HAEMOPHILIA A AND B, VON WILLEBRAND’S DISEASE

DESCRIPTION

Haemophilia A, haemophilia B and von Willebrand’s disease are chronic bleeding disorders caused, respectively, by a lack of clotting factor VIII, clotting factor IX and von Willebrand factor (VWF, a carrier protein for factor VIII). Presentation depends on severity of the condition (see classification below). Complications include haemarthrosis with later chronic arthropathy, intracranial haemorrhage, soft

tissue and muscle haematomas. Pain/tingling in a joint suggests bleeding into the joint in a known haemophiliac.

Investigations

Prolonged partial thromboplastin time (PTT).

Factor VIII or factor IX concentration < 25% of normal activity.

Prolonged bleeding time (Von Willebrand’s).

Patient with factor VIII deficiency should be tested annually for factor VIII inhibitor.

GENERAL MEASURES

Haemophilia register.

Ideally, patients should attend a specialised haemophilia centre with a

dedicated multi-disciplinary health care team.

Medic alert bracelet.

Dental care (see below for management of tooth extraction).

Avoid contact sport.

Acute bleeds into joints

Apply ice packs.

Bed rest.

Rest the affected joint/limb until pain free and no further bleeding.

No weight bearing.

Splint (no circumferential casting).

MEDICINE TREATMENT

For mild to moderate pain:

• Paracetamol, oral, 1 g 4–6 hourly when required to a maximum of 4 doses

per 24 hours.

If needed:

ADD

• Tramadol, oral, 50mg, 6 hourly.

For severe pain:

• Morphine, IV, 10 mg 4 hourly.

Exercise great caution when taking blood specimens.

Taking blood from femoral veins is absolutely contra-indicated.

Avoid IM injections.

Avoid aspirin and NSAIDS.

HAEMOPHILIA WITH NO INHIBITORS

The dose of the factor VIII and IX is individualised as it is dependent on body mass, severity of the condition, and the nature and site of the bleeding.

Lyophilised factor VIII concentrate, slow IV infusion.

Required units = body weight (kg) X desired factor increase (%) X 0.5

Dental extraction

Check that inhibitors are absent.

In haemophilia A:

• Lyophilised factor VIII concentrate, IV, 40 units/kg immediately before extraction.

In haemophilia B:

• Lyophilised factor IX concentrate, IV, 40 units/kg immediately before extraction.

• Tranexamic acid, 250 mg dissolved in 10 mL of water.

o Rinse mouth for 2 minutes 6 hourly.

Mucous membrane bleeds

• Tranexamic acid, oral, 1 g 6 hourly.

o Contraindicated in haematuria or in patients with thrombotic tendencies.

In mild von Willebrand’s disease or established responders of mild factor VIII deficiency:

• Desmopressin, IV, 0.3 mcg/kg in at least 30 mL sodium chloride 0.9% administered over 30 minutes.

Emergency treatment while awaiting transfer, if indicated

If serious bleeding with known haemophilia, and no factor VIII available:

• Fresh frozen plasma, IV, 10–20 mL/kg.

HAEMOPHILIA WITH INHIBITORS

Refer for assessment and planning with a haematologist.

• Factor VIII inhibitor-bypassing activity (FEIBA) – under haematologist supervision only.

VON WILLEBRAND’S DISEASE

Mild bleeding

E.g. epistaxis and menorrhagia. Antifibrinolytics, e.g.:

• Tranexamic acid, oral, 1 g 6 hourly.

Recurrent menorrhagia can also be treated effectively with oral contraceptives.

More severe mucous membrane bleeding

For mild von Willebrand’s Disease, which occurs in 80% of patients:

• Desmopressin, IV, 0.3 mcg/kg in at least 30 mL sodium chloride 0.9% administered over 30 minutes.

Note:

Desmopressin is not effective in type 3 and the majority of type 2 von Willebrand’s disease. Intermediate-purity factor VIII concentrates, which contain both von Willebrand factor and factor VIII, may be used for patients with very low von Willebrand factor levels. During surgery or after major trauma, patients should receive:

• Cryoprecipitate, IV, 1 unit/10 kg 12 hourly.

OR

• Lyophilised factor VIII concentrate, IV, 30–50 units/kg/dose given every

12 hours.

o Continue for 48–72 hours to ensure optimal haemostasis.

o For major surgical procedures, use for 7–10 days.

Antifibrinolytic agents may be used in combination with desmospressin or von Willebrand factor containing concentrates (cryoprecipitate or factor VIII) to treat bleeding episodes.

REFERRAL

» All cases with suspected haemophilia (prolonged PTT and normal INR) to a haemophilia treatment centre, for assessment, genetic counselling and planning of management.

» Patients with proven antibodies against factor VIII.

» For further replacement, complex situations and complications in consultation with a haematologist.

Reference and further reading

Standard Treatment Guidelines and Essential Medicines List for South Africa 2012 Edition