Coagulation Defects

Question 1

Ix for Haemophilia (7)

Answer 1

FBC, blood film, platelets

U+Es

LFTs to rule out hepatic cause

coagulation screen

BM biopsy

APTT-intrinsic and common pathway-prolonged

PT-normal

Question 2

Features of haemophilia A (2)

Answer 2

Factor VIII deficiency

5 times more common than haemophilia B

Question 3

Presentation of haemophilia A (6)

Answer 3

most present in 1st yr when stalking to walk/crawl/fall

neonatal bleeding after circumcision/operative procedures

neonatal intracranial haemorrhage

bleeding into joints w/o trauma

GI bleeding: haematemesis, melaena, frank PR bleed

haematuria

Question 4

Features of haemophilia B (2)

Answer 4

factor IX deficiency

less common

Question 5

Haemophilia prophylactic Mx

Answer 5

weekly factor VIII transfusion

Question 6

Mx of acute bleeding episode in haemophilia (4)

Answer 6

IV recombinant factor VIII/IX concentrate

in minor bleeds, can increase levels 30% above normal

in major bleeds/surgery, need to increase lvls 100% above normal

give SC vit K to prevent haematomas as in haemorrhagic disease of the newborn

(avoid IM injections, NSAIDs and aspirin)

Question 7

Genetics and pathology of Von Willerbrand’s Disease (2)

Answer 7

most are AD, complete vWD is AR

vWF brings platelets close to epithelium>platelets bind together>binds and protects factor XIII

(>22 types of vWD)

Question 8

Presentation of vWD (5)

Answer 8

bruising

epistaxis

menorrhagia

bleeding post-tooth extraction

make sure no intraventricular haemorrhage

Question 9

Ix for vWD (3)

Answer 9

Dx:

• raised APTT
• low factor VIII

also has prolonged bleeding time unlike haemophilia

Question 10

Mx of vWD (2)

Answer 10

desmopressin>release of vWF and factor VIII

in acute bleeds: recombinant vWF

Question 11

Acquired coagulation defects (2)

Answer 11

Vit K deficiency:

• haemorrhagic disease of newborn-give SC vit K
• liver disease
• malabsorption

Drugs:

• warfarin
• heparin