Bleeding disorders

Question 1

vascular abnormalities

Answer 1

hereditary - marfans

acquired - vasculitis e.g. HSP [kids]

Question 2

thrombocytopenia

Answer 2

hereditary

acquired - reduced production which is a marrow problem or increased destruction

Question 3

causes of peripheral platelets destruction

Answer 3

coagulopathy - DIC
AI - immune thrombocytopenia purpura (ITP) - most common cause
hypersplenism

Question 4

platelet functional defects

Answer 4

hereditary

acquired - drugs (NSAIDs, aspirin), renal failure

Question 5

VW deficiency

Answer 5

acquired

hereditary - AD, common, variable severity but generally mild

Question 6

what is the most commonest cause of primary haemostatic failure and what are the causes of this

Answer 6

thrombocytopenia - usually acquired

causes - marrow failure, peripheral destruction

Question 7

failure of fibrin clot formation causes

Answer 7

multiple clotting factor deficiencies - acquired, DIC

single clotting factor deficiency - hereditary, haemophilia

Question 8

multiple factor deficiencies

what do ix show

Answer 8

liver failure
vit K defic/warfarin therapy
complex coagulopathy - DIC

prolonged PT and prolonged APTT

Question 9

why does liver failure cause multiple clotting factor deficiencies

Answer 9

all coag factors are synthesised in hepatocytes - reduced in liver failure

Question 10

why does a lack of vit K lead to multiple clotting factor deficiencies

Answer 10

factors II, VII, IX and X are carboxylated by vitamin K which is essential for function

Question 11

sources of vit K
where is it absorbed
what is required or its absorption

Answer 11

diet, intestinal synthesis

absorbed in the upper intestine

requires bile salts for absorption

Question 12

causes of vit K deficiency

Answer 12

poor dietary intake 
malabsorption 
obstructive jaundice 
Vit K antagonists such s warfarin 
haemorrhagic disease of the newborn

Question 13

what is DIC
what does it lead to
what does it present like

Answer 13

excessive and inappropriate activation of the haemostatic system - primary, secondary and fibrinolysis

microvascular thrombus formation - end organ failure

clotting factor consumption - bruising, purpura and generalised bleeding

Question 14

causes of DIC

Answer 14

sepsis
obstetric emergencies
malignancy
hypovalaemic shock

Question 15

treatment of DIC

Answer 15

treat the underlying cause

replacement therapy - platelet transfusion, plasma transfusions, fibrinogen replacement

Question 16

what is haemophilia

Answer 16

an X linked hereditary disorder in which abnormally prolonged bleeding recurs episodically at one or a few sites on each occasion
no abnormality of primary haemostasis

Question 17

Haemophilia A
Haemophilia B
which is more common

Answer 17

A - factor 8 defic
B - factor 9 defic

A is five times more common as B

Question 18

where is the bleeding from in haemophilia

severity depends on what

Answer 18

medium to large blood vessels

mild, mod and severe affected families depending on factor 8/9 levels

Question 19

clinical features of severe haemophilia

Answer 19

recurrent haemasrthroses
recurrent soft tissue bleeds - bruising in toddlers
prolonged bleeding after dental extractions, surgery and invasive

Question 20

ix of DIC show what

Answer 20

prolonged PT and ATTP
low platelet count
increased d dimers

Question 21

ix of haemophilia show what

Answer 21

normal PT time

isolated prolonged APTT