Spotlight on Duchenne Muscular Dystrophy; by Tetyana Pravytska

Duchenne muscular dystrophy(DMD) is a rare and inhereted genetic condition . It affects as many as one in 3500 boys. In 1986, researchers discovered the faulty gene on the X-chromosome ( sex -linked chromosome), which is responsible for DMD . As a female has two X chromosomes in her cells , she usually does not display abnormality. In contrast , a male has only one X-chromosome. Thus, he has a 50 per cent chance of being affected if his mother carries this gene. Once the gene is invalid, it does not produce a specific protein called dystrophin. If the skeletal muscles lack of dystrophin, they become easily injured and eventually die. It causes gradual muscle weakness .

One of the main concerns is child’s motor development. Week muscles make affected boys walk late (at 18 months of age or later). There are usually problems in rising up from the floor, climbing stairs, running and hopping . Despite gradual worsening of muscle function, some boys have apparent improvement between the ages of 5 and 8. As the disease progresses and the boy reaches 12 years, he may begin to use a wheelchair for a wide level of support. When the boy is confined to a wheelchair, he may gradually develop skeletal deformities, heart and respiratory problems.

In addition , the boy might experience fatigue after even mild exercise. Some of the boys might have autism or attention -deficit hyperactivity disorder, while others might develop depression or anxiety.

So,one of the questions that parents will probably ask – how can we prolong child’s independent walking?

The most recent recommendations came from international experts – the DMD Care Considerations Working Group. They recommend that a child with DMD should be under the care of a wide range of specialists – a children’s neurologist,, neurogeneticist, children’s orthopaedist, rehabilitation specialists, children’s doctor, or family doctor.

As for medication, glucocorticoids still remains treatment of choice for improving muscle function in DMD. Taking it regularly gives not only short-term benefits but also prolongs a child’s independent walking skills. There is some evidence that glucocoticoids make heart function better. The dark side of this medication is side-effects. Therefore, a steroid card is helpful to alert a doctor in case of an emergency – fracture, serious infection, need for surgery, or general anaesthesia.

The decision of starting this medication rests on individual factors. But in all cases, the child is offered childhood immunisation to give protection from infections as early as possible. Above all, the child should have immunity against chickenpox. This infection can be very serious in children who are on steroids.

Physical exercise is always important. An appropriate exercise programme should be started as early as possible. With the support of physiotherapy, regular and moderate exercise is beneficial for the strengthening of weak muscles. It prevents muscle wasting and is gentle enough for damaged muscles. If the exercise causes pain, the activity needs to be reduced and monitored for myoglobinuria.

Along with exercise, staying social is an additional benefit for the well-being of children. Unsurprisingly, children with DMD have difficulty to be socially active when they age. A recent study, conducted by the Department of Occupational Therapy, University of Pittsburgh, the USA, confirmed that older boys are less likely to take part in social and physical activities. They recommended to encourage boys to continue to participate in activities outside of the home. If someone is wheelchair-bound, that’s not a barrier to participate in recreational activities. The possibilities are endless – just leave it up to your imaginations.

Today, researches are developing new and promising treatments for DMD. Hope for the future is in gene therapy. Significant progress has been done so far on animals. Relying on encouraging preclinical results, researchers have started human trials. Some studies are under-way. They look at safe and efficient way of transferring the gene, which produces dystrophin to make muscles stronger. Stem cells therapy is also seen as the future treatment for this medical condition. Stem cells are known for their self renewal capacity. Invaluable work has been done to use its potential for regeneration of affected muscles. So, when these new advances become fully tested for safety and efficacy, they will reach clinic, and children with DMD will be successfully treated.