APPROACH TO
COAGULATION DISORDERS
Dr.K.Pavithran, MD, DM
Assistant Professor,Dept of Hematology
Medical College Hospital
Trivandrum-695011, India

Clinical approach
1.
2.
3.
4.

Is the bleeding significant ?
Local Vs Systemic ?
Platelet Vs Coagulation disorder ?
Inherited Vs Acquired ?

Laboratory Approach
1.
2.
3.
4.
5.

Demonstration of the defect
Identification of the defect(s)
Assessment of severity
Consequential studies eg. carrier detection
Monitoring of treatment

Screening Tests
1. Platelet count & morphology
2. Bleeding Time
3. Clotting Time
4. Prothrombin Time
5. Activated Partial Thromboplastin Time
6. Thrombin Time

Collection of blood sample
1. Minimum circulatory stasis
2. Clean venous puncture
3. Proper anticoagulant
4. Proportion of blood to anticoagulant
5. Separation of plasma and storage
6. Effect of stress, pregnancy, drugs
7. Effect of PCV on the proportion of plasma to anticoagulant

Prolonged PT/APTT
•
•
•
•

Coagulation factor deficiency/inhibitor
Test plus control plasma - 1:1
Repeat PT/APTT
> 50% correction
– Yes - Factor deficiency
– No - inhibitor timed incubation abnormally increasing specific inhibitor

no change
Lupus Anticoagulant

HMWK

VII

XII
PK
XI
APTT
IX

PT

VIII

X

PT - 
APTT, TT, PLC - N

* Factor VII deficiency
* Anticoagulant therapy

V
II
I

TT

HMWK

VII

XII
PK
XI
APTT
IX

PT

VIII

X

APTT - 
PT, TT, PLC - N

* Factor deficiency
* vWD
* Inhibitors
* Heparin therapy

V
II
I

TT

Mixing tests with APTT
APTT of test plasma +
Aged plasma
Adsorbed plasma
Diagnosis
No correction

Corrected

VIII

Corrected

No correction

IX

Corrected

Corrected

XI,XII

Prolonged APTT, BT von Willebrand’s disease
Ristocetin Induced Platelet Agglutination
VIII:C
vWF:Ag vWF multimeric analysis
Type 1 - Partial deficiency of vWF
2A - Absence of large and interm. multimers
2B - Absence of large multimers
2M- multimers normal, pl. function 
2N -  affinity for FVIII
3 - severe deficiency of vWF

HMWK

VII

XII
PK
XI
APTT
IX

PT

VIII

X

PT, APTT - 
TT, PLC - N

*
*
*
*

V
II
I TT

Common Pathway Factor deficiency
Vitamin K deficiency
Oral anticoagulant therapy
Liver disease

Mixing tests with PT
PT of test plasma +
Aged plasma

adsorbed plasma

Diagnosis

Corrected

Not corrected

X

Not corrected

Corrected

V

Not corrected

Partial

II

HMWK

VII

XII
PK
XI
APTT
IX

PT

VIII

X

PT, APTT, TT - 
PLC - N

* Hypo / dysfibrinogenemia
* Heparin
* Liver disease
* Systemic hyperfibrinolysis

V
II
I

TT

HMWK

VII

XII
PK
XI
APTT
IX

PT

VIII

X