Immune thrombocytopenic purpura: Difference between revisions
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==Background== | ==Background== | ||
*Abbreviation: ITP | |||
*Known as both "idiopathic" or "immune" thrombocytopenic purpura | |||
*Acquired autoimmune disease resulting in destruction of platelets | *Acquired autoimmune disease resulting in destruction of platelets | ||
*Because circulating | *Because circulating platelets are functional, life-threatening bleeding only once platelet count <10K | ||
*Types | *Chronically, the disease follows a course that is usually stable with intermittent and episodic flares, leading to clinically relevant thrombocytopenia<ref>Cines DB and Blanchette VS. Immune Thrombocytopenic Purpura. New England Journal of Medicine. Vol 346 (13); 995-1008.</ref> | ||
===Types=== | |||
{| {{table}} | |||
| align="center" style="background:#f0f0f0;"|'''Charateristic''' | |||
| align="center" style="background:#f0f0f0;"|'''Acute ITP''' | |||
| align="center" style="background:#f0f0f0;"|'''Chronic ITP''' | |||
|- | |||
| Common age group||Younger children||Adults | |||
|- | |||
| Sex||Affects men/women equally||Usually women | |||
|- | |||
| Duration||Resolves in 1-2 months||Lasts > 3 months | |||
|- | |||
|Cause||Typically follows viral illness||More likely to have an underlying disease or autoimmune disorder (e.g. SLE) | |||
|- | |||
| Prognosis||||Rarely remits spontaneously or with treatment | |||
|} | |||
==Clinical Features== | ==Clinical Features== | ||
*Petechiae | *[[Petechiae]] | ||
*Epistaxis | *[[Epistaxis]] | ||
*[[Gingival bleeding]] | |||
*[[Vaginal Bleeding (Non-Pregnant)|Menorrhagia]] | |||
*[[GI bleeding]] | |||
*[[Intracranial hemorrhage]] | |||
==Differential Diagnosis== | |||
{{Thrombocytopenia}} | |||
{{Purpura DDX}} | |||
== | ==Evaluation== | ||
*Diagnosis of exclusion | *Diagnosis of exclusion | ||
*Must differentiate acute ITP from chronic ITP, which suggests an underlying disorder | |||
*CBC shows normal cell lines except for the platelets (may have mild anemia) | *CBC shows normal cell lines except for the platelets (may have mild anemia) | ||
== | ==Management== | ||
===Options=== | ===Options=== | ||
*'''First choice in adults:''' Corticosteroids | |||
**[[Prednisone]] 60-100mg/d with taper after count reaches normal (50-75% remission rate by 3 wks) | |||
**[[Methylprednisolone]] 30mg/kg/d IV x 3 days (for life-threatening bleeding) | |||
*'''First choice in children:''' Intravenous Immunoglobulin G ([[IVIG]]) 1gm/kg/d x 2 days | |||
*High dose Anti-D ([[RhoGAM]]): patient must be Rh+ for it to work | |||
**Causes shift towards splenic destruction of antibody-coated Rh+ RBCs | |||
**Thereby has less functional capacity to destroy platelets | |||
**Dosage dependent on Hb level in mg/dL<ref>eMedicine. RhoGAM. http://reference.medscape.com/drug/rhogam-hyperrho-s-d-rho-d-immune-globulin-343143.</ref> | |||
***Hb>10, 250 IU/kg IV x1 over 5min | |||
***Hb<10, 125 IU/kg IV x1 over 5min | |||
*[[Platelet transfusion]] | |||
**Indicated for life-threatening bleeding | |||
**Will ultimately be destroyed | |||
**Transfuse only following first dose of [[methylprednisolone]] or [[IVIG ]] | |||
***Holding transfusion until after first dose results in greater rise in platelet count | |||
***Calculate number of packs needed to increase count to over 50k (1 pack generally increases by 10k) | |||
*Estrogen for uterine bleeding: 25mg IV x1 | |||
===Indications=== | ===Indications=== | ||
====Adults==== | ====Adults==== | ||
*Platelet >30K and asymptomatic: usually do not require treatment | |||
*Platelet count <30K: [[prednisone]] | |||
*Platelet <50K AND bleeding: [[prednisone]] | |||
*Life-threatening bleeding: IVIG, methylprednisolone, platelet transfusion | |||
====Children==== | ====Children==== | ||
*Platelet count >30K: usually do not require treatment | |||
*Platelet count <20K + significant bleeding: IVIG | |||
*Platelet count <10K: IVIG | |||
*Life-threatening bleeding: IVIG, methylprednisolone, platelet transfusion | |||
===Other Options=== | |||
*[[Splenectomy]] if above fails (only 2/3 effective) | |||
*[[Rho(D) Immune Globulin (RhoGAM)]] | |||
**Will induce mild hemolysis in Rh+ patients that decreases macrophage activity | |||
**Spleen will not destroy platelets covered in antibodies | |||
*[[Rituximab]] | |||
**May help as ITP is autoimmune process | |||
==Disposition== | ==Disposition== | ||
*'''Admit:''' platelet count <20K or significant mucous membrane bleeding | |||
*'''Discharge:''' platelet count >20K AND asymptomatic '''OR''' only minor petechiae | |||
==Complications== | ==Complications== | ||
*Rare: more common in elderly | |||
**[[Intracerebral bleeding]] | |||
**Severe [[GI bleeding]] | |||
== | ==See Also== | ||
* | *[[ITP in Pregnancy]] | ||
==References== | |||
<references/> | |||
[[Category:Heme/Onc]] | [[Category:Heme/Onc]] |
Revision as of 14:49, 1 September 2019
Background
- Abbreviation: ITP
- Known as both "idiopathic" or "immune" thrombocytopenic purpura
- Acquired autoimmune disease resulting in destruction of platelets
- Because circulating platelets are functional, life-threatening bleeding only once platelet count <10K
- Chronically, the disease follows a course that is usually stable with intermittent and episodic flares, leading to clinically relevant thrombocytopenia[1]
Types
Charateristic | Acute ITP | Chronic ITP |
Common age group | Younger children | Adults |
Sex | Affects men/women equally | Usually women |
Duration | Resolves in 1-2 months | Lasts > 3 months |
Cause | Typically follows viral illness | More likely to have an underlying disease or autoimmune disorder (e.g. SLE) |
Prognosis | Rarely remits spontaneously or with treatment |
Clinical Features
Differential Diagnosis
Thrombocytopenia
Decreased production
- Marrow infiltration (tumor or infection)
- Viral infections (rubella, HIV)
- Marrow suppression (commonly chemotherapy or radiation)
- Congenital thrombocytopenia
- Fanconi anemia
- Alport syndrome
- Bernand Soulier
- Vitamin B12 and/or folate deficiency
Increased platelet destruction or use
- Idiopathic thrombocytopenic purpura
- Thrombotic Thrombocytopenic Purpura (TTP)
- Hemolytic Uremic Syndrome (HUS)
- Disseminated Intravascular Coagulation (DIC)
- Viral infections (HIV, mumps, varicella, EBV)
- Drugs (heparin, protamine)
- Postransfusion or Posttransplantation
- Autoimmune destruction (SLE or Sarcoidosis)
- Mechanical destruction
- Artificial valves
- ECMO
- HELLP syndrome
- Excessive hemorrhage
- Hemodialysis, extracorporeal circulation
- Splenic Sequestration
- Occurs in Sickle cell disease and Cirrhosis
Drug Induced
- sulfa antibiotics, ETOH, ASA, thiazide diuretics/furosemide
Comparison by Etiology
ITP | TTP | HUS | HIT | DIC | |
---|---|---|---|---|---|
↓ PLT | Yes | Yes | Yes | Yes | Yes |
↑PT/INR | No | No | No | +/- | Yes |
MAHA | No | Yes | Yes | No | Yes |
↓ Fibrinogen | No | No | No | No | Yes |
Ok to give PLT | Yes | No | No | No | Yes |
Petechiae/Purpura (by cause)
- Abnormal platelet count and/or coagulation
- Septicemia
- Idiopathic thrombocytopenic purpura (ITP)
- Hemolytic uremic syndrome
- Leukemia
- Coagulopathies (e.g. hemophilia)
- Henoch-Schonlein Purpura (HSP)
- Acute hemorrhagic edema of infancy (AHEI)
- Hypersensitivity vasculitis
- Primary vasculitides
- Wegener's
- Microscopic polyangiitis
- Eosinophilic granulomatosis with polyangiitis (Churg-Strauss syndrome)
- Secondary vasculitides
- Trauma
Evaluation
- Diagnosis of exclusion
- Must differentiate acute ITP from chronic ITP, which suggests an underlying disorder
- CBC shows normal cell lines except for the platelets (may have mild anemia)
Management
Options
- First choice in adults: Corticosteroids
- Prednisone 60-100mg/d with taper after count reaches normal (50-75% remission rate by 3 wks)
- Methylprednisolone 30mg/kg/d IV x 3 days (for life-threatening bleeding)
- First choice in children: Intravenous Immunoglobulin G (IVIG) 1gm/kg/d x 2 days
- High dose Anti-D (RhoGAM): patient must be Rh+ for it to work
- Causes shift towards splenic destruction of antibody-coated Rh+ RBCs
- Thereby has less functional capacity to destroy platelets
- Dosage dependent on Hb level in mg/dL[2]
- Hb>10, 250 IU/kg IV x1 over 5min
- Hb<10, 125 IU/kg IV x1 over 5min
- Platelet transfusion
- Indicated for life-threatening bleeding
- Will ultimately be destroyed
- Transfuse only following first dose of methylprednisolone or IVIG
- Holding transfusion until after first dose results in greater rise in platelet count
- Calculate number of packs needed to increase count to over 50k (1 pack generally increases by 10k)
- Estrogen for uterine bleeding: 25mg IV x1
Indications
Adults
- Platelet >30K and asymptomatic: usually do not require treatment
- Platelet count <30K: prednisone
- Platelet <50K AND bleeding: prednisone
- Life-threatening bleeding: IVIG, methylprednisolone, platelet transfusion
Children
- Platelet count >30K: usually do not require treatment
- Platelet count <20K + significant bleeding: IVIG
- Platelet count <10K: IVIG
- Life-threatening bleeding: IVIG, methylprednisolone, platelet transfusion
Other Options
- Splenectomy if above fails (only 2/3 effective)
- Rho(D) Immune Globulin (RhoGAM)
- Will induce mild hemolysis in Rh+ patients that decreases macrophage activity
- Spleen will not destroy platelets covered in antibodies
- Rituximab
- May help as ITP is autoimmune process
Disposition
- Admit: platelet count <20K or significant mucous membrane bleeding
- Discharge: platelet count >20K AND asymptomatic OR only minor petechiae
Complications
- Rare: more common in elderly
See Also
References
- ↑ Cines DB and Blanchette VS. Immune Thrombocytopenic Purpura. New England Journal of Medicine. Vol 346 (13); 995-1008.
- ↑ eMedicine. RhoGAM. http://reference.medscape.com/drug/rhogam-hyperrho-s-d-rho-d-immune-globulin-343143.