risk for hemorrhage; hemorrhagic diathesis; bleeding disorder

Introduction

An inherited or acquired tendency to bleed, including:

• coagulation disorders
• platelet disorders

Etiology

• coagulation disorders
  • liver disease
    • increased risk of bleeding & thrombosis
      • decreased coagulation factors, vitamin K
      • decreased protein C, protein S & antithrombin
      • diminished & dysfunctional fibrinogen
  • coagulation factor deficiency
    • hemophilia A, hemophilia B
• coagulation factor inhibitor
  • pregnancy, post partum, systemic lupus erythematosus, malignancy
• disseminated intravascular coagulation
  • prolonged PT & aPTT, low plasma fibrinogen, high plasma D-dimer, schistocytes on peripheral smear
• platelet disorders
  • thrombocytopenia
  • von Willebrand disease
  • thrombotic thrombocytopenic purpura - hemolytic uremic syndrome
  • heparin-induced thrombocytopenia

Pathology

• primary or secondary defect in hemostasis
  • primary hemostasis involves formation of platelet plug at the site of vascular injury
  • secondary hemostasis occurs from exposure of tissue factor at the site of vascular injury with initiation of the coagulation cascade

Clinical manifestations

• failure of primary hemostasis (platelet disorder)
  • mucocutaneous bleeding
    • epistaxis, gingival bleeding, easy bruising, menorrhagia
• failure of secondary hemostasis (coagulation disorder)
  • bleeding into muscles & joints
  • delayed bleeding

Laboratory

• prothrombin time (PT) & activated partial thromboplastin time (aPTT)*
• mixing study if prolonged aPTT to distinguish coagulation factor deficiency from coagulation factor inhibitor (deficiency completely corrects)
• bleeding time identifies platelet disorders & vascular integrity
• platelet function testing as indicated
• thrombin time: conversion of fibrinogen to fibrin
• D-dimer in plasma identifies disseminated intravascular coagulation associated with excessive fibrinolysis

* see prothrombin time, activated partial thromboplastin time or coagulation disorder for differential diagnosis of PT & aPTT values

Complications

• excessive bleeding after childbirth, surgery or trauma can occur from failure of primary or secondary [1]hemostasis

More general terms

• health risk factor(s)

More specific terms

• coagulation disorder; coagulopathy
• hereditary bleeding disorder
• platelet disorder; thromboasthenia