Acquired coagulation disorders - PowerPoint Presentation

Slide1

Acquired coagulation disordersSlide2

Acquired coagulation disorders:

They are

more common

than the inherited disorders. Unlike the inherited disorders,

multiple clotting

factor deficiencies are usual.Slide3

The acquired coagulation disorders.

Deficiency of vitamin K-dependant factors

Haemorrhagic

disease of the newborn

Biliary

obstruction

Malabsorption

of vitamin K(e.g. tropical

sprue

, gluten induced

enteropathy

)

Vitamin K-antagonist therapy (e.g.

coumarins

,

indandiones

)

Liver disease

Disseminated intravascular coagulation

Inhibition of

coagtulation

Specific inhibitors (e.g. antibodies against factor VIII)

Non-specific inhibitors (e.g. antibodies found in systemic lupus

erythematosus

, rheumatoid arthritis)

Miscellalleous

Diseases with M-protein production

L-

Asparaginase

Therapy with heparin,

defibrinating

agents or

thrombolytics

Massive transfusion syndromeSlide4

Vitamin K deficiency in children or adults

Caused by :

obstructive jaundice

pancreatic

small bowel disease

inadequate diet

malabsorption

drugs as

warfarin

which act as

vit.K

antagonists is

associated with

decrease in functional activity

of factors : II, VII,IX, X & protein C & S ,

but the

immunological methods show normal

levels of these factors.Slide5

Haemorrhagic

disease of the newborn

Vitamin K-dependent factors are low at birth and fall further in breast-fed infants in the first few days of life.

Liver cell immaturity,

lack of gut bacterial synthesis of the vitamin and low quantities in breast milk may all contribute to a deficiency which may cause

haemorrhage

, usually on the second to fourth

day of life, but occasionally during the first 2 monthsSlide6

liver disease

Multiple haemostatic abnormalities contribute to a bleeding tendency and may exacerbate

haemorrhage

from

oesophageal

varices

,

1

Biliary

obstruction

results in impaired absorption of vitamin K and therefore decreased synthesis of factors II, VII, IX and X.

2 With severe

hepatocellular

disease

, in addition to a deficiency of these factors, there are often reduced levels of factor V and fibrinogen and increased amounts of

plasminogen

activatorSlide7

3 Functional abnormality of fibrinogen

(

dysfibrinogenaemia

)

4 Decreased

thrombopoietin

production from

the liver contributes to thrombocytopenia.

5

Hypersplenism

associated with portal hypertension frequently results in thrombocytopenia.

6 Disseminated intravascular coagulationSlide8

Haemostasis

tests in Acquired coagulation disorders Slide9

DIC (disseminated intravascular coagulation).

Wide spread intravascular deposition of fibrin with consumption of coagulation factors & platelets occur as consequence of many disorders which release

procoagulant material

into the circulation or cause wide spread

endothelial damage

or platelets aggregation.

It may be associated with fulminant hemorrhagic syndrome or run less severe & more chronic course.Slide10

Coagulation deficiency caused by antibodies

Circulating antibodies to coagulation factors are occasionally seen with an incidence of approximately1 per

millon

per year.

Alloantibodies

to factor VIII

occur in 5-10% of

haemophiliacs

.

Factor

VIII

autoantibodies

may also result in a bleeding syndrome.

These immunoglobulin G (

IgG

) antibodies occur rarely post-partum, in certain

immunolological

disorders (e.g. rheumatoid arthritis), in cancer and in old age.

Treatment usually consists of a combination of

immunosuppression

and treatment with factor replacementSlide11

Massive transfusion syndrome

Many factors may contribute to a bleeding disorder following massive transfusion, Blood loss results in

reduced levels of platelets,

coagulation

factors and inhibitors,

Further dilution of these factors occurs

during replacement with red cells,