Dikshi jindal BDS student

1. Made
By:
TOPIC:

2. THROMOCYTOPENIAS:
•Thrombocytopenia is defined as a reduction in the
peripheral blood platelet count below the lower limit
of normal i.e. below 150,000/µl.
•Associated with abnormal bleeding that includes
spontaneous skin purpura and mucosal
heamorrhages.
•
1. Impaired platelet function
2. Accelerated platelet destruction
3. Splenic sequestration
4.Dilution loss
Drug-induced thrombocytopenia
Heparin-induced thrombocytopenia
Immune thrombocytopenic purpura{ITP}
Thrombotic thrombocytopenic purpura {TTP}

3. IMMUNE THROMBOCYTOPENIC
PURPURA {ITP}:
 Also known as idiopathic
thrombocytopenic purpura
 Characterised by: immunologic
destruction of platelets and normal or
increased megakaroycytes in the bone
marrow.

4.  Self-limited disorder seen in
children recovering from a
viral illness(e.g. hepatitis C,
AIDS, infectious
mononucleosis)or upper
respiratory illness.
 Onset of acute ITP is sudden
but recovery occurs from few
weeks to 6 months.
 Mechanism of acute ITP:
 by formation of immune
complexes containing viral
antigens
 by formation of antibodies
against viral antigens
 which cross react with
platelets and lead to their
immunologic destruction

 Occurs more commonly in
adults, particularly women of
child bearing age(20-40yrs).
 Chronic ITP is idiopathic ,
similar immunologic
thrombocytopenia may be
seen in association with SLE,
AIDS, and autoimmune
thyroiditis.
 Pathogenesis occur by:
 Formation of antiplatelet
autoantibodies, usually by
platelet associated IgG
humoral antibodies
synthesized mainly in spleen.
 These antibodies are directed
against target antigens on the
platelet glycoproteins, Gp IIb-
IIIa and Gp Ib-IX complex.

5. CLINICAL
FEATURES:
 Mostly they remain insidious as in chronic
ITP, but may appear abruptly in case of acute
ITP.
 Usual Manifestations are:
 Petechial haemorrhages
 Easy bruising, menorrhagia in women
 Bleeding from gums
 Nasal bleeding
 Splenomegaly and hepatomegaly may occur
in cases with chronic ITP
 Lymphadenopathy is quite uncommon in
either type of ITP
 Intracranial heamorrhage is however rare.

6. LAB FINDINGS:
 Platelet count: markedly reduced(10,000-
50,000/µl)
 Blood film: occasional platelets which are
larger in size
 Bone marrow: increased no. of
megakaryocytes
 With sensitive techniques, antiplatelet IgG
antibodies can be demonstrated on platelet
surface or in the serum of patients.
 Platelet survival studies revel markedly
reduced platelet lifespan, sometimes less
than 1hour, as compared with normal life
span of 7-10 days.

7. TREATMENT:
 By corticosteriod therapy
 Immunosuppresive drugs e.g.
Vincristine,cyclophosphamide
 Splenectomy
 Platelet transfusions are helpful
inpatients with severe haemorrhage.