Goal of the treatment
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Transcript Goal of the treatment
Salwa Hindawi
Salwa Hindawi
MSc, MRCPath, CTM RCPE
Director of Blood Transfusion Services
King Abdulaziz University Hospital
Jeddah, Saudi Arabia
Salwa Hindawi
PLATELETS
Produced from megakaryocytes in the bone marrow
Mean survival: 8-10 days
Removed from circulation by cells of the monocyte-
macrophage system
1/3 of the total platelet mass is found in the spleen
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Electron Micrscopy of Platelet
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DEFINITION
<150,000 platelets/microliter (nml 150,000-400,000)
2.5 % of the nml population have this
If platelet count >20,000, usually no serious
spontaneous bleeding
If less than <10,000, risk of bleeding increases and may
necessitate transfusion
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MECHANISMS OF
THROMBOCYTOPENIA
Decreased platelet production
Increased platelet destruction
Dilutional/distributional
Pseudothrombocytopenia
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MEDICATIONS
Quinidine
Amphotericin
Quinine
Vancomycin
Rifampin
Amiodarone
Bactrim
Piperacillin
Methyldopa
Sulfasalazine
Acetaminophen
Ethambutol
Digoxin
Lithium
Diclofenac
heparin
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MEDICATIONS
Methicillin
Haldol
INH
Tamoxifen
Minoxidil
Diazepam
Nitroglycerine
Gold
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ITP
Autoimmune etiology (IgG antibody to platelets)
Etiology
30% drug related
30% underlying disease (connective tissue disorders,
lymphoma, CLL)
30% idiopathic
10% viruses (HIV)
Platelets are hyperfunctional (spontaneous
bleeding is rare)
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Idiopathic Thrombocytopenic Purpura (ITP)
Autoimmune disease of children and adults
Sustained Low platelet count
No other causes )exclusion)
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Pathophysiology
Immune Mediated Mechanism
increase HLA-DR expression defects in cellular and
humoral immunity specific autoantibody production
to GpIIb/IIIa and Gp16-IX Antigens
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Pathophysiology
Platelet destruction
+
by
platelet
acrophages
Auto Ab
RES
Low
platelet
count
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bleeding
through mucus
membranes
Clinical Features of ITP in Children and Adults
Feature
Children
Adults
2-4
Equal
15-40
2:6:1
Occurrence
Peak age (yr)
Sex (F:M)
Presentation
Onset
Acute (most with symptoms < 1 week)
Symptoms
Purpura (<10% with severe bleeding)
Platelet count
Most <20 x 109/L
Course
Spontaneous remission
83%
Chronic disease
24%
Response to splenectomy
71%
Eventual complete recovery
89%
Morbidity and mortality
Cerebral hemorrhage
<1%
Hemorrhagic death
<1%
Mortality of chronic refractory 2%
disease
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Insidious (most with symptoms
<2 months)
Purpura (typically bleeding not
severe)
Most <20 x 109/L
2%
43%
66%
64%
3%
4%
5%
APPROACH TO DIAGNOSIS
HISTORY AND PHYSICAL EXAMINAION
Recent viral history
Diagnosed hematological disease
Family history
Recent live virus vaccination (measles)
Poor nutritional states
Medications
Pregnancy
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Diagnosis
Diagnosis by Exclusion
1 – Clinical finding
Bleeding and /or purpura
Isolated thrombocytopenia
No evidence of other disease
2 – peripheral blood smear
3 – platelet antibody test
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4-Auto-immune Profile
Antiphospholipid syndrome
5-B.M.A. in the presence of Atypical clinical features
or no response to Rx better before initiation of
steroid therapy
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PERIPHERAL BLOOD SMEAR
“GOLD STANDARD”
Check for platelet clumping, platelet size, RBC
morphology, presence of immature WBCs
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Deferential Diagnosis
Spurious
Congenital Thrombocytopenia
Fanconi anaemia
Aplastic anaemia
Acute leukemia
Autoimmune diseases (SLE)
Hypersplenism
Microangiopathy
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Management
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Important Points to consider:
Observation & follow up
Let the treatment fit the patient (treat cases
individually)
Evidence based medicine through randomized
controlled trials and or clinical practice
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Goal of the treatment
Not to achieve a normal platelet count but to
prevent bleeding
2 options:
1.
2.
Counseling and observation
or Rx if: low platelet and/or bleeding
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Management of ITP
Prednisone1-2 mg/kg daily
60-80% achieve remission
Intravenous immunoglobulin
0.4 g/kg daily x 5 days,
or 1 g/kg/d x 2 days
I.V. Anti-D
50-75 ug/kg
High dose Dexamethasone 40mg/Kg x 4 days for 6 cycles
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High dose methyle prednisolone (HDMP)
Oral 7 days course (30 mg/kg/d/3 days then 20
mg/kg/d x 4 days) x 6 courses
platelet count by day 7 > 50 x 104/L
Splenectomy
Introduced in 1916
Two thirds of patients achieve remission
ineffective medical management or/and therapy
associated toxicity
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Medical therapy after failed splenectomy
or refusal to allow splenectomy
• Oral prednisone (dose as presplenectomy)
• IVIg 0.8-1.0 g/kg; repeat once
if platelet
response at 48-72 hours
inadequate
• IV anti-D IV (Rh(D)-positive
patients only),
50-75g/kg
• Other (eg, azathioprine,
cyclophosphamide,
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vincristine,
danazol).
Emergency therapy
• IV methylprednisolone 30 mg/kg/d
(maximum, 1g) for 3 consecutive days
• IVIg (1-2 g/kg over 2 days)
• Platelet trasfusion
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Rarely used therapies
Interferon-
Cyclosporine A
Combination chemotherapy
Plasma exchange
Staphylococcal protein A immunoadsorption
Dapsone
Ascorbic acid
Colchicine
Mabthera
Danazol
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Immunosuppressive & Chemotherapy
Azathioprine, cyclosporine
Vincaalkaloid, cyclophosphamide
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Platelet Transfusion
Evaluate the case
Life threatened emergency
IVIG
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Follow-up
Clinical severity in addition to platelet count, CBC
should be repeated within 7-10 days of diagnosis
and only when there is a clinical indication or
signs of resolution of clinical symptoms.
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Conclusions
Learn from our mistakes
Observe the patients, treat only when it is really
needed.
Treat individual cases.
Platelet transfusion is contraindicated
Evidence based medicine randomized control trials for
management of ITP.
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References
Immune Thrombocytopenic Purpura Let the
treatment fit the patient, George, et al
Editorial – New England Journal of Medicine
January 13,2004.
Initial Treatment of Immune Thrombocytopenia
Purpura with high-dose dexamethasone Cheng,
et al, January 13, 2004.
Guidelines for the Investigation & Management
of Idiopathic Thrombocytopenic Purpura in
adult, children and in pregnancy, British Journal
of Haematology 2003.
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Pathogenesis and Management of Chronic Idiopathic
Thrombocytopenic Purpura An Update, Renchiyang,
Zhong Chao Han; International Journal of Haematology ,
Aug. 1999.
Blanchette V, Freedman J, Garvey B., Management of
Chronic ImmuneThrombocytopenic Purpura in Children
and Adults, Semin Haematol, 1998.
Idiopathic Thrombocytopenic Purpura: A Concise
Summary of the Pathophysiology and Diagnosis in
Children and Adults. James N. George & Gary E. Raskob;
Seminars in Haematology 1998.
George JN, Woolf SH, Raskob GE, et al: Idiopathic
Thrombocytopenic Purpura. A Practice Guideline
Developed by Explicit Methods For American Society of
Haematology Blood;88:3-40,1996.
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