Idiopathic Thrombocytopenic Purpura

1. Idiopathic Thrombocytopenic
Purpura (ITP)
Jayatheeswaran. Vijayakumar
Жаятесваран вижаякумар
Group: 88

2. Background
 ITP is also know as:
 Primary Immune Thrombocytopenic Purpura
 Autoimmune Thrombocytopenic Purpura
 It is defined as an isolated thrombocytopenia with normal bone marrow in the
absence of other causes of thrombocytopenia.
 ITP has 2 distinct clinical syndromes, manifesting as an acute condition in children
and a chronic condition in adults.

3. Background
 Acute ITP often follows an acute infection and has a spontaneous resolution within
2 months. Chronic ITP however, persist longer than 6 months without a specific
cause.
 It is important to note that ITP is a diagnosis of exclusion.

4. Pathophysiology
 ITP is a disease of increased peripheral platelet destruction, with most patients
having autoantibodies against platelet membrane glycoproteins IIb-IIIa and Ib-IX.
 In approximately 60% of cases autoantibodies against platelets can be detected.
They are typically of the IgG type.
 IgG autoantibodies are also thought to damage megakaryocytes. As such, relative
marrow failure may contribute to this condition, since most patients have either a
normal or diminished platelet production.

5. Pathophysiology
 Abnormal T-cell activity is thought to be the stimulus for autoantibody production
in ITP.
 Impaired production of the glycoprotein hormone thrombopoietin which is a
stimulant for platelet production may be a contributing factor to the reduction in
circulating platelets.

6. Epidemiology
 In the United States:
 The Incidence of ITP in adults is approximately 66 cases per 1,000,000 per year.
 An average estimate of incidence in children is 50 cases per 1,000,000 per year.
 New cases of chronic refractory ITP comprise approximately 10 cases per 1,000,000 per year.
 Hemorrhage represents the most serious complication; intracranial hemorrhage is the
most significant. The mortality rate from hemorrhage is approximately 1% in children
and 5% in adults.
 Spontaneous remission occurs in more than 80% of cases in children. However, it is
uncommon in adults.

7. Epidemiology
 In the United States:
 Peak prevalence occurs in adults aged 20-50 years.
 Peak prevalence occurs in children aged 2-4 years.
 Approximately 40% of all patients are younger than 10 years.
 In Chronic ITP (adults), the F:M ratio is 2.6:1. More than 72% of patients older than
10 years are female.
 In Acute ITP (children), distribution is approximately equal between males (52%)
and females (48%).

8. Bleeding
occurs if the platelet count is below 20,000 per μl.

9. Presentation
 Purpura
 Hemorrhagic Bullae (on
mucous membranes)
 Intracranial Hemorrhage
(with possible neurological
symptoms)
 Non-Palpable Petechiae
(mostly occur in dependent
regions)

10. Presentation
 Epistaxis
 Gingival Bleeding
 Signs of GI bleeding
 Retinal Hemorrhage
 Menometrorrhagia/ Menorrhagia
 Spontaneous Bleeding (when
platelet count is less than
20,000/mm 3.)

11. Presentation
 Non-Palpable Spleen
 The prevalence of palpable spleen in patients with ITP is approximately the same as that
in the non-ITP population (i.e. 3% in adults, 12% in children.)
 Despite the destruction of platelets by splenic macrophages, the spleen is normally not
enlarged. In fact, an enlarged spleen should lead to a search for other possible causes
for the thrombocytopenia.

12. Diagnosis
 As ITP is a diagnosis of exclusion it is important that a complete and through patient
history be taken.
 It is important to focus on the symptoms of bleeding (e.g. type, duration & severity) and
on symptoms that may exclude other causes of thrombocytopenia such as liver disease,
thrombosis, autoimmune disease (e.g. nephritis, cutaneous vasculitis & arthritis), and
infection (particularly HIV.)
 It is also important to elicit risk factors of HIV, and systemic symptoms linked to other
illnesses or to medications (e.g. heparin, alcohol, quinidine/quinine or sulfonamides)
that may cause thrombocytopenia. Medications can be a common etiology for inducing
thrombocytopenia, and patients should have their medications carefully reviewed. In
children specifically, recent live virus immunization should also be considered (MMR, Flu
& Chickenpox vaccines.)

13. Diagnosis
 Bone marrow examination may be performed on patients over the age of 60 and those
who do not respond to treatment, or when the diagnosis is in doubt. On examination of
the marrow, an increase in the production of megakaryocytes may be observed and
may help in establishing a diagnosis of ITP.
 An analysis for anti-platelet antibodies is a matter of clinician's preference, as there is
disagreement on whether the 80% specificity (true positive rate) of this test is sufficient
to be clinically useful.
 In order to make an accurate diagnosis, the clinician should be able to differentiate
between the many hematological diseases that share a similar clinical picture to ITP but
have very different modes of therapy.

14. ITP vs. TTP vs. DIC
Parameters ITP TTP DIC
Pathogenesis Antiplatelet Antibodies Endothelial Defect Thrombin Excess
Clinical Condition Not Sick Sick Sick
Red Cells N Schistocytes Schistocytes +/-
PT/INR N N/Slightly Increased Increased
PTT N N/Slightly Increased Increased
Fibrinogen N N Decreased
Fibrin Monomers N Slightly Increased Increased
Fibrin Degradation N Slightly Increased Increased
D-dimer N Slightly Increased Increased
Therapy Steroids, IVIg & Splenectomy Plasma Exchange & Vincristine
(mitosis inhibitor)
Plasma/Platelet Transfusion &
ATIII?

15. Workup
 Complete Blood Count (CBC):
 Isolated thrombocytopenia (key laboratory finding).
 The white blood cell (WBC) count should be normal.
 Hemoglobin level should be normal, unless severe hemorrhage has occurred.
 Peripheral Smear:
 If truly giant platelets are found this is indicative of congenital thrombocytopenia.
 Coagulation Studies:
 Results typically appear normal and a normal bleeding time does not exclude a platelet
disorder. (e.g. vWD type 2)

16. Workup
 Imaging Studies:
 A CT scan of the head is warranted if concern exists regarding intracranial hemorrhage.

17. Treatment
 Treatment of children is usually
supportive because most children
spontaneously recover.
 Even after months or years of
thrombocytopenia, most children
have spontaneous remissions.
 If mucosal bleeding occurs,
corticosteroids or IVIG may be given.

18. Treatment
 Corticosteroids & IVIg:
 Prednisone (Deltasone, Orasone, Sterapred)
 Methylprednisolone (Solu-Medrol, Depo-Medrol)
 Intravenous immune globulin (IVIg)
 Treatment is based on the patient's clinical condition, the absolute platelet count, and
the degree of symptoms.
 In children with ITP who have no bleeding or mild bleeding (e.g. cutaneous
manifestations such as bruising and petechiae), the American College of Hematology
(ACH) recommends management with observation alone, regardless of the platelet
count.

19. Treatment
 TPO Receptor Agonist:
 Eltrombopag (25 to 75 mg po once/day)
 Romiplostim (1 to 10 mcg/kg sc once/week)
 Available to patients with Chronic ITP who have failed other therapies.
 TPO Receptor Agonists have response rates of > 85%. However, thrombopoietin receptor
agonists need to be administered continuously to maintain the platelet count >50,000/μL.
 While they show promise for raising platelet counts, there are potential safety concerns such as
thrombocytosis and rebound thrombocytopenia.

20. Treatment
 Splenectomy:
 Splenectomy can achieve a complete remission in about two thirds of patients who relapse
after initial corticosteroid therapy, but it is usually reserved for patients with severe
thrombocytopenia, bleeding, or both.
 Splenectomy may not be appropriate for patients with mild disease. If thrombocytopenia can
be controlled with medical therapies, splenectomy is often deferred for 6 to 12 months to
allow for the chance of spontaneous remission. Splenectomy is rarely done in children.
However, if thrombocytopenia is severe and symptomatic for > 6 mo, then splenectomy is a
consideration.
 Splenectomy results in an increased risk of thrombosis and infection (particularly with
encapsulated bacteria such as pneumococcus); patients require vaccination against
Streptococcus pneumoniae, Haemophilus influenzae, and Neisseria meningitidis (ideally > 2
weeks before the procedure).

21. Treatment
 Rituximab (Mabthera, Rituxan)
 Rituximab has a response rate of 57%, but only 21% of adult patients remain in remission
after 5 yr.
 Newer studies on rituximab suggest that this agent is an effective treatment option in
splenectomized refractory or relapsed ITP patients
 More intensive immunosuppression may be required with drugs such as
cyclophosphamide and azathioprine in patients unresponsive to other drugs who
have severe, symptomatic thrombocytopenia.
 Platelet transfusion is given only for life-threatening bleeding.

22. Key Points
 The immune system destroys platelets in the circulation and at the same time
attacks bone marrow megakaryocytes, thereby reducing platelet production.
 Other causes of isolated thrombocytopenia (e.g. drugs, alcohol, lymphoproliferative
disorders, autoimmune diseases & viral infections) need to be excluded.
 Children usually have spontaneous remission; in adults, spontaneous remission
may occur during the first year but is uncommon thereafter.

23. Key Points
 Corticosteroids (and sometimes IVIg or IV anti-D immune globulin) are first-line
treatments for bleeding or severe thrombocytopenia.
 Splenectomy is often effective but is reserved for patients in whom medical therapy
is ineffective or those whose disease persists after 12 months.
 Platelet transfusion is given only for life-threatening bleeding.

24. Thank You