Duchenne Muscular Dystrophy

Duchenne Muscular Dystrophy or DMD is a genetic disorder and is considered to be the most severe type of muscle dystrophy disease. It is caused by defects in the gene coding for a protein called dystrophin. Lack of the dystrophin protein in muscle cells causes them to be fragile and damages the muscle fibres. Hence Duchenne patients progressively lose their physical functions before they succumb to the disease. Most Duchenne patients are boys and women are generally only the carriers of the mutated gene.

Symptoms of Duchenne muscular dystrophy

The symptoms typically appear before the age of 6. There is gradual decline in muscle strength and by the time they reach the age of 12, most patients use a wheel-chair. DMD is characterized by proximal muscle weakness, muscle loss at the pelvic region, and finally affecting the heart and lung muscles, leading to death. Some of the symptoms that parents start to notice in the children suffering Duchenne Muscular Dystrophy:

• Difficulty in sitting and standing
  
  
• Delayed motor milestones
  
  
• Proximal muscle weakness
  
  
• Frequent falls
  
  
• Difficulty in climbing stairs
  
  
• Difficulty in getting up from sitting to standing position
  
  
• Respiratory and cardiac difficulties in Late teens and early twenties
  
  
• Enlargement of calf muscles due to fat accumulation

Diagnosis and treatment

Initially, a blood test to assess Creatine Kinase is always ordered when Duchenne muscle dystrophy is suspected. Children with DMD always have very high level of creatine kinase (about 10-100 times normal). CK tends to leak out of damaged muscles and therefore leads to elevated blood levels. Once the blood test reveals elevated levels of creative kinase, the condition is confirmed by further tests such as genetic tests or muscle biopsy. Muscle biopsy confirms the absence of dystrophin protein and hence the DMD condition. In addition, structural soft-tissue contracture and spinal deformities may develop due to progressive muscle weakness and imbalance.

As of now, there is no cure for Duchenne Muscular Dystrophy. The condition requires a multi-disciplinary approach in managing the symptoms. Medical care includes Corticosteroid treatment, physiotherapy, rehabilitative interventions, non-invasive ventilatory support, cardiac surveillance and prevention, and Scoliosis correction. These measures are undertaken to enhance the quality of life and longevity of the patient.

Though many improvements are taking place in palliative care, the area of terminal care has not met with much success yet. Duchenne Muscular Dystrophy patients do not normally survive beyond their late twenties. However, research and new approaches such as gene therapy could eventually be used to treat Duchenne Muscular Dystrophy. This therapy aims at correcting genetic mutations that causes the disease.

Becker muscular dystrophy

Becker muscular dystrophy or BMD is one of the nine types of muscular dystrophies characterized by muscle wasting and weakness which is mainly proximal. it is caused by mutations in the same genes as is the case with Duchenne muscular dystrophy. Becker muscular dystrophy is also caused by a mutation of the dystrophin gene, which is responsible for the body to make the protein dystrophin, that is essential for normal muscle function. However, BMD is less severe and is slow in its progression and generally, walking difficulties begin after the age of 16. Becker muscular dystrophy affects only boys and young men, and women are generally only the carriers of the mutated gene.

Symptoms of BMD

Becker muscular dystrophy affects the muscles of the hips, pelvic area, thighs and shoulders, as well as the heart. The symptoms typically start to surface during adolescence and become clearly noticeable by the time the child reaches his mid teens. The health of the patient worsens over time and shortens his life expectancy. The majority of people diagnosed with BMD do not survive beyond 40 or 50 years.

Some of the symptoms include:

• Delay in walking and running for young children
  
  
• Unexplained clumsiness
  
  
• Cramps during exercise
  
  
• Unable to join school sports
  
  
• Weak muscles near torso
  
  
• Enlarged calf muscles
  
  
• Difficulty lifting weights and climbing stairs
  
  
• Falling and finding it hard to get up again
  
  
• Heart problems
  
  
• Complete inability to walk
  
  
• Cardiomyopathy
  

Diagnosis and treatment

The following are some of the diagnostic tests conducted before confirming the Becker muscular atrophy. Serum test for assessing creatine kinase as raised CK levels call for further investigation.

• Genetic analysis to detect abnormal dystrophin gene
  
  
• Muscle biopsy - for dystrophin staining
  
  
• Testing for Cardiomyopathy
  

Treatment of BMD

There is no permanent cure for any muscular dystrophy. Becker muscular dystrophy needs to be managed according to the particular symptoms of each patient. The main aim of the treatment is to optimize the muscle functioning and increase the quality of the life. Physiotherapy, steroid medications, orthopaedic aids such as splints, braces, and genetic counseling go a long way in giving support to the patient.