Other Disorders

Liver Disease

 

Obstructive disease

- decreased absorption Vitamin K as it is fat soluble

- Vit K dependent factors affected

- II, VII, IX & X 

- raised INR

 

Hepatocellular Disease

- impairs synthesis of all coagulation proteins

- bleeding episodes treated with FFP or Cryoprecipitate

 

Vit K Deficiency

 

Occurs with impaired intake or malabsorption

- Inflammatory Bowel Disease

- blood contains no functional forms of II, VII, IX & X

- reversed in 1/7 of Vit K administration

 

Antiphospholipid Syndrome

 

Phospholipid antibodies

- Broad family of autoantibodies that target phospholipids

- can be either procoagulant or anticoagulant

 

Lupus anticoagulant antibodies 

- procoagulant

- associated with thromboembolic events rather than clinical bleeding

 

Antiphospholipid syndrome

 

Need 1 clinical and 1 laboratory for diagnosis

 

Clinical

- Vascular thrombosis

- Catastrophic antiphospholipid syndrome

- Complications of pregnancy (spontaneous abortions / premature intra-uterine deaths)

 

Laboratory

- detected on 2 tests 6 weeks apart

- anticardiolipin antibodies

- lupus anticoagulant antibodies

 

Prevalence

 

Antiphospholipid antibodies is 1-5% in young adults

SLE : anticardiolipin & lupus anticoagulant – 15-30%

 

Investigation

 

All patients with a first thrombotic episode should be screened for anticardiolipin & lupus anticoagulant antibodies

 

Treatment

 

Antiphospholipid antibodies

- no thrombosis

- modify 2° risk factors if have antibodies

- aspirin is not protective against thrombosis

 

Antiphospholipid syndrome

- warfarin 2-2.9 decreases thrombosis rate

 

Thrombocytopaenia

 

Definition

 

Platelet count < 50,000 x 10.6/L

 

Causes

 

1.  Defective production

- disturbane of bone marrow

- i.e. secondary to medication

 

2. Excessive destruction

 

Drug-Induced Thrombocytopaenia

- Quinine, Sulphonamides, Digoxin, Morphine & H2 antagonists

- drug binds to platelets & acts as Hapten

- form antigenic substances

- complement activation and Platelets lysis

 

HITS

- 2° AB- heparin-platelet complexes formed & cause platelet aggregation

- thrombocytopaenia from thrombosis

- rapidly reversed once heparin ceased

- should monitor platelet count in patients on heparin

 

Idiopathic Thrombocytopenic Purpura

- relatively common disorder

 

3. Excessive splenic pooling

 

4. Massive transfusion

 

Effects

 

Spontaneous bleeding if < 20,000

Post-traumatic bleed increased if < 100,000