Congenital Bleeding Disorders (Ma. Ysabel Lesaca-Medina, MD) Flashcards
(93 cards)
1
Q
Phases of hemostasis
A
Vascular phases Platelet phase Coagulation phase Clot retraction Clot destruction
2
Q
Automatic response of vessel to contain bleeding to site of injury
A
Transient vasoconstriction (reflex neurogenic and endothelin secretion)
3
Q
Three As of the platelet phase
A
Adhesion
Activation
Aggregation
4
Q
Platelet activators
A
ADP
Epinephrine
5
Q
Serves as bridge in the aggregation of platelets
A
Fibrinogen
6
Q
Goal of coagulation phase of hemostasis
A
Fibrin thombus formation (for stability)
7
Q
Factors that play a role in clot destruction
A
Thrombin Factor XII (Hageman)
8
Q
How is the intrinsic pathway activated?
A
Release of kininogens/kallikrein from injured surface
9
Q
Pathway measured by PTT
A
Intrinsic pathway
Brad P(I)TT has a P(E)T!
10
Q
What does automated PTT measure?
A
Factor XII
11
Q
Trace the intrinsic pathway
A
XII -> XI -> IX + VIIIa -> X -> Common Pathway
12
Q
Durations of intrinsic and extrinsic pathways
A
Intrinsic pathway: 20 – 30 seconds
Extrinsic pathway: 10 – 12 seconds
13
Q
How is the extrinsic pathway activated?
A
Trauma
14
Q
Trace the extrinsic pathway
A
Factor VII + Tissue Factor -> X -> Common pathway
15
Q
Pathway measured by PT
A
Extrinsic pathway
Brad P(I)TT has a P(E)T!
16
Q
Describe: Prothrombin Time
A
Time for III and CaCl to form a clot
17
Q
Trace the common pathway
A
X -> Prothrombin to Thrombin -> Fibrinogen to Fibrin + Factor XIIIa -> Fibrin clot
18
Q
Pathway measured by TT
A
Common pathway
19
Q
How does deficiency in Factor XIII manifest
A
Normal hemostasis but persistent bleeding
20
Q
Used to measure Factor XIII
A
Urea Clot Lysis Assay
21
Q
Vitamin K-dependent factors
A
IX, X, VII and II (1972)
22
Q
T/F: Factor VI has the shortest half-life at 8 hours
A
False
Factor VII. Factor VI does not exist.
23
Q
First factor to get depleted
A
Factor VII
24
Q
T/F: In acute Vit. K deficiency, only Factor VII decreases
A
True
25
T/F: Mucosal bleeding points to a coagulation problem.
False
It points to a platelet problem.
26
T/F: Deep tissue bleeding points to a coagulation problem.
True
27
When is there delayed onset bleeding?
Factor XIII deficiency
28
Liver disease affects the production of all clotting factors except these.
Factor VIII
| vWF
29
T/F: A person with liver disease is more prone to thrombosis and exhibits a longer PT.
True
30
Given to the patient if vitamin K does not correct the PT.
Fresh frozen plasma
31
Examples of antiplatelet drugs
Aspirin
| NSAIDs
32
Examples of anticoagulants
Heparin
Coumadin
Warfarin (combats vit. K)
33
Examples of antibiotics that can disrupt vit. K synthesis
Penicillin
Cephalosporin
Amphotericin
34
Useful in ruling in congenital bleeding disorders
Consanguinity
35
Criteria for menorrhagia
> 3 pads/day
Flooding
Hb < 10g/L
36
Common manifestation of hemophilia
Hemarthrosis
37
Indicative of a coagulation problem
Hemarthrosis
| Intramuscular bleeds
38
Differentiate petechiae, purpura and ecchymoses on the basis of size
Petechiae - < 2 mm
Purpura - 2 mm to 1 cm
Ecchymoses - > 1 cm
39
Used to check the status of fibrinogen
Thrombin time
40
Blood is passed into a machine and the time it takes to measure hole closure corresponds to "bleeding time"
Platelet Function Analyzer (PFA)
41
Used to determine whether a patient has factor deficiency or antibodies against clotting factors
Mixing studies
42
T/F: If mixing patient blood with normal blood solves the problem, patient has antibody inhibitors in the blood.
False
Patient has factor deficiency.
43
Finding if clot lyses quickly in urea clot lysis assay
Factor XIII deficiency
44
Differentials if PT is elevated while PTT and platelet levels are normal
Early liver disease
Early Vit. K deficiency
Factor VII deficiency
45
Differentials if PTT is elevated while PT and platelet levels are normal
Factor VIII deficiency (hemophilia or vWD)
Factor IX, XI or XII deficiency
Inhibitors
46
Differentials if both PTT and PT are elevated and platelet levels are normal
Late liver disease
Late Vit. K deficiency
Massive transfusion
47
Differentials if PTT and TT are elevated and platelet and PT levels are normal
Heparin
48
Differentials if PTT, TT, PT and platelet levels are all normal
```
vWD
Platelet function disorder
Mild factor deficiency (VIII, IX, XI or XIII)
Collagen disorder
Vit. C deficiency
```
49
Differentials if platelet levels are decreased
CAMT, TAR, BSS, WAS, GPOS or ITP
| Infection
50
Most common inherited bleeding disorder
Von Willebrand's disease
51
Rare bleeding disorder where there is no megakaryocyte in the bone marrow
Congenital Amegakaryocytic Thrombocytopenia (CAMT)
52
Rare bleeding disorder where alpha-granules are lacking and patient is prone to infection
Gray Platelet Syndrome (GPS)
53
Rare bleeding disorder involving multiple congenital anomalies and thrombocytopenia
Thrombocytopenia with Absent Radius (TAR)
54
Rare bleeding disorder where platelets are small
Wiskott Aldrich Syndrome (WAS)
55
Most common severe congenital bleeding disorder
Hemophilia
56
Severity classifications for hemophilia
Severe - <1% activity
Moderate - 1 - 5% activity
Mild - 5 - 50% activity
57
Types of hemophilia
Hemophilia A - FVIII
| Hemophilia B - FIX
58
Characteristics of hemophilia carriers
Factor VIII usually below normal levels
Mild bruising
Heavy menstrual periods
59
Complications of hemophilia
Hemarthroses
Intracranial hemorrhage
Intramuscular hematomas
60
Common sites of intramuscular hematomas
Anterior forearm
| Anterior tibial compartments
61
General aim of hemophilia management
Correct FVIII to normal limits
62
Synthetic vasopressin analog that causes transient rise in FVIII and vWF and used for mild cases of hemophilia
Desmopressin or DDAVP
63
Used to treat moderate to severe hemophilia B
Fresh frozen plasma or cryosupernate (if available)
64
Used to treat moderate to severe hemophilia A in the absence of FVIII
Cryoprecipitate
65
Not used in treatment of hemophilic patients < 6 months old due to increased risk of inhibitor development
Preventive Factor VIII infusions
66
Quantifies inhibitor formation
Bethesda units (BU)
67
Define: 1 Bethesda unit (1 BU)
Amount of antibodyt hat neutralizes 50% of FVIII or IX present after 2 hours incubation at 37 degrees Celsius
68
Treatment for inhibitor patients with BU < 5
Increase dose of FVIII
69
Treatment for inhibitor patients with BU > 5
Bypass agents
Prothrombin complex concentrates
Immune tolerance induction
Immunosuppressive agents (rituximab)
70
Methods of immune tolerance induction (ITI)
Malmo Regimen
Van Cremeld Regimen
Bonn Regimen
71
Infectious diseases hemophilic patients are still at risk for during treatment
Hepatitis A
Creutzfeld-Jakob Disease
Parvovirus B19
72
Complication of gene transfer treatment of hemophilia
Hepatitis with concomitant destruction of transferred gene
73
Types of Von Willebrand's Disease (vWD)
Type 1 - Classic partial quantitative deficiency
Type 2 - Qualitative deficiency
Type 3 - Near complete deficiency
74
Mode of inheritance of Von Willebrand's Disease (vWD)
Autosomal dominant (mostly), but can be autosomal recessive
75
Most common cause of acquired vWD
Presence of antibody to vWF
76
T/F: Theoretically, there should be equal cases of vWD in both sexes
True
77
T/F: Sometimes, PTT is elevated in Type 2 vWD
False
Type 3 vWD
78
T/F: Platelet count may be decreased in vWD Types 2 and 3.
True
79
T/F: Blood type O has lower levels of vWF
True
80
Used for definitive testing of vWD
vWF assay
81
Treatment of vWD
Desmopressin (types 1 & 2)
82
Mode of inheritance of rare congenital coagulation factor deficiencies
Autosomal recessive
83
Congenital coagulation factor deficiency that causes the most bleeding
Factor X deficiency
| Factor XIII deficiency
84
SSx of rare coagulation disorders
```
Umbilical stump bleeding
Delayed cord separation
Intracranial or intestinal hemorrhage
Muscle hematomas
Easy bruising
Prolonged bleeding following prick
```
85
Disorder characterized by absence of GPIb/IX receptor
Bernard-Soulier Syndrome (BSS)
86
Mode of inheritance of Wiskott-Aldrich Syndrome
X-linked
87
Mode of inheritance of Gray Platelet Syndrome
Autosomal dominant or recessive
88
Mode of inheritance of Bernard-Soulier Syndrome
Autosomal recessive
89
Disorder characterized by defective GP IIb/IIIa interaction
Glanzmann Thrombasthenia (GT)
90
How much Factor VIII should be infused in non-life threatening bleeds?
25 - 40 U/kg
91
How much Factor VIII should be infused in life-threatening bleeds?
50 U/kg
92
T/F: vW antigen levels are normal in Type II vWD
True
93
Characteristics of Factor VII responsible for isolated prolonged PT in early liver disease or Vitamin K deficiency
Short half-life
