Bleeding Disorders

Question 1

two main categories of bleeding disorders (that we have learned)

Answer 1

• defective primary hemostasis
• defective secondary hemostasis

Question 2

categories of defective primary hemostasis

Answer 2

• quantitative platelet deficiency
• qualitative platelet deficiency

Question 3

categories of quantitative platelet deficiency and causes

Answer 3

1. decreased production
   - bone marrow failure (iatrogenic)
   - ineffective hematopoiesis
   - selective impairment of platelet production by drugs, infections, etc.
   - nutritional deficiency (B12, folate)
2. decreased peripheral survival
   - acute idiopathic thrombocytopenic purpura (too few platelets)
   - disease of childhood

Question 4

categories of qualitative platelet deficiencies and causes

Answer 4

• inherited (primary/rare): bernard soulier syndrome, glanzmann thrombasthenia
• acquired (secondary): ingestinon of aspirin and other anti-inflammatory drugs, or from uremia due to accumulation of organic acids in renal failure

Question 5

describe qualitative platelet deficiency

Answer 5

platelets circulate in normal numbers, but are lacking in one or more of the following:
1. adhesion
2. activation
3. release reaction
4. recruitment
5. aggregation
- most commonly recruitment and aggregation

Question 6

categories of defective secondary hemostasis

Answer 6

inherited and acquired cascade factor deficiencies

Question 7

elaborate on inherited cascade factor deficiencies

Answer 7

• inherited (recessive): deficiency disease states have been reported for the following 3 coagulation factors:
  1. factor VIII (hemophilia A)
  2. factor IX (hemophilia B)
  3. factor XI (hemophilia C) - exceedingly rare

Question 8

elaborate on acquired cascade factor deficiencies

Answer 8

• warfarin (coumadin) coagulopathy: warfarin inhibits production of factors II, VII, IX and X by the liver
• heparin coagulopathy: heparin is a potent inhibitor of thrombin

Question 9

glanzmann thrombasthenia

Answer 9

• qualitative platelet deficiency
• autosomal recessive
• platelets fail to aggregate
• due to GbII/IIIa deficiency: this means that platelets cannot bind fibrinogen
• easy bruising and nose bleeds

Question 10

bernard-soulier syndrome

Answer 10

• qualitative platelet deficiency
• giant platelet syndrome
• autosomal recessive
• disorder of GpIb, which is a vWF receptor
• means platelets cannot adhere to subendothelial collagen

Question 11

von Willebrand disease

Answer 11

• most common autosomal dominant disorder/hereditary bleeding disorder
• platelets are normal but defect in vWF
• means that platelets cannot adhere
• often mild and undiagnosed (unidentified vWD is the most common cause underlying hysterectomies that could be prevented)

Question 12

3 main medicines to help stop bleeds

Answer 12

• desmopressin (vasopressin/ADH)
• tranexamic acid
• vWF concentrate
• avoid OTC meds that affect blood clotting!