Stressing the urgent need for awareness, Prof Johnny Mahlangu recently spoke to Medical Chronicle about haemophilia. One of the main concerns about the bleeding disorder is the low diagnosis thereof. “The current SA population is just over 57 million,” said Prof Mahlangu.
“We expect there to be about 5.7 million people with haemophilia, however only 2.3 million have been diagnosed. So, we’ve only identified 40% of the potential total population of people with haemophilia (PWH). Worldwide statistics are equally concerning. “Globally we expect 770 000 of the 7.7 billion population have haemophilia, however to date only 200 000 have been identified. Furthermore, of the 200 000 people who have been identified, 70% of them don’t have access to treatment.”
An inherited bleeding disorder affecting males, haemophilia is caused by mutation in the clotting factor gene. “This mutation is inherited in an X-linked fashion where it is carried by females and affecting males. Up to 30% of people with haemophilia do not have a family history but have the mutation which happens spontaneously. “Affecting all races, haemophilia A occurs in about one of every 5 000 male births, while haemophilia B occurs in approximately one of every 25 000 male births,” said Prof Mahlangu.
“In almost all instances females are the carriers, while the males are affected by haemophilia. However, this does not mean females can’t have haemophilia. We have instances where they are symptomatic and bleed in the same way as males with haemophilia.”
Blood contains many proteins called clotting factors that can help to stop bleeding. People with haemophilia have low levels of either factor VIII (8) or factor IX (9). The severity of haemophilia that a person has is determined by the amount of factor in the blood. The lower the amount of the factor, the more likely it is that bleeding will occur, which can lead to serious health problems.
ADVANCES IN CARE AND EMERGING TREATMENT OPTIONS
Treatment is vital to help reduce the pain, crippling, suffering, and even premature death, of those living with a bleeding disorder. Although a cure has yet to be developed, treatment for haemophilia is very effective. “Replacement therapy is the standard of care,” said Prof Mahlangu.
“To date several gene therapy development programmes for both haemophilia A and B are evolving. All these programmes use hepatotropic adeno-associated viral (AAV) vectors, to deliver the transgene in the liver, which is then able to produce the missing clotting protein. The results of both FVIII and FIX gene therapy to date have been very encouraging with many patients successfully converting from severe (<1% clotting factor level) to moderate or mild phenotypes (2-50% clotting factor levels),” he said.
“Whilst the safety profile of gene therapy in adults has been acceptable so far, unexpected transaminitis has been observed in a number of study participants. To date gene therapy represent a dichotomy of knowns and unknowns. It is a matter of time before some of the unknowns are clearer.”
Gene therapy remains an exciting possibility and holds out the prospect of a partial or complete cure. There are many technical obstacles to overcome, but research currently under way is encouraging. Once diagnosed, Prof Mahlangu stresses the importance for doctors to advise patients to always treat bleeds early. “If in doubt, treat with the missing factor, comply with treatment regimen, and visit the haemophilia treatment centre regularly for optimal management.”
TOP 5 THINGS ALL DOCTORS SHOULD KNOW ABOUT HAEMOPHILIA
- Haemophilia is an inherited bleeding disorder in which patients can bleed anywhere but commonly into joints
- Haemophilia affects males, females are carriers
- Currently, haemophilia can be managed but not cured
- People with haemophilia can live a relatively normal life
- Contact your haemophilia experts for the most up to date management of haemophilia.