inherited blood disorders

Question 1

what is an inherited bleeding disorder?

Answer 1

an acquired defect which affects the coagulation of the blood

Question 2

what can inherited bleeding disorders affect?

Answer 2

coagulation cascade
-reduction in coagulation factors/control problems
platelets
-number/function
a combined deficiency

Question 3

what is haemophilia?

Answer 3

too little clot formed

Question 4

what is thrombophilia?

Answer 4

too much clot formed

Question 5

what disorders reduce coagulation factors?

Answer 5

factor VII deficiency
-haemophilia/haemophilia A
factor IX deficiency
-xmas disease/haemophilia B
von Willlebrand's disease
-reduced factor VIII level
-reduced platelet aggregation
factor XI deficiency

Question 6

describe the inheritance of haemophilia A & B

Answer 6

sex-linked recessive
defective gene on the X chromosome
males affected
females carrier

Question 7

what does the severity of haemophilia A & B depend on?

Answer 7

amount of factor produced, 1iu is normal
severe <0.01iu
moderate -0.02-0.09iu
mild 0.1-0.4iu
carrier <0.5iu

Question 8

how is mild and carrier haemophilia A managed?

Answer 8

DDAVP

very mild only require oral tranexamic acid

Question 9

how is severe and moderate haemophilia A managed?

Answer 9

recombinant factor VII

-produced in lab

Question 10

what is DDAVP

Answer 10

releases factor VIII that has been bound to endothelial cells giving temporary boost to factor level and clotting ability

Question 11

what is tranexamic acid?

Answer 11

inhibitor of fibrinolysis-keeps any clot formed

Question 12

how is mild and carrier haemophilia B managed?

Answer 12

recombinant factor IX

Question 13

how is severe and moderate haemophilia B managed?

Answer 13

recombinant factor IX

Question 14

what are coagulation factor inhibitors?

Answer 14

antibodies which develop factor VIII & IX

Question 15

describe the reaction to coagulation factor inhibitors

Answer 15

amount of antibody developed varies between px
high levels more frequent factors given
peak then settles
2nd dose larger to overcome inhibitors produced in first dose
some develop inhibitor when first start tx

Question 16

describe von Willebrand’s disease

Answer 16

autosomal dominant 
(not X chromosome)
both sexes equal
deficiency in von willebrands factor
reduction in factor VIIi levels
defective vW factor on platelets interacts badly with factor VIII so poor clot activation by platelets

Question 17

what are the types of von Willebrand’s?

Answer 17

1- dominant mild
2- dominant mild
3- recessive severe

Question 18

how is severe von Willebrand’s treated

Answer 18

DDAVP

Question 19

how is mild and carrier von Willebrand’s treated?

Answer 19

oral tranexamic acid

Question 20

how do rarer bleeding disorders occur?

Answer 20

inherited defects of other factors in the coagulation pathway
inherited defect of either the number or function of the platalets

Question 21

how should you manage dental px with bleeding disorders?

Answer 21

vary depending on likelihood of bleeding
-non-bleeding procedures in primary care
bleeding risk depends on baseline factor activity
-higher=lower risk

Question 22

how is dental care given to mild/carrier hameophiliacs?

Answer 22

shared by GDP/PDS depending on procedure/LA needs

px reviewed at haemophilia centre dental unit every 2 years

Question 23

how is dental care given to severe/moderate haemophiliacs

Answer 23

dental unit in haemophilia centre

no-risk treatments in primary care

Question 24

what are bleeding risk procedures?

Answer 24

LA
extractions
minor oral surgery
perio surgery
biopsies

Question 25

what LA is safe?

Answer 25

buccal infiltration
intraligamentary
intra-papillary

Question 26

what are dangerous LA?

Answer 26

IDB
lingual infiltration
posterior superior nerve block

Question 27

how should severe/moderate px be observed after extraction/surgery?

Answer 27

overnight

Question 28

how should mild/carrier px be observed after extraction/surgery?

Answer 28

for 2-3 hours

Question 29

how is prevention given?

Answer 29

dietary advice
oral hygiene
fluoride supplements
regular dental care
fissure sealant- even adult

Question 30

what is thrombophilia?

Answer 30

increased risk of clots forming
-formation greater than breakdown ability
-formed inappropriately in circulation
often acquired with genetic tendency
if clot emobilises can become major blockage

Question 31

describe inherited hypercoagulation

Answer 31

protein C deficiency
protein s deficiency
factor V leiden
antithromib III deficiency

Question 32

describe acquired hypercoagulation

Answer 32

antiphospholipid syndrome
oral contraceptives
surgery
trauma
cancer
pregnancy
immobilisation

Question 33

what is thrombocytopenia?

Answer 33

reduced platelet numbers

Question 34

what are qualitative disorders?

Answer 34

normal platelet number but abnormal function

Question 35

what is thrombocythemia?

Answer 35

increased platelet numbers

Question 36

what can cause thrombocytopenia?

Answer 36

idiopathic
drug related
-alcohol
-penicillin based drugs
-heparin
secondary to lymphoproliferative disorder eg leukemia

Question 37

when can dental tx safely proceed in thrombocytopenia?

Answer 37

100x10^9 primary care

50x10^9 hospital

Question 38

how can qualitative platelet disorders be acquired?

Answer 38

cirrhosis
drugs
alcohol
cardiopulmonary bypass

Question 39

what causes inherited qualitative platelet disorders?

Answer 39

bernard soulier syndrome
hermansky pudlak
glanzmann’s thrombasthenia

Question 40

what are safe procedures for pz with platelet disorders?

Answer 40

hygiene therapy
removable pros
rest. dentistry
endodontics
ortho
only when platelet count > 100x10^9/L

Question 41

what procedures is special care required for platelet disorder px?

Answer 41

extractions
minor oral surgery
perio surgery
biopsies

Question 42

describe the platelet count for each dental care setting for px with platelet disorders

Answer 42

below 100x10^9 primary care
below 50x10^9 hospital
above500x10^9 either