Bleeding And Thrombosis 10/6 Flashcards
What is the term for bleeding into joints?
What usually causes it?
Hemarthrosis
Usually caused by coagulation factor deficiency.
What do injured BVs release that attracts platelets?
ADP
What Coag test asses the extrinsic pathway?
PT: prothrombin time
Measures time to form fibrin clot. Normal: 10-12 s
Monitored in pt’s on warfarin
What Coag test asses the intrinsic pathway?
PTT: partial thromboplastin time
Uses neg charged particles, calcium; time to form fibrin clot.
Used to measure response to HEPARIN
What is the cause if ONLY the PT is prolonged?
Defect in factor 7
What is the differential (3) if patient presents with petechia and purpura but the PT and PTT are both normal?
Vessel wall abnormalities:
- Scurvy
- Infection
- Drugs
What is the cause if ONLY the PTT is prolonged?
Defects of factors 12, 11, 9, 8
How do you test whether or not there is a clotting factor deficiency?
Mixing study.
Patient’s plasma mixed with normal plasma.
Clotting factor deficiency: correction after mix
Inhibitor: no correction after mix
How are hemophilia A and B genetically inherited?
X-linked recessive.
Only males.
Symptoms of hemophilia: (4)
- Spontaneous/traumatic subcutaneous bleeding
- Blood in urine
- Bleeding in mouth, lips, tongue
- Bleeding into joints, cns, GI tract
What will Coag test findings indicate with Von willebrand’s disease?
Prolonged PTT
VWF stabilizes factor 8.
defect w/ factor 8 - long PTT
What are the quantitative values for thrombocytopenia and thrombocytosis?
Thrombocytopenia: <100k
Thrombocytosis: >400k
Hallmarks of thrombocytopenia (3)
Immediate post-surgical bleeding, petechia, ecchymosis, menorrhagia
Reddish-purple blotchy rash
Spontaneous bleeding from minor trauma
Causes of thrombocytopenia? (3)
- Decreased production from bone marrow (toxins, radiation, infx, leukemia)
- Increased destruction (autoimmune)
- Increased platelet consumption (DIC)
- Spleen sequestration
- Spurious- clumping of platelets. BAD!!
What demographic usually presents with thrombotic thrombocytopenia purpura (ttp)
Adults, 30’s, mostly women, after virus.
What is the Pentad (5) symptoms of TTP?
- Fever
- Thrombocytopenia w/ purpura
- MHA (micro angiopathic hemolytic anemia)
- Neurological deficit
- Renal failure
What enzyme is deficient in TTP?
ADAMST-13
Can’t degrade multimeters of VWF
What is the treatment for TTP?
Therapeutic plasma exchange with FFP: removed multimers and adds VWF
What will peripheral blood smear for MHA show?
Schistocytes
Large platelets
What demographic most commonly gets HUS (hemolytic uremic syndrome)?
Children 1-4 y.o
Presents with bloody diarrhea
What is the triad of symptoms for HUS?
- Thrombocytopenia
- MHA
- Renal dysfunction (hematuria, proteinuria, uremia)
What demographic most commonly presents with ITO (immune thrombocytopenic purpura)?
Young women
What causes ITP?
Autoantibody mediated destruction of platelets. Platelets are opsonized and removed by spleen.
What are the four symptoms of ITP?
Petechia
Menorrhagia
Hematuria
Melena
What is a defect of platelet adhesion?
Bernard-Soulier
What is defective formation of platelet aggregation?
Glanzman thrombasthenia
Disseminated intravascular coagulopathy (DIC) is a thrombohemorrhagic disorder with: (3)
- Excessive coagulation activation
- Consumption of platelets, fibrin, and coagulation factors: hemorrhage
- Activation of fibrinolysis: formation of thrombi in microvasculature
5 diagnostic findings of DIC:
- Thrombocytopenia
- MHA - schistocytes
- Prolonged pt/PTT
- Increased fibrin split products (fsp) & d-dimers
- Decreased fibrinogen and coagulation favored (5 & 8)
What 2 enzymes promote plasminogen conversion to plasmin?
T-PA
UPA
What enzyme inhibits plasminogen conversion to plasmin?
PAI-1
Released from endothelial cells
**PAI-1 deficiency can cause thrombus formation
What inactivates plasmin?
Alpha 2-antiplasmin
What 2 coagulation factors does protein c inhibit to inhibit thrombin’s ability to activate CF’s and platelets?
5 & 8
What Coag cofactors are vitamin k dependent?
2, 7, 9, 10
Protein c and s
What are the 2 genetic causes of hypercoagulable states?
- Factor 5 Leiden point mutation (reduced activity of pC)
- Mutant form of factor 5 (insensitive to pC)
- Prothrombin gene point mutation (elevated prothrombin)
What are the 4 acquired causes of hypercoagulable states?
- BC
- Cancer
- HIT (heparin induced thrombocytopenia)
- Anti phospholipid syndrome
What is a likely outcome of protein C or S deficiency?
Deep vein thrombosis
What is the syndrome of thrombosis associated with a visceral malignancy, such as adenocarcinoma of the pancreas?
Trousseau’s syndrome
