patho

1. HEMORRHAGIC DIATHESIS I
(BLEEDING DISORDERS)
Dr. S. Vaidya,
Dept. of Pathology

2. OBJECTIVES
1. list of common basic screening tests in bleeding
disorders & its significance.
2. list of common bleeding disorders
3. aetiopathogenesis and laboratory diagnosis of
immune thrombocytopenic purpura (ITP).

3. HEMORRHAGIC DIATHESIS (BLEEDING
DISORDERS)
• are a group of disorders characterized clinically by
abnormal bleeding, which can be either spontaneous
or become evident after some inciting event
(trauma, surgery)

4. NORMAL HEMOSTASIS
• normal hemostasis is a consequence of tightly regulated
processes that maintain blood in a fluid state in normal
vessels, yet also permit the rapid formation of a
hemostatic clot at the site of a vascular injury
• normal hemostasis depends upon normal function of:
1. endothelium (blood vessel)
2. platelets
3. coagulation factors

5. SCREENING TESTS FOR HAEMOSTASIS
1. Bleeding time (BT):
• measures the time taken for a standardized skin
puncture to stop bleeding.
• normal range: 2 - 9 minutes
• prolonged BT indicates a defect in platelet numbers
or function.

6. 2. Platelet count:
• are obtained using anticoagulated blood
a. manually
b. electronic particle counter
• normal range: 150 to 450x103/µl.
• associated disorders :
a. thrombocytopenia
b. thrombocytosis

8. 3. Prothrombin time (PT):
• this assay tests the extrinsic & common coagulation
pathways.
• normal range: 10 - 14 seconds.
⮚ prolonged PT: due to deficiency or dysfunction of
factors V, VII, factor X, prothrombin (II), or fibrinogen
(I).

9. 4. Partial thromboplastin time(PTT):
• this assay tests the intrinsic and common
coagulation pathways.
• normal range: 30 - 40 seconds.
⮚ Prolonged PTT: due to deficiency or dysfunction of
factors V, VIII, IX, X, XI, or XII, prothrombin (II), or
fibrinogen (I).

10. • other specialized tests available are:
1. levels of specific clotting factors
2. fibrinogen
3. fibrin split products
4. presence of circulating anticoagulants.
5. platelet adhesion tests
6. platelet aggregation tests

11. BLEEDING DISORDERS
• the causes of bleeding disorders maybe broadly
divided into:
1. bleeding disorders due to vascular abnormalities
2. bleeding disorders due to platelet abnormalities
3. disorders of coagulation factors
4. combination of all of the above (Disseminated
Intravascular Coagulation / DIC)

12. LIST OF COMMON BLEEDING DISORDERS
1. immune thrombocytopenic purpura (ITP)
2. hemophilia A
3. hemophilia B
4. von Willebrand disease
5. disseminated intravascular coagulation (DIC)

13. IMMUNE THROMBOCYTOPENIC PURPURA
(ITP)
• immune thrombocytopenic purpura (ITP) is
characterized by immunologic destruction of
platelets and normal or increased megakaryocytes in
the bone marrow.

16. • on the basis of duration of illness, ITP is classified
into:
1. acute ITP
1. chronic ITP

17. CHRONIC ITP
• occurs more commonly in adults, particularly in
women of child-bearing age.
• age: 40,
• M:F ratio = 1:3
• it can be:
1. primary: absence of any known risk factors
2. secondary: occur in variety of predisposing
conditions and exposures

18. PATHOGENESIS
• also caused by autoantibodies to platelets.
⮚ autoantibodies, most often directed against platelet
membrane glycoproteins IIb-IIIa or Ib-IX

19. CLINICAL FEATURES
1. petechial haemorrhages
2. easy bruising
3. mucosal bleeding: menorrhagia in women, nasal
bleeding, bleeding from gum, melaena and
haematuria.
4. intracranial haemorrhage (rare)
5. hepatomegaly
6. splenomegaly (uncommon)

20. ACUTE ITP
• self-limited disorder, seen most frequently in children
following recovery from viral infection or upper
respiratory infection.
⮚ caused by antiplatelet antibodies
• onset of acute ITP is sudden & severe thrombocytopenia
but recovery occurs within a few weeks to 6 months.
⮚ in about 20% of children have a childhood form of
chronic ITP that follows a course similar to the adult
disease.

21. LABORATORY FINDINGS
1. platelet count: markedly reduced.
2. blood film: shows occasional platelets.
3. bone marrow: shows increased number of
megakaryocytes.
4. anti-platelet IgG antibody: can be demostrated in
the serum of patients.
5. platelet survival studies: markedly reduced platelet
lifespan (normal 7-10 days).

22. TREATMENT
• spontaneous recovery in 90% cases of acute ITP.
• corticosteroid therapy
• splenectomy:
⮚ thrombocytopenia is improved by splenectomy,
indicating that the spleen is the major site of
removal of platelets.

23. THANK YOU