Heritable bleeding disorders

Question 1

history of a patient with thrombosis / abnormal bleeding/ bruising

Answer 1

• date of onset
• previous history of bleeding and clinical pattern
• for young: bleeding from umbilical stump, vaccinations, circumcision
• drug and family history

Question 2

tests in coagulation screen

Answer 2

all tests are Ca dependent so Ca added to test tube to stop blood clotting. sample then centrifuged.
- Activated Partial Prothrombin Time mix with 50:50 patient to normal plasma
- Prothrombin time: add TF substitute and Ca then time how long it takes for clot to form
Thrombin clotting time.
values can vary from one lab to another

Question 3

Haemophilia: X linked recessive disorder

Answer 3

A- Factor 8 deficiency 1 in 5,000 males
B- Factor 9 deficiency 1 in 30,000 males
Types of bleed: spontaneous/post traumatic, haem arthrosis, muscle haemorrhage, soft tissue into mouth.
Treatment: replacement of missing clotting protein/ on demand prophylaxis, factor conventrates. icing, immobilisation, rest.
Hep C vaccinations as plasma derived products can pass it on.

Question 4

Von Willebrand disease

Answer 4

most common type of bleeding disorder: both genders. associated with defective primary haemostasis.
musculotaneous bleeding and menorrhagia, post operative bleeding also common.
blood group O has lower levels of vWF
type 1: most common, just reduction, normal structure. least severe
type 2: low molecular weigh polymer, less high molecular weight VWF.
type 3: absent molecule VWF, most severe. autosomal domiant. variable penetrance.

Question 5

treatment of VWF

Answer 5

Antifibrinolytics: tranexamic acid good for minor bleeds and helping periods. vaccine aginst hep due to pooled plasma. combined pill for menorrhagia.