Bleeding disorders

Question 1

In general, mucosal bleeding is suggestive of _____ or a defect in ______ while deep tissue bleeding is suggestive of a defect in _______

Answer 1

mucosal bleeding: thrombocytopenia, defect in platelets or vWF

Deep tissue bleeding: defect in coagulation cascade

Question 2

von Willebrand disease is a _____ or _____ deficiency in vWF, usually with a parallel decrease in factor VIII function

Answer 2

qualitative or quantitative

Question 3

The most common form of vWD is inherited in _______ manner and characterized by a quantitative decrease in vWF

Answer 3

autosomal dominant

Question 4

If there is a significant disparity between vWF antigen and activity, this suggests a _______ defect in vWF

Answer 4

qualitative or functional defect, ie vWF type 2

Question 5

How is type I vWD treated?

Answer 5

DDAVP: stimulates the release of endogenous vWF from endothelial cells

Question 6

_______ contains a large amount of vWF and can be given in sever vWF deficiency

Answer 6

cryoprecipitate

Question 7

Antifibrinolytic agents such as ______ or ____ can be useful for mucocutaneous bleeding in patients with vWD

Answer 7

amicar or tranexamic acid

Question 8

Congenital deficiency of the __________ is known as Glanzmanns thrombasthenia

Answer 8

GpIIb/IIIa complex

characterized by deficient platelet aggregation in response to agonists

Question 9

Congenital deficiency of ______ is known as Bernard-Soulier syndrome

Answer 9

GpIb

results in platelets with defective vWF dependent adhesion, usually mild thrombocytopenia with large circulating platelets

Question 10

List diseases associated with decreased production of platelets

Answer 10

bone marrow disorders ex leukemia
MDS
aplastic anemia
cytotoxic drugs
viral infection
nutritional deficiency
marrow fibrosis

Question 11

List three diseases associated with increased platelet utilization or destruction

Answer 11

immune mediated: ITP

non-immune mediated: DIC, TTP

Question 12

What is the mechanism of ITP?

Answer 12

autoimmune destruction of platelets with normal or increased platelet production

usually antibodies against GpIb or GpIIb/IIIa, leads to platelet destruction in the spleen

Question 13

Distinguish between ITP in children vs adults

Answer 13

In children, usually acute form due to infection and resolves spontaneously

In adults, more likely to be chronic and relapsing

Question 14

In pregnant women with ITP, IgG can cross the placenta and occasionally cause:

Answer 14

neonatal thrombocytopenia

Question 15

What agents are used to treat ITP?

Answer 15

glucocorticoids, IVIG, splenectomy, rituximab

new agents: eltrombopag and romiplostim are TPO agonists, stimulate platelet production

Question 16

What drugs most commonly cause drug induced immune thrombocytopenia

Answer 16

antibiotics, quinine

Question 17

What two conditions are associated with microangiopathic hemolytic anemia?

Answer 17

TTP: deficiency of ADAMTS-13, results in deposition of vWF thrombi in blood vessels leading to microangiopathy

HUS: kidneys are predominant organ affected, shiga toxin triggers endothelial injury leading to microangiopathy

Question 18

_____ and drugs like NSAIDS and aspirin are associated with acquired defects in platelet function

Answer 18

uremia

Question 19

List four causes of thrombocytosis

Answer 19

reactive- infection or trauma
myeloproliferative disorder
post-splenectomy or asplenia
iron deficiency

Question 20

Newborns are vulnerable to bleeding due to _______ deficiency

Answer 20

vitamin K

Question 21

Sever liver disease causes decreased synthesis of fibrinogen, prothrombin, factors _____________. Bleeding can be treated with replacement therapy with ______

Answer 21

Factors V, VII, IX, X, XI

treat with fresh frozen plasma

Question 22

DIC is a syndrome in which ____ and _____ are generated at a rate that exceeds the ability of their natural inhibitors to neutralize them

Answer 22

thrombin (inhibitor is antithrombin)

plasmin (inhibitor is a-2- antiplasmin)

Question 23

DIC is a syndrome that can be associated with:

Answer 23

infection
tumors, esp adenocarcinoma
leukemia
obstetric complications
hemolytic transfusion reactions
liver disease
trauma
shock
surgery

Question 24

DIC involves diffuse endothelial injury. List laboratory findings in DIC

Answer 24

thrombocytopenia
Prolonged PT/INR and aPTT
Elevated FDP and D dimer
Decreased fibrinogen
Red cell fragmentation on blood smear

Question 25

What patients are at risk of spontaneously developing coagulation inhibitors?

Answer 25

Hemophilia- directed against VIII

though autoantibodies can arise without pre-existing coagulation defect