Chronic itp
- 1. CHRONIC ITP By DR Falak abro
- 2. • chronic ITP persists for more than 6- 12 months. • Chronic ITP has more insidious onset with easy bruising and petechiae •Age 8-14 years. • male : female ratio is 1:2
- 4. PATHOPHYSIOLOGY • Increased platelet destruction . • Spleen is key organ in Pathophysiology .platelet autoantibodies formed in white pulp . Macrophages in red pulp destroy immunoglobulin coated platelets.
- 5. PATHOPHYSIOLOGY •Autoantibody coated platelets induce Fc receptor-mediated phagocytosis by mononuclear macrophages
- 7. *Bruise
- 8. Petechiae
- 10. PurPura
- 13. Epistaxsis
- 14. INVESTIGATION
- 15. PERIPHERAL BLOOD FILM • ITP with low platelet count usually (<100,000 usually) with normal hemoglobin and WBC count • thrombocytopenia with platelet count <20 x 109/L is common and platelet size may be normal or increased
- 17. •The bone marrow in patients with ITP contains normal or increased number of megakaryocytes indicates that : a: plateletes production is normal b: thrombocytpenia is due to increased platelet destruction.
- 20. TREATMENT
- 21. • Wait and Watch if platelets are below 50,000 or there is no signs of bleeding.
- 22. INTRAVENOUS IMMUNOGLOBULINS •Mechanism: blocking FC receptors of RE (reticuloendothelial) phagocytes. • preventing them from binding and destroying IgG antibody-coated platelets.
- 24. LNH PHARMACY 1 vial= 250 mg Price= approx Rs: 1500
- 25. Dose : safe dose is 400mg/kg/day using 5 days continuously or 1g/kg/day for 2 days. Merits: IVIG is preferable to steroids because it causes faster elevation of platelete count greater than 20,000 within 24 hours.
- 26. Demerits : • Its expensive • Long infusion time of 6-8 hours • Headache • vomiting
- 27. Corticosteroids: Mechanism • inhibit platelet destruction. •Rapid action that reduces RE destruction of antibody coated platelet.
- 28. Dose: •Oral prednisone 1-2mg/kg/day for two weeks then tapered over third week • In chronic ITP with recurrent bleeding intravenous methyl predinisolone 20-30mg/kg/day for 3 days can be given.
- 29. Intravenous Anti D therapy : MECHANISM: • Specific red blood cell antibodies coat red blood cells, which are taken by RE system in place of antibody coated platelets. •Anti Rh-D immunoglobulin produces mild hemolytic anemia that saturates Fc receptors of phagocytic elements of RE system.
- 30. •Dose I/V 50ug -75ug/kg for two days platelet rise within 48 hours to 72 hours. •Merits: Lower side effects than IVIG doesnot cause headach or vomiting •Demerit: causes hemolysis.
- 31. LNH PHARMACY 1 vial= 300 ug Price = RS: 5500
- 32. SPLEENECTOMY: •Indicated in chronic, symptomatic ITP when other options fail. •About 64-88% of patient with chronic Itp achieve complete remission.
- 33. It is done because It removes: • primary site of platelete destruction and site of antiplatelete-antibody production
- 34. RITUXIMAB: MECHANISM: • it is monoclonal antibody which depletes B-cells by binding to the CD-20 antigen surface •Therapy effect remains for 6-12 months as it prevents activity of autoreactive cells specially against gp-IIb/IIIa.
- 35. Dose : 375mg/m2 per dose weekly for 4 weeks. Price : 100mg vial approx RS: 17000 500mg vial approx RS: 85000
- 36. Time to respond therapy : 1-7 weeks Side-effects: fever, chills, allergy reactions which can be prevented by slow infusion and premedication with antihistamine or steroids.
- 37. (Thrombopoeitin) TPO receptor agonists •Mechanism of action •Endogenous TPO made in liver which regulates platelet production by increasing the number and maturation of bone marrow megakaryocytes. •2 TPO receptor agonists : a: romiplostim with dose 1-10ug/kg/dose subcutanously weekly. b: Eltrombopag with dose is 50mg orally.
- 38. •ROMIPLOSTIM is a subcutaneous thrombopoiesis stimulating FC-peptide fusion protein. •ELTROMBOPAG is orally active non peptide agonist, it acts by stimulating platelet production.
- 39. Side effects • Romiplostim : headache, phyrangitis, fatigue •Eltrombopag : nausea and vomiting, hepatic toxicity
- 41. THANKYOU…