Clinical Practice Guidelines

Immune Thrombocytopenic Purpura

  • Background

    ITP is an acquired thrombocytopenia due to immune mediated shortened circulating platelet survival in the absence of other disturbances of haemostasis or coagulation. In most childhood ITP platelet autoantibodies are absent.

    Patients fall broadly into two categories:

    1. Acute (~ 90%): self limiting disease (sometimes preceded by a viral syndrome) with spontaneous resolution within 6 months (usually within 2 months).
    2. Chronic (~ 10%): does not remit within 6 months.
    • Most children present with bruising and petechiae alone.
    • In some instances there is oral bleeding, epistaxis, rectal bleeding or haematuria.
    • Morbidity in ITP is usually minimal and parents need to be reassured of this.
    • The incidence of intracranial haemorrhage is much less than 1%, and very rare in true uncomplicated ITP.

    Assessment

    • The clinical diagnosis of ITP depends on there being manifestations of thrombocytopenia without other abnormal findings, in particular no pallor, lymphadenopathy or hepatosplenomegaly.
    • Confirmation rests on the adequate exclusion of other causes of thrombocytopenia. The most important conditions to exclude are acute leukaemia, other marrow infiltrative conditions and aplastic anaemia. An FBE (including blood film) will usually confirm the diagnosis.
    • A bone marrow aspirate is an invasive procedure with some morbidity in children who bruise easily, and is only necessary if the diagnosis is uncertain. It is rarely necessary in uncomplicated ITP.

    Management

    Initial treatment options include no treatment and oral steroids.

    Without active treatment, most patients platelet counts will return to a level at which normal activity can be recommenced within 4-6 weeks. Oral steroids bring up the platelet count more quickly than occurs spontaneously but there is no evidence for an effect on significant morbidity, risk of chronic ITP, or mortality.

    At RCH, the on-call General Paediatric consultant is responsible for deciding on the treatment plan.

    a) Conservative Outpatient Management

    Most patients with a platelet count > 20 x 109/l and some of those with a platelet count < 20 x 109/l can be managed as outpatients with no specific treatment. The following criteria must be met:

    • The diagnosis is unequivocal. No pallor, hepatosplenomegaly or lymphadenopathy; isolated thrombocytopenia without anaemia, leucopenia or blood film changes.
    • There is no active bleeding. Bruising and petechiae in isolation, without mucosal, gastrointestinal or renal tract bleeding.
    • The child is otherwise well.
    • Social circumstances allow confidence about the degree of parental supervision and relative safety of the home environment, particularly for younger children.
    • There is ample opportunity for parental reassurance and education in the Emergency Dept.
    • Follow up is guaranteed within a few days by the on call General Paediatric consultant, who must be contacted and agree with the management plan.

    b) Conservative Inpatient Management

    1. If the diagnosis of ITP is not certain (eg. the blood film result is not available) or any other of the above criteria are not met, then admission under the General Medical unit of the day is necessary.
    2. The decision as to whether to treat patients who do not have active bleeding will be made by the unit consultant.

    Treatment As An Inpatient

    1. Any patient with ITP who has active bleeding (oral, aural, nasal, rectal, etc) even if resolved should be admitted and considered for oral prednisolone (2-4 mg/kg/day for 2 weeks then tapered).

      Normal human immunoglobulin is also effective but is not usually used for initial treatment ( Administration of Intragam Guideline)

      Avoid aspirin and non-steroidal anti-inflammatory drugs.

    Notes

    Acute, relapsing ITP

    In some cases, thrombocytopenia will redevelop months or years after the first episode has resolved. These relapses or recurrences are usually precipitated by viral infections. Provided the first episode remitted spontaneously without complication and the patient has been well with a documented normal platelet count between episodes, these cases can be managed as for acute ITP.

    Chronic ITP

    Ongoing thrombocytopenia after a 6 month period denotes chronic ITP. A history of bruising from infancy should prompt suspicion of one of the rare congenital thrombocytopenias. Careful inspection of the blood film and tests of platelet function will serve to exclude other diagnoses. Bone marrow examination may behelpful in confirming chronic ITP.

    Rarely, splenectomy is required (success rate 70-80%).

    See also ITP Parent Information Sheet  (HTML version)

    ITP Parent Information Sheet  (Print version - PDF)