Congenital/Inherited Bleeding Disorders Flashcards
What can the bleeding disorder have an effect on?
Coagulation cascade
Platelets: number and function
Combination of both
Name common bleeding disorders.
Haemophilia A
Haemophilia B/Christmas disease
Von Willebrand’s disease
Thrombophilia
What causes rare congenital bleeding i.e factor 11 deficiency in Ashkenazy Jews (at gene level)?
Autosomal recessive inheritance
Common in cousin marriage
What are inhibitors?
Antibodies that develop against artificial/recombinant factor 8 and 9
Usually disappears quickly after treatment is started.
What must be done to counteract the problem of inhibitors?
Give more recombinant factor (since the immune system will attack some of it)
Just has to be done initially as the immune system stops attacking shortly after treatment starts.
How is haemophilia A inherited?
Sex linked recessive
What cause haemophilia A?
Deficiency in factor 8 (clotting factor)
Who is most affected by haemophilia A?
Males - females are carriers
What is crucial to note about haemophilia?
There is a spectrum of activity.
Could have a small deficiency, a large deficiency or factor 8 could be completely inactive.
How do you treat mild haemophilia A?
DDAVP - drug that releases factor 8 from endothelial cells
Transexamic acid - slows down clot breakdown
How do you treat severe haemophilia A?
Recombinant factor 8
How is haemophilia B inherited?
Sex linked recessive
What causes Haemophilia B?
Deficiency in factor 9 (clotting factor)
Who’s is most affected by haemophilia B?
Males - females carry
What is the treatment for haemophilia B?
Recombinant factor 9
Occasionally transexamic acid can be used.
What is haemophilia?
Tendency to bleed excessively - inability to clot
How is Von Willebrand’s disease inherited?
Autosomal dominant
Who is most affected by VW disease?
Both males and females equally
What causes Von Willebrand’s disease?
Defect in the VW protein attached to platelets and a deficiency in factor 8.
What determines how severe the Von Willebrand’s disease is?
How the gene is inherited
Type 1 = mild : dominant
Type 2 = mild : dominant
Type 3 = severe : recessive
How do you treat Von Willebrand’s disease?
DDAVP - release factor 8 from endothelial cells
very mild cases - tansexamic acid can be used.
In terms of dental treatment; how should a mild/carrier patient be treated?
Shared role between GDP and PDS
Patient must be reviewed every 2 years to ensure there are no changes to their condition.
In terms of dental treatment; how should a patient with a severe bleeding disorder be treated?
Not by a general dentist - treated in hospital
In those with congenital bleeding disorders; For what treatments must special care be taken?
Extractions Some LA: blocks and lingual infiltration Biopsies Periodontal treatment Minor ral surgery
In those with congenital bleeding disorders; what treatments Are Ok To Carry out ?
Prosthodontics
Restorative procedures where safe local anaesthetic is required. (buccal, intraligamentary and intrapapillary infiltrations)
Treatment minus the use of LA
In those with congenital bleeding disorders; What are safe types of injection?
Buccal infiltration
Intraligamentary infiltrations
Intrapapillary infiltrations
In those with congenital bleeding disorders; What are unsafe types of injection?
Inferior alveolar nerve block
Superior posterior alveolar nerve block
lingual infiltration
What post operative measures are taken after an extraction in those with mild congenital bleeding disorders?
observed for 2-3 hours after
Antibiotics may be required
Ensure clear post op instructions are given: patient knows what to do do if the bleeding doesn’t stop/starts again.
How long must patients with severe congenital bleeding disorders be observed for after an extraction?
Overnight in the hospital
List the 3 platelet abnormalities.
Thrombocytopenia: Reduction in platelet numbers.
Qualitative disorder: Correct number of platelets, reduced function.
Thrombocythaemia: increased platelet numbers
*** not related to congenital disorder
What are the ACQUIRED causes Thrombocytopenia?
Can be Idiopathic
Some drugs can cause it;
Alcohol
Heparins
Penicillin
*** not related to congenital disorder
What are the ACQUIRED causes qualitative platelet disorders?
Cirrhosis
drugs
Alcohol
cardiopulmonary bypass
In terms of platelet numbers; treatment is safe to carry out when the number is…?
> 50* 10 (power of) 9
