Thanks to Connie for presenting the case of an elderly woman who presented with petechial bleeding, found to have a platelet count of 15, with work up revealing possible Evans’ Syndrome as well as bladder cancer!

Clinical Pearls

• Think of thrombocytopenia as a problem with platelet production, platelet destruction, sequestration, or lab problem.
• ITP is a diagnosis of exclusion. It can be a primary process due to autoimmune platelet destruction, or triggered by an associated condition (secondary ITP).
• Remember that decadron is superior to prednisone in treatment of ITP based on this meta-analysis.
• TPO mimetics are best as a last resort and more useful in maintenance of remission rather than inducing remission.

Thrombocytopenia DDx

• Decreased production
  • Aplastic anemia
  • MDS
  • Drugs
  • Alcohol
  • Cirrhosis
  • Leukemia
  • Severe megaloblastic anemia (folate/B12 deficiency)
  • Myelofibrosis
  • Granulomas
  • Solid malignancy mets to the bone
• Increased destruction
  • Immune mediated
    • Primary ITP
    • Secondary
      • Infection: HIV
      • Rheum d/o: SLE, APLS
      • Lymphoproliferative process: CLL, lymphomas
      • Drugs
      • Post-transfusion purpura (alloimmune process)
  • Non-immune mediated
    • MAHA (DIC, HUS/TTP)
    • Plavix
    • Vasculitis
    • HELLP
    • Infections: sepsis, CMV, EBV, malaria, rickettsia, ehrlichiosis, dengue, Hanta virus, etc.
    • CVVH
• Sequestration due to hypersplenism
• Pseudo-thrombocytopenia: clumping due to EDTA anticoagulated tubes (confirm by request blood draw in citrate coated tubes)

Thrombocytopenia work up

• Good history and review of meds, infections, prior history of autoimmune disorders
• Check CBC, coags and peripheral smear!
  • Spherocytes ⇒ AIHA, hypersplenism
  • Schistocytes ⇒ MAHA
  • Pancytopenia ⇒ aplastic anemia, MDS, leukemias, etc.

Immune Thrombocytopenic Purpura (ITP)

Check out our thorough post on this topic here.