Abnormal Hematology Exam #4
A laboratory test that would be abnormal in a patient with afibrinogenemia but normal in a patient with hypofibrinogenmia or dysfibrinogenemia would be what?
bleeding time
In von Willebrand disease you will expect to see a prolonged: Bleeding time and PT PT and APTT Clot retraction Bleeding time and APTT Rumple-Leed and bleeding time
Bleeding time and APTT
The 1:1 patient mix is performed by adding equal amounts of patient plasma and normal plasma. The APTT clotting time is prolonged. This is suggestive of what?
Circulating inhibitor
What is the major function of Vitamin K in hepatic cells?
Hepatic cells need Vitamin K to carboxylate: - Factors: II, X, VII, IX (2, 10, 7, 9) - Protein C - Protein S
What is seen on the PBS of a patient with Gray Platelet Syndrome?
Hypogranular "grey" platelets - due to lack of alpha granules
When performing an aggregation study, a sample has an abnormal RIST result that is corrected with the addition of vWF. What condition does this support?
vWD
Why can Factor VIII function be abnormal in cases of vWD?
vWF acts as a carrier of FVIII
Name some factors that influence vWF levels.
vWF is an acute phase reactant *Increased levels of vWF are associated with:* Aging Exercise Inflammation Stress Pregnancy/estrogen level Liver disease Hyperthyroidism *Decreased levels of vWF are associated with:* Blood group O Hypothyroidism
Explain the mechanism of Heparin associated thrombocytopenia (HAT).
Nonimmune-mediated - Heparin causes direct activation of platelets
State the what the expected test results would be of a primary hemostasis quantitiave platelet disorder. PLT #: PT: aPTT: Bleeding Time: PFA-100 Assay:
PLT #: decreased PT: normal aPTT: normal Bleeding Time: abnormal PFA-100 Assay: abnormal
State the what the expected test results would be of a primary hemostasis vascular disorder. PLT #: PT: aPTT: Bleeding Time: PFA-100 Assay:
PLT #: normal PT: normal aPTT: normal Bleeding Time: normal/abnormal PFA-100 Assay: normal
State the what the expected test results would be of a primary hemostasis qualitative platelet disorder. PLT #: PT: aPTT: Bleeding Time: PFA-100 Assay:
PLT #: normal (usually) PT: normal aPTT: normal Bleeding Time: abnormal PFA-100 Assay: abnormal
Which of the following tests would be expected to be abnormal in a patient with a Factor VII deficiency? PLT # Bleeding Time PT aPTT TT 5M Urea
PT
Which of the following tests would be expected to be abnormal in a patient with a Factor II deficiency? PLT # Bleeding Time PT aPTT TT 5M Urea
PT aPTT
Which of the following tests would be expected to be abnormal in a patient with a Factor V deficiency? PLT # Bleeding Time PT aPTT TT 5M Urea
PT aPTT
Which of the following tests would be expected to be abnormal in a patient with a Factor X deficiency? PLT # Bleeding Time PT aPTT TT 5M Urea
PT aPTT
Can a patient have a mixture of both a deficiency in alpha and dense storage pool granules in their platelets?
Yes
Platelet aggregation studies in von Willebrand's disease will show: a) Abnormal aggregation with ristocetin b) Abnormal aggregation with epinephrine c) Abnormal aggregation with ADP d) Abnormal aggregation with collagen e) Normal aggregation with all of the above agonists
a) abnormal aggregation with ristocetin
Which of the following tests would be expected to be abnormal in a patient with a Factor IX deficiency? PLT # Bleeding Time PT aPTT TT 5M Urea
aPTT
Which of the following tests would be expected to be abnormal in a patient with a Factor VIII deficiency? PLT # Bleeding Time PT aPTT TT 5M Urea
aPTT
Which of the following tests would be expected to be abnormal in a patient with a Factor XI deficiency? PLT # Bleeding Time PT aPTT TT 5M Urea
aPTT
Which of the following tests would be expected to be abnormal in a patient with a Factor XII deficiency? PLT # Bleeding Time PT aPTT TT 5M Urea
aPTT
Which of the following tests would be expected to be abnormal in a patient with a Prekallikrein deficiency? PLT # Bleeding Time PT aPTT TT 5M Urea
aPTT
Explain the mechanism of post-transfusion purpura.
antibodies specific to platelets that patient has received from donor, causing thrombocytopenia
Secondary hemostasis defects may include all of the following EXCEPT: a) Production of abnormal molecules that interfere with the coagulation pathways b) Decreased synthesis of one or more factors c) Qualitative defects in platelets d) Inactivation of one more factors by inhibitors e) Loss or consumption of the coagulation factors
c) Qualitative defects in platelets
State the following expected test results for the following tests in a patient with vWD along with what each test is measuring. Bleeding Time: PFA-100: aPTT: FVIII:C: vWF: Ag: vWF: RcoF: Multimer Analysis: PLT Aggregation Studies:
*Bleeding Time:* - prolonged, PFA-100 more sensitive *PFA-100:* - abnormal, screening assay *aPTT:* - mildly prolonged/normal *FVIII:C:* - Factor VIII coagulation activity, abnormal *vWF: Ag:* - protein level of vWF, decreased or increased depending on type *vWF: RcoF:* - functionality of vWF, depends on type (increased/ decreased) *Multimer Analysis:* - electrophoretic measure of multimer size, depends on type *PLT Aggregation Studies:* - abnormal with RIST, corrected with vWF
Explain what test results would correlate with heparin contamination compared to a fibrinogen mutation/deficiency. *Bleeding Time:* *PT:* *aPTT:* *Thrombin Time:* *Retilase Time:* *Fibrinogen:*
*Bleeding Time:* normal *PT:* normal/abnormal *aPTT:* abnormal *Thrombin Time:* abnormal *Retilase Time:* normal *Fibrinogen:* normal
Name some common clinical manifestations of platelet and vascular disorders and define each.
*Bleeding from subcutaneous blood vessels into intact skin* Petechiae: small pin point bleed under skin Purpura: larger bleed under skin < 3cm Ecchymosis: >3cm bruising under skin *Mucosal bleeding* Epistaxis - nose bleeds Gingival bleeding Gastrointestinal bleeding Menorrhagia - heavy menstrual cycles Hematuria
Name some causes of vitamin K deficiency and how it is resolved along with the expected results of the following tests:
*Causes:* - Newborns - Malabsorption issues - Vitamin K inhibitors - Prolonged broad spectrum antibiotic use - Administration of Vitamin K corrects deficiency *Treatment* - Administration of Vitamin K *Lab results* PT and aPTT: prolonged 1:1 Mixes: normal (corrected) Decreased activity of vitamin K factors (II, VII, IX, X)
Describe the following characteristics of Bernard-Soulier Syndrome (BSS): Defect: Symptoms: Lab Results: PBS: BM:
*Defect:* decrease or abnormality in GP1b (inherited) - impaired adhesion to epithelium *Symptoms* - prolonged bleeding, petechiae, purpura *Lab Results:* PLT #: normal/ decreased Bleeding Time: Prolonged GP1b Flow Cyt: abnormal Platelet aggregation studies: - RIST w/ vWF: abnormal *PBS:* large platelets (>60%)
Name the three classifications of thrombocytopenias and some causes of each classification.
*Deficient Plasma Production* - aplasia, leukemias, anemias - B12 deficiency - myelodisplasia - May-Hegglin, Bernard-Soullier *Abnormal Platelet Distribution* - hypersplenism *Increased Platelet Destruction* - Immune (ITP, Heparin Induced) - MAHA (TTP, HUS, DIC) - Pregnancy associated (HELLP, preeclampsia)
State the major appropriate test results that distinguish Hemophilia A, Hemophilia B, and vWD Type 1.
*Hemophilia A:* aPTT: increased FVIII assay: decreased FXI assay: normal vWF: Ag assay: normal *Hemophilia B:* aPTT: increased FVIII: normal FXI: decreased vWF:Ag assay: normal *vWD Type 1:* aPTT: normal/increased FVIII: normal/decreased FXI: normal vWF: Ag assay: decreased
Explain the mechanism of heparin-induced thrombocytopenia(HIT), and identify laboratory results associated with this condition.
*Heparin Induced Thrombocytopenia (HIT)* Immune-mediated - Develops 4-10 days after heparin administration - Antibodies are against the heparin/platelet factor 4 (PF4) complex - Increased platelet clearance → thrombocytopenia - Antibody/heparin/PF4 complexes are capable of inducing platelet activation and aggregation
What are the inherited primary vascular disorders? State what each is associated with/caused by.
*Hereditary Hemorrhagic Telangiectasia (HHT) aka Osler-Weber-Rendu Syndrome* - linked to genetic mutations involving TGF-β signaling *Ehlers-Danlos Syndromes* - defect in collagen structure or production *Marfan Syndrome* - linked to the misfolding of a glycoprotein (fibrillin-1) which forms elastic fibers
Name the following of Glanzmann Thrombasthenia: Mechanism: Symptoms: Test Results: Criteria for Diagnosis:
*Mechanism:* - Defect in platelet aggregation due to a deficiency in the GPIIb/IIIa complex *Symptoms:* - minor bruising to life-threatening hemorrhages *Test Results:* PLT #: normal PLT morphology: normal Bleeding time: prolonged PFA-100: prolonged Flow Cyt: decreased GPIIb/IIIa PLT agg: - ADP, EPI, COL: decreased/abnormal - RIST: normal
State the following characteristics of Hemophilia B: Mechanism: Clinical Findings: Lab Results: Platelet count = PFA and platelet aggregation studies = Bleeding time = PT = APTT = 1:1 mix APTT =
*Mechanism:* Deficiency of Factor IX *Clinical Findings:* *Lab Results:* Platelet count = normal PFA and platelet aggregation studies = normal Bleeding time = normal PT = normal APTT = prolonged 1:1 mix APTT = corrected/normal FVIII assay: normal FIX assay: abnormal
What would be the expected test results of the following tests for a storage pool deficiency? PLT #: Bleeding Time: PFA-100: PT: aPTT: PLT Agg. Studies:
*PLT #:* normal *Bleeding Time:* abnormal *PFA-100:* abnormal/normal *PT:* normal *aPTT:* normal *PLT Agg. Studies:* abnormal in *δ*-Storage Pool Disease - EPI/ADP: Lack secondary wave - COL: little/no response - RIST: decreased w/ normal shape
What would be the expected results for the following tests in a case of liver disease? Platelet count = PT, APTT, TT = Fibrinogen = FDP test = Plasminogen = Antithrombin = Protein C = Protein S = Peripheral blood smear =
*Platelet count =* decreased *PT, APTT, TT =* increased *Fibrinogen =* decreased *FDP test =* normal/increased *Plasminogen =* decreased/normal *Antithrombin =* decreased *Protein C =* decreased *Protein S =* decreased *Peripheral blood smear =* macrocytes, target cells, acanthocytes
State the expected results of the following laboratory tests in a case of vWD. Platelet count = Bleeding time/PFA = Platelet aggregation tests show ADP = Epi = Collagen = Ristocetin = Ristocetin with VWF = PT = APTT =
*Platelet count* = normal *Bleeding time/PFA* = abnormal/prolonged *Platelet aggregation tests show* - ADP = normal - Epi = normal - Collagen = normal - Ristocetin = abnormal - Ristocetin w/ VWF = normal *PT* = normal *APTT* = normal/abnormal (depends on factor VIII functionality)
State the expected lab tests results for the following tests in a case of primary fibrinolysis? Platelet count PT, APTT, Thrombin time: D-dimer test is FDP test is Plasminogen is Fibrinogen is Peripheral blood smear
*Platelet count:* normal *PT, APTT, Thrombin time:* increased *D-dimer:* normal *FDP:* increased *Plasminogen:* decreased *Fibrinogen:* decreased *Peripheral blood smear:* normal
What laboratory tests are useful in the diagnosis of primary hemostatic disorders?
*Primary* PLT # PT aPTT Bleeding Time PFA-100 Assay *Other* Platelet antibody testing Platelet aggregation Bone marrow biopsy or aspirate
Describe what Type I, II, and III vWD involves.
*Type I* Most common vWF disorder - Partial deficiency in vWF (20-50% of normal levels of vWF present) - quantitative deficiency - Mild bleeding episodes seen in some patients *Type II* - Qualitative defect in vWF: dysfunctional molecule - About 30% of vWF cases - Variable inheritance with numerous different subtypes *Type III* - Very rare - very little to absolute absence of vWF - Life-threatening bleeding episodes
Name the three categories of qualitative platelet disorders, along with common symptoms that may be observed.
1) Defects in platelet-vessel wall interaction (platelet adhesion) 2) Defects in platelet-platelet interaction (platelet aggregation) 3) Defects in platelet secretion *Possible Symptoms* - mild to severe - petechiae, bruises, bleeding from mucous membranes
Give the three general categories of disorders of primary hemostasis.
1) Vascular 2) Quantitative Platelet 3) Qualitative Platelet
Which of the following tests would be expected to be abnormal in a patient with a Factor XIII deficiency? PLT # Bleeding Time PT aPTT TT 5M Urea
5M Urea
How can aspirin use be identified using platelet aggregation studies?
ADP: No secondary wave RIST: normal Arachadonic Acid: no response COL: no response
What is the defect in Glanzmann's Thrombasthenia?
Abnormal platelet aggregation, deficiency in GPIIbIIIa will see abnormal aggregation with ATP, EPI, COL, - normal with RIST
What is primary fibrinolysis associated with? What conditions?
Activation of plasminogen to plasmin in the absence of the initiation of coagulation - break down fibrin, F 5, 8, and 13 and fibrinogen - plasmin is frisky enzyme - leads to inability to clot when appropriate - Diffuse hemorrhage due to increased breakdown of fibrinogen *Due to* - increase in tPA - decreased inhibitors (antiplasmin) - some diseases *hepatic cirrhosis* and cancers
State some laboratory findings in ITP and tests that can be performed.
Antiplatelet antibody tests - measure amount of IgG bound to platelets Perform bone marrow biopsy (diagnosis of exclusion) BM: increase in megakaryocytes ELIZA: IgG abs specific for proteins MPV Increase: large/giant platelets
Explain how aspirin affects platelet function.
Aspirin ingestion prolongs the bleeding time and is dose-dependent *Mechanism of platelet dysfunction* - Aspirin irreversibly inhibits the cyclo-oxygenase enzyme preventing formation and release of thomboxane A2 from arachidonic acid - Platelet granule release is blocked and aggregation is decreased BT is increased by 1 - 2 minutes after a single dose for 7-10 days
Explain the mechanism of ITP.
Autoreactive antibodies that bind to platelets Autoantibodies to: - GPIIb/IIIa - GPIb Acute vs Chronic
Which result would be expected in a newborn infant? A) A shorter APTT test than that of an adult B) A longer APTT test than that of an adult C) A lower platelet count than that in an adult D) A higher platelet count than that in an adult
B) A longer APTT test than that of an adult
How do you distinguish between BSS and von Willebrand disease via laboratory tests?
BSS - Deficiency in GPIb - abnormal RIST not corrected with added vWF vWFD - deficiency in vWF - abnormal RIST corrected with added vWF
When performing an aggregation study, a sample has an abnormal RIST result that is not corrected with the addition of vWF. What condition does this support?
Bernard - Soulier Syndrome (BSS)
Which of the following tests would be expected to be abnormal in a patient with a vWF deficiency? PLT # Bleeding Time PT aPTT TT 5M Urea
Bleeding Time aPTT
Name some common symptoms of secondary hemostasis disorders.
Bleeding can be more profuse since larger vessels are involved Hemorrhage normally within deep muscles and/or joints = HEMATOMAS/HEMARTHROSES Delayed bleeding may also occur Symptoms present also common to primary disorders
What Clinical symptoms are commonly seen in patients with primary hemostasis disorders?
Bleeding from mucus membranes, heavy menstrual bleeds, petechiae, ecchomosis, purpura
Ingestion of aspirin will cause which of the following test results to be prolonged? Bleeding time Prothrombin time APTT Fibrinogen level Thrombin time
Bleeding time
Name some general characteristics of patients with primary vascular disorders?
Can be inherited or acquired - Inherited vascular disorders involve abnormalities in the synthesis of subendothelial connective tissue or extracellular matrix components No platelet or plasma defects Most common symptom - bleeding into or under the skin Majority of patients have hemostatic testing that is entirely normal
Describe normal hemostasis in newborns and how their test results may differ from an adult and why.
Clotting proteins do not reach adult levels until 6-12 months of age - Platelets and clotting proteins detected in fetuses at 10-11 weeks of gestation - Platelet counts reach adult levels by 27 weeks gestation Laboratory screening tests are prolonged and depend on the child's age along with accompanying diseases *Abnormal platelet aggregation studies* - DECREASED aggregation with ADP, epinephrine, and collagen due to dense granules having 50% less of the level as compared to adults of ADP and serotonin - INCREASED aggregation with ristocetin due to newborns having decreased levels of ADAMS13, so they have higher molecular weight vWF - prolonged aPTT at birth - normal PT at birth
Name some causes of acquired primary vascular disorders and some characteristics of these kinds of disorders.
Comprises disorders that result in bruising but are not associated with a specific disease Bruising often mild *Examples:* Mechanical purpura - increase in blood pressure, excessive coughing/vommiting Senile purpura - old age, decreased collagen structure/function/quantity Factitious purpura - false, self-inflicted (hickeys, sucking around a cup on mouth)
Name some general causes of secondary homeostasis defects.
Decreased production of one or more factors - Can be inherited or acquired Production of abnormal molecules that interfere with the coagulation pathways Loss or consumption of the coagulation factors Inactivation of one or more factors by inhibitors or antibodies
Name some common bleeding disorders that can be seen in "sick" babies (premature, Respiratory distress, infection).
DIC Isolated platelet consumption Liver failure Common cause of death in premature infants is intracranial hemorrhage - can be seen in babies with hemophilia
A patient presents with a platelet count of 212 x 109/L and a bleeding time of 12 minutes. These results most probably suggest which of the following? Decreased platelet production Defective platelet function Increased platelet production Increased platelet destruction Sequestration of the platelets by the spleen
Defective platelet function
The test that is useful in distinguishing between a specific factor inhibitor and a lupus-like antiphospholipid antibody is what?
Dilute Russell venom viper time
What is vWD? Name some common symptoms and the three classifications.
Disorder: - vWF is reduced, absent, or abnormal in function - inherited Symptoms: - Patients present with mucocutaneous bleeding Classifications: Type 1, 2, and 3
What is DIC? Explain the mechanism.
Disseminated Intravascular Coagulation *SYNDROME NOT DISEASE* *Mechanism* 1) trigger activates coagulation cascade and is disseminated 2) Thrombus is formed due to activation of clotting factors 3) Fibrin deposits are formed within the capillaries, venules, and arterioles 4) Fibrin formation leads to consumption and depletion of factors 5) Platelets trapped in fibrin mass 6) Schistocytes formed due to shearing when hitting clots 7) Numerous hemostatic proteins become depleted
Patients with a prolonged bleeding time and a prolonged APTT are likely to have which of the following hemostasis disorders: A) Glanzmann's thrombasthenia B) Vitamin C deficiency C) Bernard-Soulier syndrome D) Hemophilia A E) von Willebrand's disease
E) von Willebrand's disease
A congenitally inherited disease in which there is a defect in collagen production is known as what?
Ehler-Danlos Syndromes
If the PT is abnormal and the aPTT is abnormal, what secondary hemostatic disorders could it be?
Extrinisic pathway disorder *Factor VII Deficiency* Coumadin
Situation: a patient has a normal bleeding time, normal PT and APTT test and a history of "delayed bleeding". 5M urea test results are abnormal. This is an indication of a deficiency of what factor?
Factor XIII
If both the PT and aPTT are normal, and a secondary hemostatic issue is expected, what could be the disorder?
Factor XIII deficiency
Glanzmann thrombasthenia is a qualitative platelet disorder involving an absence of what?
GPIIb/GPIIIa
A decrease in platelet alpha granules is known as which storage pool platelet deficiency?
Gray platelet syndrome or α-Storage Pool Disease
Name some common bleeding disorders that can be seen in normal "well" babies.
ITP Vitamin K deficiency Hemophilia
What are some names of ITP?
Idiopathic Thrombocytopenic Purpura Immune Thrombocytopenic Purpura Immune Thrombocytopenia
State the characteristics of chronic ITP.
Insidious - chronic, slow occuring
Explain the mechanism of antiphospholipid antibody (aka lupus/lupus like anticoagulant) and the expected test results.
Lupus anticoagulants (LA) or lupus-like anticoagulants (LLAC) are autoantibodies that react with the phospholipids in coagulation testing reagents - interfere with testing reagents no bleeding problems, but actually prone to clotting problems in the patient *Lab Testing* aPTT/PT: increased aPTT, sometimes PT - aPTT has more phospholipids in it than PT 1:1 Mix: not corrected (abs bind regardless) DRVVT (screen-russel venom): abnormal - should correct itself in confirmatory test
Idiopathic Thrombocytopenic Purpura (ITP) usually presents with an elevated: Platelet count MPV WBC count APTT Schistocyte count
MPV
Describe the symptoms associated with drug induced thrombocytopenia.
Many drugs implicated Symptoms - excess bleeding occurs suddenly and may be severe Example: - anti-malarial drugs - ab to the drug itself - drug binds to platelets and whole complex is removed along with the platelet by spleen
Explain the mechanism of Neonatal alloimmune thrombocytopenia (NAIT).
Maternal antibodies produced against paternal antigens on fetal platelets - Similar mechanism to HDFN - usually due to polymorphism of GPIIIa (diff forms, child inherited father's form that is diff than mothers)
State the following characteristics of Hemophilia A: Mechanism: Clinical Findings: Lab Results: Platelet count = PFA and platelet aggregation studies = Bleeding time = PT = APTT = 1:1 mix APTT =
More common than Hemophilia B *Mechanism:* Deficiency of Factor VIII *Clinical Findings:* *Lab Results:* Platelet count = normal PFA and platelet aggregation studies = normal Bleeding time = normal PT = normal APTT = prolonged 1:1 mix APTT = corrected/normal FVIII assay: abnormal FIX Assay: normal
What is the mechanism of an acquired single factor inhibitor? State the expected aPTT and 1:1 mix results.
Patient has an IgG (allo or auto) ab to a factor - hemophilias (A more common) - normal patients - pregnant women - autoimmune or lymphoid neoplasms *Lab Results* aPTT= markedly prolonged 1:1 mix: not corrected - ab will bind regardless Specific inhibitor assay (Bethesda Titer Assay)
Patients who have platelets with a storage pool defect will have abnormal: Platelet count Platelet aggregation studies PT and APTT Bleeding time Rumple-Leed (capillary fragility) test
Platelet aggregation studies
What is usually seen in the case of platelets being destroyed via immune mechanisms? Bone marrow? PBS?
Platelet destruction caused by antibodies - Platelets sensitized with antibody - Removed by macrophages of spleen/liver *Bone marrow* - usually increased megakaryocytes *Peripheral Blood:* - increased MPV; decrease in overall platelet count; platelets can be larger in size
What is the test that is most helpful in distinguishing between heparin and a circulating anticoagulant?
Reptilase Time
State the characteristics of acute ITP.
Resolves in less than 6 months
In Bernard-Soulier disease, platelet aggregation studies will show an abnormal aggregation curve with with compound?
Ristocetin (RIST)
Which laboratory test analyzes VWF qualitatively for abnormalities of the molecular structure?
Ristocetin-induced platelet aggregation (RIPA)
Name some major sources of vitamin K.
green, leafy vegetables and production by bacteria in GI tract
What is hypofibrinogenemia? How does it manifest? State the following expected results for: Bleeding Time: PT: aPTT: Thrombin Time: Retilase Time: Fibrinogen:
heterozygous form with fibrinogen levels between 20 - 100 mg/dL (normal: 200 - 400 mg/dL) - decreased fibrinogen levels *Bleeding Time:* normal *PT:* normal/abnormal *aPTT:* normal/abnormal *Thrombin Time:* abnormal *Retilase Time:* abnormal *Fibrinogen:* abnormal
What is Afibrinogenemia? How does it manifest? State the following expected results for: Bleeding Time: PT: aPTT: Thrombin Time: Retilase Time: Fibrinogen:
no detectable fibrinogen is found - Platelet aggregation abnormal *Bleeding Time:* abnormal *PT:* abnormal *aPTT:* abnormal *Thrombin Time:* abnormal *Retilase Time:* abnormal *Fibrinogen:* absent
What is the mechanism via which ITP occurs?
platelet autoabs produced by the patient - immune destruction of platelets acute - children post viral infections chronic - adults secondary, idiopathic
The production of an autoimmune IgG antibody associated with administration of heparin results in which test result to be abnormal?
platelet count (decreased)
What is Dysfibrinogenemia? What does it manifest as? State the following expected results for: Bleeding Time: PT: aPTT: Thrombin Time: Retilase Time: Fibrinogen:
structural abnormality in the fibrinogen molecule due to a mutation - Abnormal release of peptides A and B by thrombin - Abnormal polymerization - Defective cross-linking of fibrin monomers *Bleeding Time:* normal *PT:* normal/abnormal *aPTT:* normal/abnormal *Thrombin Time:* abnormal *Retilase Time:* abnormal *Fibrinogen:* normal
A decrease in platelet dense granules is known as which storage pool platelet deficiency?
δ-Storage Pool Disease
