Thrombotic Thrombocytopenic Purpura Flashcards
(30 cards)
What is TTP?
thrombotic microangiopathy caused by a deficiency of ADAMTS13, leading to widespread microvascular thrombosis.
There will be schistocytes and thrombocytopenia.
How does TPP affect INR and APTT?
No effect as it does not directly impact coagulation cascade
What is the clinical presentation of TTP?
ADAMS13 is important for cleaving vWF to regulate platelet clotting. Deficiency of this results in excessive micro vascular thrombosis causing:
*neurological symptoms (e.g., confusion, seizures)
*Fever
*Microangiopathic anaemia
*Low haemoglobin
*renal dysfunction with raised creatinine
What is immune thrombocytopenic purpura?
It is a type II hypersensitivity reaction mediated by IgG against the glycoprotein IIb/IIIa or Ib-V-IX complex on platelets.
What causes muscle haematoma and haemarthroses?
Haemophilia
What does LMWH increase the risk of?
Heparin induced thrombocytopenia whic can cause new DVT to form
How does ITP present in children?
Self-limiting disease which occurs following a viral infection
How does ITP present?
*Excessive bruising
*Prolonged bleeding
*Unusually heavy menstrual flow
*Spontaneous gum bleeding or epistaxis
How is ITP manamgned?
Watch and wait due to high rate of spontaneous remission
For persistent cases, steroids can be used as an immunosuppressant for 4-7 days
In severe cases steroids
What is used for major blood loss?
Tranexamic acid, antifibrinolytic which impair fibrinolytic dissolution
Blood transfusions
What causes high INR?
Liver failure and decrease in consumption of foods containing vitamin K
Overdose of anticoagulant
Herbal products
Which medications can cause high INR?
Antibiotic
Antigunfl
Amiodarone
What to do for patients on anticoagulants with minor bleeding?
Stop anticoagulants
Administer IV vitamin K
Repeat INR after 24 hours, may need further vitamin K
What to do for patients on anticoagulants with major bleeding?
Stop anticoagulants
Administer IV vitamin K
Administer prothrombin complex (preferred to FFP)
What is given generally for major bleeding?
Prothrombin complex concentrate
What is given as an alternative for prothrombin complex concentrate?
Fresh frozen plasma
What is the target INR for patients on anticoagulation therapy?
2.5 to 3.5
What are the blood count features of ITP?
Thrombocytopenia but with normal INR and APTT.
What are the blood count features of TTP?
Thrombocytopenia with normal PT and PTT. There will be schistosities.
LDH will be raised and haptoglobbin is low
How are bilirubin levels affected in ITP?
Normal
How are bilirubin levels affected in TTP?
High due to microangiopathic haemolytic anaemia from microthrombi occluding vessels
Why is haptoglobin low in TTP?
Consumption because of haemolytic anaemia
What is the treatment of ITP?
Watchful waiting mainly
If necessary steroids
In more extreme cases, rituximab can be considered or splenectomy
What is the treatment of TTP?
Plasmapheresis with fresh frozen plasma and cryosupernatant.
Crysupernatant lacks any vWF.
