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Similar a Causes of Thrombocytopenia in pediatrics other than ITP
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Causes of Thrombocytopenia in pediatrics other than ITP
- 1. Causes of Thrombocytopenia in pediatrics other than ITPPrepared by:- Asmaa Rabie Abdel Monem A 5th grade med student Alexandria University Faculty of Medicine
- 2. Causes of thrombocytopenia increased destruction Immune mechanism Iodopathic (ITP) Secodary to infection, drugs, SLE Non-immune mechanism platelet consumption DIC ,HUS microangiopathic hemolytic anemia platelet destruction Hypersplenism , drugs Prothetic heart valve sequesteration Large spleen Decreased production Bone marrow depression Hereditary Fanconi anemia TAR syndrome Acquired Drugs , chemotherapy Inefction, hepatitis ,HIV ,EBV Bone marrow infiltration Leukemia ,neuroblastoma Storage disease
- 3. Secondary immune mechanism Drug-Induced Thrombocytopenia •A number of drugs are associated with immune thrombocytopenia as the result of either an immune process or a megakaryocyte injury.
- 4. Heparin-induced hrombocytopenia (and rarely thrombosis) is seldom seen in pediatrics but occurs when, after exposure to heparin, the patient develops an antibody directed against the heparin/ platelet factor IV complex.
- 5. Non immune Platelet Destruction increase platelet consumption DIC hemolytic-uremic syndrome thrombotic thrombocytopenic purpura The syndromes of DIC, hemolytic-uremic syndrome, and thrombotic thrombocytopenic purpura share the hematologic picture of The microangiopathic hemolytic anemia is characterized by the presence of RBC fragments, including helmet cells, schistocytes, spherocytes, and burr cells.
- 6. Hemolytic-Uremic Syndrome (HUS) Abnormal red cell morphology Normal numbers of megakaryocytes.
- 8. Combined Platelet and Fibrinogen Consumption Syndromes Kasabach-Merritt Syndrome Hemangioma platelet trapping and activation of coagulation with fibrinogen consumption and generation of fibrin(ogen)
- 9. Non immune Platelet Destruction Sequestration •Individuals with massive splenomegaly develop thrombocytopenia, since the spleen acts as a sponge for platelets and sequesters large numbers. •Most such patients will also have mild leukopenia and anemia on the CBC. Individuals who have thrombocytopenia caused by splenic sequestration should undergo a work- up to diagnose the etiology of splenomegaly, including infectious, infiltrative, neoplastic, obstr uctive, and hemolytic causes.
- 10. Thrombocytopenia - Underproduction Marrow failure: myelodysplasia, aplastic anemia, vitamin deficiencies. Marrow infiltration: tumor, granulomatous diseases, fibrosis, leukemias, lymphomas Marrow toxins: drugs, radiation, infections (CMV, HIV), alcohol.
- 11. Congenital Thrombocytopenic Syndromes Congenital Amegakaryocytic thrombocytopenia Bone marrow transplant is curative. Bone marrow failure absence of megakaryocytes in bone marrow examination.
- 12. Thrombocytopenia–absent radius (TAR) The thrombocytopenia of TAR syndrome frequently remits over the first few years of life.
- 13. Fanconi anemia Aplastic anemia not present at birth, develops about 6 yr of age; fatal without bone marrow transplant; chromosomal breakage challenge test available for early diagnosis.
- 14. Wiskott-Aldrich syndrome (WAS) Microthrombocytopenia Eczema Recurrent infections X-linked Normal number of megakaryocytes Successful bone marrow transplantation cures WAS. Microthrombocytes
- 15. Refrences 1. Nelson textbook of pediatrics 19th edition, Chapter 476. 2. Dan L. Longo, HARRISON’S Hematology and Oncology; 3. Childhood idiopathic thrombocytopenic purpura (itp): over 40 year of experiences; Medical Journal of Islamic World Academy of Sciences 19:4, 151-160, 2011. -http://www.uptodate.com/contents/clinical.4 -of-evaluation-and-manifestations children-in-thrombocytopenia
Notas del editor
- HSM, hepatosplenomegaly; ITP, idiopathicimmune thrombocytopenic purpura; NATP, neonatal alloimmune thrombocytopenicpurpura; SLE, systemic lupus erythematosus; TAR, thrombocytopenia-absent radius;TTP, thrombotic thrombocytopenic purpura; UAC, umbilical artery catheter; VWD, vonWillebrand disease; WBC, white blood cell.
- Some common drugs used in pediatrics that cause thrombocytopenia include valproic acid, phenytoin, sulfonamides, and trimethoprim-sulfamethoxazole.
- http://www.uptodate.com/contents/drug-induced-thrombocytopenia
- thrombotic microangiopathy in which there is red cell destruction and a consumptive thrombocytopenia caused by platelet and fibrin deposition in the microvasculature
- This acute disease usually follows an episode of acute gastroenteritis, often triggered by Escherichia coli 0157:H7. Shortly thereafter, signs and symptoms of hemolytic anemia, thrombocytopenia, and acute renal failure ensue. Sometimes neurologic symptoms are associated with these findings. E.coli 0157:H7 produces a specific toxin (verotoxin) that binds to and damages renal endothelial cells preferentially.
- The association of a giant hemangioma with localized intravascular coagulation causing thrombocytopenia and hypofibrinogenemia is called the Kasabach-Merritt syndrome. In most patients the site of the hemangioma is obvious, but retroperitoneal and intra-abdominal hemangiomas may require body imaging for detection. Inside the hemangioma there is platelet trapping and activation of coagulation with fibrinogen consumption and generation of fibrin(ogen) degradation products. Arteriovenous malformation within the lesions can cause heart failure.The peripheral blood smear shows microangiopathic changes. Multiple modalities have been used to treat Kasabach-Merritt syndrome, including surgical excision , laser photocoagulation, corticosteroids in high doses, local x-ray therapy, and antiangiogenic agents such as interferon a2 . Over time most patients who present in infancy have regression of the hemangioma.
- Congenital amegakaryocytic thrombocytopenia is caused by a rare defect in hematopoiesis that usually manifests within the first few days to weeks of life, when the child presents with petechiae and purpura caused by profound thrombocytopenia. Other than skin and mucous membrane findings, the physical examination is normal.
- syndrome consists of thrombocytopenia that presents in early infancy with radial anomalies of variable severity from mild changes to marked limb shortening. In many such individuals there are also other skeletal abnormalities of the lower extremities.Intolerance to formula may complicate management by triggering gastrointestinal bleeding.
- microcephaly, microphthalmia, epicanthal folds, dangling thumbs, site of ureteralreimplantation, congenital dislocated hips, and rocker bottom feet. (Alter BP, Young NS. The bone marrow failure syndromes.
- is characterized by thrombocytopenia with tiny platelets, eczema, and recurrent infections due to immune deficiency. WAS is inherited as an X-linked disorder. The WAS protein appears to play an integral role in regulating the cytoskeletal architecture of both platelets and T lymphocytes in response to receptor-mediated cell signaling. The WAS protein is common to all cells of hematopoietic lineage. Molecular analysis of families with X-linked thrombocytopenia has shown that many members have a point mutation within the WAS gene, whereas individuals with the full manifestation of WAS have large gene deletions. Examination of the bone marrow in WAS shows the normal number of megakaryocytes, although the megakaryocytes may have bizarre morphology. Transfused platelets have a normal life span. Splenectomy often corrects the thrombocytopenia, suggesting that the platelets formed in WAS have accelerated destruction. About 5% of WAS patients develop lymphoreticular malignancies. Successful bone marrow transplantation cures WAS.