Immune thrombocytopenic purpura

Revision as of 09:24, 12 October 2011 by Jswartz (talk | contribs)

Background

  • Acquired autoimmune disease resulting in destruction of platelets
  • Because circulating plts are functional, significant bleeding usually only once plt <30K
  • Types
    • Acute
      • More common among younger children
      • Affects men/women equally
      • Resolves in 1-2mo
    • Chronic
      • Lasts >3mo
      • More common in adults and women
      • Rarely remits spontaneously or with tx
      • More likely to have an ynderlying disease or autoimmune disorder (e.g. SLE)

Clinical Features

  • Petechiae
  • Epistaxis, ginigival bleeding, menorrhagia

Diagnosis

  • Diagnosis of exclusion
    • Must differentiate from chronic ITP, which suggests an underlying disorder
  • CBC shows normal cell lines except for the platelets (may have mild anemia)

Treatment

Options

    1. Corticosteroids
      1. First-line in adults
      2. Prednisone 60-100 mg/d w/ taper after count reaches normal
      3. Methylprednisolone 30mg/kg/d IV x3d (for life-threatening bleeding)
    2. IVIG
      1. First-line in children
      2. 1gm/kg/d x2d
    3. Anti-D (RhoGAM)
      1. Pt must be Rh+ for it to work
    4. Transfusion (platelets)
      1. Indicated for life-threatening bleeding
      2. Transfuse only following first dose of methylprednisolone or IVIG
        1. Holding transfusion until after first dose results in greater rise in plt count
    5. Estrogen (uterine bleeding)
      1. 25mg IV x1

Indications

Adults

  1. Plt >30K and asymptomatic: Usually do not require treatment
  2. Plt count <30K: Prednisone
  3. Plt <50K AND bleeding: Prednisone
  4. Life-threatening bleeding
    1. IVIG, methylprednisolone, platelet transfusion

Children

  1. Plt count >30K: Usually do not require treatment
  2. Plt count <20K + significant bleeding: IVIG
  3. Plt count <10K: IVIG
  4. Life-threatening bleeding
    1. IVIG, methylprednisolone, platelet transfusion

Disposition

  1. Admit:
    1. Pts w/ plt count <20K or those who have significant mucous membrane bleeding
  2. Discharge:
    1. Plt counts >20K AND asymptomatic or have only minor petechiae

Complications

  1. Rare; more common in elderly
    1. Intracerebral bleeding
    2. Severe GI bleeding

Source

Tintinalli