IDIOPATHIC THROMBOCYTOPENIC PURPURA

• Also known as Immune thrombocytopenia (ITP)
• ITP is an acute or chronic bleeding disorder that results from immune destruction of platelets by antiplatelet antibodies.

Etiology

• Exact cause unknown; may be autoimmune.
• Spleen is the site for destruction of platelets
• It is more common among children and young women.
• Acute disorder
  • More common in childhood,
  • Typically following viral illness (URTI or Measles & chickenpox)
  • This is self-limited;
  • Remission often occurs spontaneously within 6 months.
• Chronic disorder
  • More than 6-month course
  • Most common between ages 20 and 50 years,
  • Three times more common in women,
  • May last for years or even indefinitely.
  • May be associated with
    • Pregnancy
    • Development of systemic lupus erythematosus,
    • Thyroid disease,
    • Infections like Helicobacter pylori, cytomegalovirus, varicella zoster, hepatitis C and HIV
    • Malignancy - Chronic lymphocytic leukaemia.

Clinical Manifestations

• May have asymptomatic with mild disease (with platelet counts 20,000 to 100,000/mm³).
• When platelet count drops below 20,000/mm³:
  • Bruising and Petechiae (dry purpura)
  • Nasal, gingival bleeding, & haemoptysis (wet purpura)
  • Menorrhagia.

Diagnostic Evaluation

• CBC with platelet count—decreased (less than 100,000/mm³) may also be lymphocytosis and eosinophilia.
• Bone marrow aspirate shows increased numbers of young megakaryocytes, increased numbers of eosinophils.
• Platelet aggregation test for heparin-dependent platelet antibodies—positive.
• Testing for Hepatitis C, HIV, Helicobacter pylori, and Epstein-Barr virus, which have been found to be associated with ITP.
• Bleeding times are typically normal.

Medical Management

• The primary goal of treatment is a "safe" platelet count.
• Supportive care: judicious use of platelet transfusions, control of bleeding.
• High-dose corticosteroids, IV immunoglobulins, parenteral anti-D (for Rhesus-positive patients with spleens).
• Thrombopoietin receptor agonists may be used to treat patients at risk for bleeding with chronic or relapsed ITP.
• Splenectomy removes potential site for sequestration and destruction of platelets and is used to treat chronic refractory ITP in adults.

Nursing management

Risk for Injury related to bleeding due to thrombocytopenia.

• Institute bleeding precautions.
  • Avoid use of plain razor, hard toothbrush or floss, I.M. injections, tourniquets, rectal procedures, suppositories.
  • Administer stool softeners, as necessary, to prevent constipation.
  • Restrict activity and exercise when platelet count is less than 20,000/mm3 or when active bleeding occurs.
• Monitor pad count and amount of saturation during menses;
• Administer or teach self-administration of hormones to suppress menstruation, as prescribed.
• Administer blood products, as ordered.
• Monitor for signs and symptoms of allergic reactions, anaphylaxis, and volume overload.
• Evaluate urine, stools, and emesis for gross and occult blood.