Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Clinical Pathology > Lecture 7: coagulation I: platelets and primary hemostatics > Flashcards

Lecture 7: coagulation I: platelets and primary hemostatics Flashcards

1
Q

Hemostasis is requires intricate balance between __ and __

A

coagulation and Fibrinolysis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

define coagulation

A

generates thrombin—> converts fibrinogen to fibrin—> clot formation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

define Fibrinolysis

A

degradation of fibrin via plasmin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

what are some causes of hypocoagulation

A

end stage DIC, liver failure (not producing coagulation factors)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

what are some causes of hypercoagulation

A
  1. Severe anemias (IMHA)
  2. Sepsis
  3. Protein losing nephropathy
  4. Endocrine- Cushing, DM
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

describe normal conditions in blood vessels

A

anticoagulable and profibrinolytic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

what are the 4 steps in hemostasis

A
  1. Vasoconstriction
  2. Primary hemostasis- platelets and endothelium
  3. Secondary hemostasis- coagulation cascade
  4. Fibrinolysis/ anti-thrombotic events
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

what are black arrows pointing at

A

platelets

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

describe appearance of platelets

A

anucleate with blue cytoplasm a and reddish cytoplasmic granules

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

what is the equivalent to platelets in non-mammalian species

A

thrombocytes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What indicated by circles

A

black: thrombocytes
red: lymphocytes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

what is platelet structure

A

phospholipid bilayer membrane

Glycoproteins for activation, adhesion and aggregation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

platelets Are produced by __ within the __

A

megakaryocytes within the bone marrow

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

what this and what happening

A

megakaryocyte with budding off bit to form platelet

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

what is platelet circulating lifespan

A

5-9 days

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

platelet production is regulated by __

A

thrombopoietin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

thrombopoietin is produced by __

A

hepatocytes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

thrombopoietin production enhanced by inflammatory cytokine __

A

IL-6

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

what is platelet function

A

Adhesion, activation, aggregation and granule secretion to promote hemostasis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Vascular injury stimulates ___expression on subendothelial cells to initiate coagulation

A

tissue factor

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

what are the steps of primary hemostasis

A
  1. Platelet adhesion
  2. Platelet shape change
  3. Platelet secretion of granules
  4. Platelet aggregation
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What contents are released in platelet granules that promote platelet activation and development

A
  1. ADP
  2. Serotonin
  3. Fibrinogen
  4. Factor V
  5. Factor XI
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

what seen here and what lab work finding would it cause

A

platelet clumping—> pseudo thrombocytopenia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

define thrombocytopenia

A

decreased platelet concentration

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
define thrombocytosis
increased platelet concentration
26
what these
platelet clumps
27
how do you estimate platelet concentration
1. Count number of platelets in ten 100x fields within mono layer 2. Calculate average 3. Multiply average by 15,000 (dogs) or 20,000 (cats)
28
what are the 3 causes of defects in primary hemostasis
1. Thrombocytopenia 2. Thrombopathy 3. Deficiency in VWF
29
what causes thrombopathy
1. defect in glycoprotein (GPIb or GPIIa/IIIb) 2. Abnormal granule function/ release
30
what are some clinical signs of defects in primary hemostasis (thrombocytopenia, thrombopathy, deficient VWF)
1. Petechiae and/or ecchymoses 2. Gingival bleeding 3. Hematuria 4. Melena 5. Epistaxis
31
what wrong and what some ddx
Petechiae, epistaxis Ddx: thrombocytopenia, thrombopathy, deficient WVF
32
what are the 4 main causes of true thrombocytopenia
1. Splenic sequestration 2. Decreased production by bone marrow 3. Increased consumption 4. Increased destruction
33
what are some causes of splenic sequestration leading to thrombocytopenia
1. Marked splenic congestion 2. Heat stroke 3, neoplasia
34
with suspected decreased production of platelets must evaluate __ and find __ to confirm
bone marrow, megakaryocytic hypoplasia
35
with bone marrow panhypoplasia typically see __ before __
leukopenia before thrombocytopenia
36
what are some causes of bone marrow pan hypoplasia
1. Drugs- chemo, estrogen 2. Toxins 3. Radiation
37
dog presents with mucosal petechiae, suspect thrombocytopenia. Do bone marrow biopsy and see following- what wrong/ cause
bone marrow panhyoplasia Cause: decreased production
38
what are some causes of decrease production of platelets leading to thrombocytopenia
1. Myelopthisis: inflammation, neoplasia, myelofibrosis 2. Infectious agents: erhlichiosis, FeLV/FIV, EIA, BVD
39
what can cause increase platelet utilization/consumption leading to thrombocytopenia
trauma, hemorrhage, neoplasia, DIC
40
what is the major cause of thrombocytopenia caused by platelet destruction
immune mediated thrombocytopenia
41
what is primary causes of immune mediated thrombocytopenia
antibodies against platelet antigens
42
what are some secondary causes to Immune mediated thrombocytopenia
lupus, neoplasia, drugs, vaccines (distemper, parvo, panleukopenia)
43
what breeds are predisposed to macrothrombocytopenia
KCCS and akitas
44
what is cause of macrothrombocytopenia
mutation in B1 tubulin gene—> alternates megakaryocyte proplatelet formation and release
45
t or f: dogs with macrothrombocytopenia have no clinical signs or bleeding tendencies
true
46
t or f: total platelet mass (plateletcrit) is normal in dogs with macrothrombocytopenia
true
47
what abnormality is seen on bloodwork in dogs with macrothrombocytopenia
giant platelets (high MPV) with low platelet count
48
from KCCS- what arrow pointing at
macrothrombocytopenia
49
what is platelet count on CBC for thrombocytopathy and deficiency in VWF
normal platelet count on CBC, abnormal function
50
VWF is produced by __ and __
megakaryocytes and endothelial cells
51
VWF is necessary for normal ___
platelet adhesion to collagen
52
What is the most common inherited bleeding disorder in dogs
VWF disease
53
what breed is VWF disease most common in
Doberman pinscher
54
what is cause of type 1 VWF disease
plasma concentrations of all size VWF multimers are <50%
55
what is cause of glanzmann thrombasthenia
deficiency of GPIIb-IIIa: platelets unable to bind fibrinogen—> impaired aggregation and clot formation
56
what are some tests for primary hemostasis disorders
1. CBC- assess platelets 2. Buccal mucosal bleeding time (BMBT) 3. Clot retraction time 4. Platelet function analysis
57
what patients is BMBT contraindicated in and why
thromboccytopenic patients- doesn’t add any additional information (will be prolonged if thrombocytopenic)
58
when in BMBT indicated
normal platelet count with concurrent clinical signs of primary hemostasis disorder
59
what is BMBT results
normal result 2-4 minutes >4 minutes- prolonged
60
what are your ddx for prolonged BMBT
thrombocytopenia, VWD, thrombopathy
61
how do you test for VWD
ELISA- vWF antigen measured by quantitative ELISA with species specific antibodies to vWF
62
platelet function analyzer results are reported as __ in seconds
closure time
63
prolonged closure time from platelet function analyzers indicates what disorders
thrombocytopenia VWD Inherited thrombocytopathies
64
what are some causes for thrombocytosis
1. Physiologic 2. Reactive/inflammatory 3. Recovery from thrombocytopenia 4. Iron deficiency 5. Paraneoplastic 6. Post splenectomy 7. Essential thrombocythemia 8. Megakaryocytic leukemia
65
what is cause of physiologic thrombocytosis
epinephrine induced splenic contraction—> increased number of circulating platelets (mild) Due to excitement/fright
66
what is cause of reactive/inflammatory thrombocytosis
inflammation—> IL-6 stimulates TPO release—> increase platelet production
67
what causes paraneoplastic thrombocytosis
neoplasm producing IL-6–> stimulates TPO release—> increase platelet function
68
What must you evaluate to dx essential thrombocythemia and megakaryocytic leukemia
bone marrow

Clinical Pathology (15 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions