Bleeding Disorders

Question 1

Some bleeding disorders are caused by platelets would be…

Answer 1

Thrombocytopenia and platelet dysfunction

Question 2

Some bleeding disorders caused by cloting wolud be….

Answer 2

Vitamine K deficiency, hemophilia, von Willebrand syndrome, liver disease

Question 3

Some bleeding disorders caused by blood vessel integrity would be…

Answer 3

Vitamin C deficiency - makes collagen not work and then arterial walls get weaker. Cushing Syndrome - cortisol causes decreased vessel wall integrity

Question 4

What signs and symptoms would exist with someone with a bleeding disorder?

Answer 4

Bleeding gums, nosebleeds, petechiae, purpura, echymoses, easy bruising, prolonged bleeding following trauma, surgery, and dental work. Blood in stools and urine, bleeding into a joint (hemarthrosis), excessive menstrual bleeding (menorrhagia)

Question 5

What’s another word for platelets?

Answer 5

Thrombocytes. They hang out in the spleen and also removed by the spleen after 8 to 12 days.

Question 6

Where do thrombocytes come from?

Answer 6

They develop from megakaryocytes in the bone marrow. They break apart into fragments which become platelets. One megakaryocyte makes 1000’s of platelets.

Question 7

What hormone stimulates thrombopoiesis?

Answer 7

Thrombopoietin - which is in the liver, kidney, smooth muscle and bone marrow.

Question 8

Does thrombocytopenia affect clotting?

Answer 8

No, it just affects how the platelet plug is formed because there’s just not enough platelets.

Question 9

Does thrombocytopenia affect big vessels much?

Answer 9

No, it affects smaller blood vessels like the skin or mucous membranes of the mouth, nose, gi tract, and uterus.

Question 10

What is the etiology of thrombocytopenia?

Answer 10

1) Decreased platelet production
2) Increased platelet destruction
3) Increased sequestration by the spleen

Question 11

What would cause decreased platelet production?

Answer 11

1) Folate and vitamine b12 deficiency
2) aplastic anemia (idiopathic or chemo)
3) Radiation therapy or chemo
4) Leukemia (crowding of bone marrow by malignant cells)
5) Infections (HIV, cytomegalovirus)

Question 12

What would cause increased platelet destruction?

Answer 12

1) Drug induced thrombocytopenia (heparin)
2) Immune Thrombocytopenia purpura (ITP) (antibodies target platelets)
3) Autoimmune disorders (Lupus)
4) Mechanical injury (heart valves, malignant hypertension)

Question 13

What would cause splenic sequestration (pooling) of platelets?

Answer 13

1) Splenomegaly (from portal htn, or liver or heart failure) The spleen becomes overactive and destroys platelets and WBC’s
2) Hypothermia

Question 14

Does whole blood have platelets?

Answer 14

No

Question 15

In Heparin induced thrombocytopenia, what do antibodies bind onto?

Answer 15

They bind onto heparin-platelet factor 4 (PF-4) complexes. PF-4 is released from platelets and bind to heparin and then 10% people develop antibodies against this complex.

Question 16

What happens when antibodies bind to PF-4?

Answer 16

1) Platelets are targeted for destruction in the spleen - Transient thrombocytopenia
2) Platelets get activated causing increased risk of thrombosis.

Question 17

What autoimmune disorder can cause platelets to be destroyed by macrophages in the spleen?

Answer 17

Immune Thrombocytopenia Purpura (ITP). In this illness, autoantibodies against platelet glycoproteins target platelets for destruction by macrophages in the spleen. This also triggers MAC.

Question 18

ITP can be classified as Primary or Secondary. Explain the difference.

Answer 18

1) Primary or secondary. Primary is idiopathic. Secondary is due to AIDS, lupus, antiphospholipid syndrome, certain drugs.

Question 19

ITP can also be classified as acute or chronic. Explain the difference.

Answer 19

ITP that’s acute is less than 6 months. Chronic ITP is > 12 months. The in between part is called “persistent” - 6 months to 1 year.

Question 20

Childhood (acute) ITP can happen after viral infections and certain vaccinations. What common vaccination can trigger this issue?

Answer 20

MMR. People usually get better after 2 weeks - 6 months when the infection is cleared.

Question 21

What age group is commonly affected by childhood ITP?

Answer 21

5 years old.

Question 22

What are the symptoms of childhood ITP?

Answer 22

Petechiae and purpura.

Question 23

What age group commonly gets adult ITP?

Answer 23

18 years old to 40 years old.

Question 24

Who’s more likely to get ITP? A man or a woman?

Answer 24

A woman

Question 25

Why is the spleen enlarged in immune thrombocytopenia purpura?

Answer 25

Spleen is more active and there’s more macrophages in the spleen.

Question 26

Would your PTT be affected by thrombocytopenia?

Answer 26

No. Ptt measures clotting. Not platelet plugs.

Question 27

What lab value would be decreased in thrombocytopenia?

Answer 27

Platelet count would be decreased.

Question 28

How do we fix chronic ITP?

Answer 28

1) Immunoglobulin infusion. Doesn’t work that well though because the effects are short lived and very expensive.
2) If it’s mild, just monitor platelet count
3) Initially give corticosteroids/ immune suppresants
4) Thrombopoietin receptor agonist (new drug)
5) Surgery to remove spleen.
6) Correct the underlying cause!

Question 29

Would a platelet transfusion be helpful for someone with ITP?

Answer 29

Likely not because the body will continue to make antibodies that would destroy the platelets.

Question 30

What sort of ITP patient could receive a platelet transfusion?

Answer 30

Someone with drug induced, or chemo aplastic anemia/ someone who has trouble making platelets could get blood transfusion.

Question 31

What foods have vitamin K?

Answer 31

Cabbage, cauliflower, spinach, greens, leafy vegetables, and cereals, liver, spinach, broccoli, grains.

Question 32

Where is vitamin K synthesized?

Answer 32

In the large intestine. Made by bacteria.

Question 33

Why is vitamin K important?

Answer 33

Helpful in making certain clotting factors. (II, VII, IX, X)

Question 34

Vitamin K needs what element in order to form the clot?

Answer 34

Calcium. It brides the binding of “gla residues” of clotting factors to the platelet surface. This accelerates and localizes the synthesis of certain clotting factors.

Question 35

What conditions cause a vitamin K deficiency?

Answer 35

1) Liver failure - liver can’t store vitamin K. Can’t make bile needed for digestion and absorption.
2) newborn - not a lot of vitamin K in breast milk and can’t metabolize it. Also not a lot of bacteria in their large intestine
4) Prolonged antibiotics
4) CF, and celiac disease

Question 36

How does warfarin work?

Answer 36

Decreases prothrombin levels and other clotting factors. Alters Vitamin K which reduces it’s ability to participate in synthesis of vitamin K dependent coagulation factors in the liver.