Tuesday, 3 April 2012


Different strategies of prophylactic treatment for Haemophilia

Haemophilia is an X-linked inherited disorder resulting in a body failure to regulate blood clotting normally due to lack of critical clotting factors (Coppola, Franchini, & Tagliaferri 2009). There are three types of haemophilia: haemophilia A, B and C. About 80 % of haemophilia patients suffer type A haemophilia, which is caused by a lack of clotting factor called factor VIII.  Haemophilia B (deficiency of clotting factor IX), the second most common form of haemophilia, covers up to 20 % of haemophilia cases. The last type is haemophilia C (deficiency of coagulation factor XI), which is very rare and comprises less than 2 % of all haemophilia cases (Coppola, Franchini, & Tagliaferri 2009). Some severe symptoms of haemophilia include deep internal bleeding (e.g. deep-muscle bleeding), joint damage (arthropathy) and intracranial haemorrhage. Prophylactic treatment can be described as a regular therapy by injecting a factor replacement such as recombinant FVIII (for haemophilia A) and recombinant FIX (for haemophilia B) (Coppola, Franchini, & Tagliaferri 2009). Until now, it can be said that prophylactic treatment is the only form of therapy and also the most effective to prevent bleeding (Berntorp, Boulyjenkov, & Brettler 1995).

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In certain countries, the treatment for haemophilia has been done in different methods including the regimen, introduction of treatment, and intensity of treatment (frequency and concentration of the dosage) (Coppola, Franchini, & Tagliaferri 2009).  For example, in Sweden, the introduction of haemophilia treatment is encouraged at 1-2 years of age or earlier before the first or second occurrence of joint bleeds. In addition, recommended dosage of clotting factor replacement including recombinant FVIII and FIX is 20-40 U/kg for at least 3 times per week. The full-dose prophylaxis will be initiated by 2 years of age (Carcao, Chambost, & Ljung 2010).  Meanwhile in Canada, the initiation of therapy is started between 1 and 2.5 years in the context of normal joints. The recommended dosage varies among 50 U/kg (introduction dose) once per week, 30 U/kg twice per week and 25 U/kg (full-dose prophylaxis) three times per week. Furthermore, dosage should be intensified only when unacceptable bleeding has occurred (escalating-dose or tailored prophylaxis). Although the suggested rapid progression of dosage in Sweden showed a good result to avoid arthropathy, it is also associated with some risks such as patient adaptation and high cost (Carcao, Chambost, & Ljung 2010).  The preferable treatment is supposed to be tailored with the patient needs and criteria, which is recommended in Canada. In addition, the Canadian study showed that one-third of haemophilia patients has been successful to retain on once per week dose without any escalating-dose (Biss, Chan, Blanchette et al. 2008)

In conclusion, the different strategies of haemophilia treatment provide an insight about developing a best treatment for haemophilia patients including regimen, frequency of infusion and cost. This strategy is not only to decrease the risk of bleeding, but also most importantly needs to maintain the life quality of the patients.

Reference List:

Berntorp E, Boulyjenkov V, Brettler D, et al. 1995, ‘Modern treatment of haemophilia’, Bull World Health Organ, vol. 73, pp. 691–701. <http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2486807/?tool=pmcentrez&rendertype=abstract>.

Biss TT, Chan AK, Blanchette VS, et al. 2008, ‘The use of prophylaxis in 2663 children and adults with haemophilia: results of the 2006 Canadian national haemophilia prophylaxis survey’, Haemophilia, vol. 14, pp. 923–30.

Carcao M, Chambost H & Ljung R 2010, ‘Devising a best practice approach to prophylaxis in boys with severe haemophilia: evaluation of current treatment strategies’, Haemophilia, vol. 16, pp. 4–9.

Coppola A, Franchini M & Tagliaferri A 2009, ‘Prophylaxis in people with haemophilia’, Thromb Haemost, vol. 101, pp. 674–81. <http://www.schattauer.de.ezproxy.library.uq.edu.au/en/magazine/subject-areas/journals-a-z/thrombosis-and-haemostasis/contents/archive/issue/718/manuscript/11104/show.html>.

Figure 1
< http://www.doctortipster.com/6480-hemophilia-causes-symptoms-diagnosis-and-treatment.html >

Figure 2
< http://www.daviddarling.info/encyclopedia/H/hemophilia.html >

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