Bleeding disorders

Bleeding disorders 

Updated: 09/16/2020

© Jun Wang, MD, PhD

Hemostasis
  • Primary: Vasoconstriction, platelet activation
  • Secondary: Coagulation cascades
  • Results: Blood clot formation
Activation of platelets

Coagulation system
  • Intrinsic pathway: XII, XI, IX, VIII (8-12 except 10)
  • Extrinsic pathway: VII
  • Common pathway: X, V, prothrombin (II), fibrinogen (I) (4 smallest US dollar bills)
Etiology of bleeding disorders
  • Vascular dysfunction, including vitamin C deficiency, telangiectasia, allergic purpura, purpura associated with infections such as meningococcus and Rocky Mountain spotted fever, etc
  • Platelet disorders
Thrombocytopenia
Thrombocytosis
Platelet dysfunctions associated with uremia, MDS, medications (NSAIDs etc) Bernard-Soulier syndrome, etc
    Coagulopathy
Von Willebrand disease
Hemophilia A
Hemophilia B
Acquired hemophilia
Liver disease associated coagulopathy
Vitamin K deficiency, including warfarin associated coagulopathy
Other anticoagulants
Disseminated intravascular coagulation
  • Excessive fibrinolysis, including antiplasmin deficiency
Clinical presentations
  • Easy bleeding into skin, mucosa, body cavities
  • Presentations associated with organ/tissue dysfunction caused by bleeding
  • Chronic anemia
  • Primary hemostasis disorders: Single site, immediate bleeding after challenge, petechiae
  • Secondary hemostasis disorders: Multiple site, delayed bleeding after challenge, hematoma/hemarthrosis
Key laboratory approaches
  • Platelet count and function tests
  • Coagulation function tests
    • PT and INR (extrinsic pathway)
    • PTT (intrinsic pathway)
    • Coagulation factor test
    • Mild factor deficiencies will not cause prolonged PT or PTT
  • Mixing studies: If PT or PTT are normalized by mixture with normal plasma, factor deficiency is suggested, if not, presence of inhibitor is suggested
General considerations





Practice questions I
Practice questions II
 

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Pathology notes Jun Wang, MD, PhD 1. General information Frequently discussed syndromes Terms of dermatology Terms of hematology 2. Primary immunodeficiency disorders 3. Hemodynamic abnormalities Shock Thrombosis and embolism Bleeding disorders 4.  Benign blood cell disorders Anemia Benign white cell disorders 5. Hematopoietic neoplasms Lymphoid neoplasms Myeloid neoplasms Histiocytic neoplasms: Langerhans cell histiocytosis 6. Cardiovascular system Pulmonary hypertension Cardiovascular system tumors 7. Respiratory tract tumors 8. Gastrointestinal tract Congenital disorders Infectious gastroenteritis Oral cavity Esophagus Stomach Intestinal tumors Salivary glands Exocrine pancreas and gallbladder 9. Urinary system Kidney masses Lower urinary tract 10. Male reproductive system 11. Female genital tract 12. Breast 13. Endocrine organs Pituitary gland Adrenal gland Thyroid gland Parathyroid gland Endocrine pancreas...
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