex

•Bernard-Soulier Syndrome

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•Involved in the vWF-dependent contact adhesion of unactivated platelets to exposed subendothelium at high shear rates and for the binding of platelets to fibrin

•Serves as a high-affinity thrombin binding site

•Regulates platelet shape and reactivity

GPIB/F IX complex

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•primarily involved in absence of platelet granules or defective enzymatic pathways

•Platelet Release(Secretion Defects)

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•Classified according to an analysis of the granule proteins and the morphological appearance of the platelets

•Characterized by decreased amounts of secreteable ADP, ATP, calcium, and serotonin

•Decrease in platelet dense granules present

•Laboratory Findings

•Storage Pool Disease (Granule Defects) (ex. Chediak Higashi)

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•deficiencies of enzymes and other “second messengers” that transmit the signal from surface receptors to cause platelet release of granule contents

•Primary Secretion Defects ( Enzymatic Pathway Defects)

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•Originally termed parahemophilia

•May be confused with primary platelet defects due to the similarities in clinical presentations

•von Willebrand Disease

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