Idiopathic thrombocytopenic purpura pathophysiology: Difference between revisions
Jump to navigation
Jump to search
Nabeel ahmed (talk | contribs) No edit summary |
Nabeel ahmed (talk | contribs) No edit summary |
||
| Line 6: | Line 6: | ||
==Pathophysiology== | ==Pathophysiology== | ||
* | * Most common cases of ITP is [[autoimmune]] .<ref>{{cite journal |author=Coopamah M, Garvey M, Freedman J, Semple J |title=Cellular immune mechanisms in autoimmune thrombocytopenic purpura: An update |journal=Transfus Med Rev |volume=17 |issue=1 |pages=69–80 |year=2003 |pmid=12522773}}</ref> | ||
* Auto [[antibodies]] against platelets | * Auto [[antibodies]] against platelets is detected in approximately 60% patients . | ||
* | * These antibodies are against platelet membrane [[glycoprotein]]s IIb-IIIa or Ib-IX, and [[IgG]] type.<ref name="pmid18046034">{{cite journal |author=Schwartz RS |title=Immune thrombocytopenic purpura--from agony to agonist |journal=N. Engl. J. Med. |volume=357 |issue=22 |pages=2299–301 |year=2007 |pmid=18046034 |doi=10.1056/NEJMe0707126}}</ref> | ||
* Other cause of ITP is | * Other cause of ITP is due to chronic infections such as HIV, hepatitis C and H. Pylori. It,s due to molecular mimicry, antibody is formed against the infection and this cross-reacts with platelets. Autoantibodies in ITP react with platelet IIb/IIIa glycoprotein, less commonly with GPIb/IX. Lymphocytes in the spleen make the antiplatelet antibody; that,s why splenectomy works so well. There is a correlation between a platelet's short survival and high turnover rate and the subsequent excellent response to [[splenectomy]]. | ||
* Platelet kinetic studies show that platelet production is normal or reduced rather than increased in about two thirds of ITP patients. | * Platelet kinetic studies show that platelet production is normal or reduced rather than increased in about two thirds of ITP patients. | ||
* [[autoantibodies]] from patients with ITP inhibit megakaryocyte growth in vitro. | * [[autoantibodies]] from patients with ITP inhibit megakaryocyte growth in vitro. | ||
Revision as of 22:21, 30 July 2018
|
Idiopathic thrombocytopenic purpura Microchapters |
|
Differentiating Idiopathic thrombocytopenic purpura from other Diseases |
|---|
|
Diagnosis |
|
Treatment |
|
Case Studies |
|
Idiopathic thrombocytopenic purpura pathophysiology On the Web |
|
American Roentgen Ray Society Images of Idiopathic thrombocytopenic purpura pathophysiology |
|
Idiopathic thrombocytopenic purpura pathophysiology in the news |
|
Blogs on Idiopathic thrombocytopenic purpura pathophysiology |
|
Directions to Hospitals Treating Idiopathic thrombocytopenic purpura |
|
Risk calculators and risk factors for Idiopathic thrombocytopenic purpura pathophysiology |
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]
Overview
Pathophysiology
- Most common cases of ITP is autoimmune .[1]
- Auto antibodies against platelets is detected in approximately 60% patients .
- These antibodies are against platelet membrane glycoproteins IIb-IIIa or Ib-IX, and IgG type.[2]
- Other cause of ITP is due to chronic infections such as HIV, hepatitis C and H. Pylori. It,s due to molecular mimicry, antibody is formed against the infection and this cross-reacts with platelets. Autoantibodies in ITP react with platelet IIb/IIIa glycoprotein, less commonly with GPIb/IX. Lymphocytes in the spleen make the antiplatelet antibody; that,s why splenectomy works so well. There is a correlation between a platelet's short survival and high turnover rate and the subsequent excellent response to splenectomy.
- Platelet kinetic studies show that platelet production is normal or reduced rather than increased in about two thirds of ITP patients.
- autoantibodies from patients with ITP inhibit megakaryocyte growth in vitro.
- IgG from ITP-plasma inhibits megakaryocyte production.
- Ultrastructural studies of the bone marrow in ITP show increased signs of megakaryocyte apoptosis and reduced platelet shedding.
- Recent studies suggests that the stimulus for autoantibody production in ITP is due to abnormal T helper cells reacting with platelet antigens on the surface of antigen presenting cells.[3] This important finding suggests that therapies directed towards T cells may be effective in treating ITP.[4]
References
- ↑ Coopamah M, Garvey M, Freedman J, Semple J (2003). "Cellular immune mechanisms in autoimmune thrombocytopenic purpura: An update". Transfus Med Rev. 17 (1): 69–80. PMID 12522773.
- ↑ Schwartz RS (2007). "Immune thrombocytopenic purpura--from agony to agonist". N. Engl. J. Med. 357 (22): 2299–301. doi:10.1056/NEJMe0707126. PMID 18046034.
- ↑ Semple JW, Freedman J (1991). "Increased antiplatelet T helper lymphocyte reactivity in patients with autoimmune thrombocytopenia". Blood. 78 (10): 2619–25. PMID 1840468.
- ↑ Zufferey A, Kapur R, Semple JW (February 2017). "Pathogenesis and Therapeutic Mechanisms in Immune Thrombocytopenia (ITP)". J Clin Med. 6 (2). doi:10.3390/jcm6020016. PMC 5332920. PMID 28208757.