Monday, May 30, 2011

Muscular dystrophy - Diagnosis

The first step in diagnosis is to the patient's physical examinationto highlight the characteristic signs of muscular dystrophy.

Laboratory analysis consists in the concentration of creatineresearch, a chemical released in the process of necrosis(destruction) of cells. An increased concentration of creatine allowsdiagnosis of muscular dystrophy.

For diagnosis of Duchenne myopathy may be investigated and the level of dystrophin in muscle. A very low level of this protein willindicate the presence of DMD.

Muscle biopsy is the best method of diagnosis. During thismedical procedure, is take a sample of tissue for examinationunder a microscope. In the case of muscular dystrophy, willhighlight microscopic muscle fiber degeneration. As the disease,muscle tissue necrosis (dead) will be replaced by connectivetissue or fat.

Muscle functioning can be verified with electromyography (EMG) -test that measures electrical activity of muscles.

Muscular dystrophy - Signs and symptoms

Generally, symptoms occur before age 5.
Children who suffer from muscular dystrophy have trouble walking, climbing stairs, lifting arms overhead or lifting from the ground.Normally, muscle atrophy affects basin first, then reaches shoulder muscles. As the weakening of the muscles, they grow in size by replacing fat with muscle fibers (pseudohipertrofie).
In some forms of muscular dystrophy, the disease becomes debilitating in adolescence, the patient was immobilized in a wheelchair. Note the changes of the spine (scoliosis). Pneumonia and other respiratory diseases are common due to malfunctioning of the respiratory muscles.
General symptoms and signs of muscular dystrophies are:

 
- Muscle weakness
 
- Coordination slips
 
- Progressive sinvaliditate
Signs and symptoms vary depending on the specific type of muscular dystrophy in question. Each type differs in terms of onset, muscle groups affected and the disease.
Duchenne muscular dystrophy: the onset of symptoms generally occurs between 3 and 5 years. As a result of lower limb muscle atrophy, children have a tendency of falling and difficulty in lifting off the ground. As weight loss, muscle fibers grow in size due to the replacement of muscle tissue or fat necrosis (pseudohipertrofie).Using a wheelchair becomes necessary to 12 years. Some patients have scoliosis, mental retardation or suffer from heart failure.
Becker muscular dystrophy - the symptoms are comparable with those of Duchenne myopathy, but begins between 5 and 15 years are less marked.
Myotonic dystrophy - myotonic characterized by (abnormally prolonged muscle contractions difficulties in decontractare).Debuts at five years, affecting mainly the hands and tongue. Facial muscles may also be affected, and neck muscles, toes and ankle.Atrophy of the muscles involved in speech and swallowing difficulties in performing these acts trains. Impaired diaphragm cause breathing difficulties.
Muscular dystrophy belt - symptoms begins in late childhood or early adulthood. It is characterized by muscle atrophy in shoulders and hips, and breathing difficulties in case of reaching the diaphragm. It may be accompanied by heart failure or arrhythmia.
Facio-scapular-humeral dystrophy or (Landouzy-Dejerine dystrophy) - is characterized by affecting the facial muscles, so patients can not smile, whistle, or close your eyes.

Emery-Dreifuss muscular dystrophy

Emery-Dreifuss muscular dystrophy is a disease transmitted byautosomal dominant, recessive (rarely) or X-linked. The incidenceis not known. Women can be carriers, but only men can beaffected with the clinical forms of X-linked transmission. GeneEmery-Dreifuss dystrophy involved in coding for a protein callednuclear membranes emerina.

Amyotrophy (muscle atrophy) and weakness may occur before the age of 20 years, usually affecting the arm muscles (biceps, triceps)and more rarely, the muscles of the legs. Emery-Dreifuss dystrophycan affect the heart, involving paralysis fibrillation, conduction abnormalities (atrioventricular block), cardiomyopathy (damage toheart muscle) and an increased risk of sudden death.

Diagnosis is based on clinical data, age of onset, family historyand are supported by the slight increase in the level of serumcreatinine by electromyography and muscle biopsy. DNA testsconfirm the diagnosis.

Treatment aims to prevent contractures. Using a pacemaker(pacemaker) is indicated in patients with conduction disturbances(AV block).

Muscular dystrophy belt

Muscular dystrophy belt comprises a group of diseases that affectmuscles and pelvic girdle (shoulder and hip muscles). The diseasecan then reach the limb muscles, but its evolution is slow.

The disease is autosomal recessive nature (rarely dominant) and therefore affects both sexes equally and usually begins inadolescence or at age 20 -30 years. In autosomal recessivecases, symptoms tend to settle in childhood. Intellectualcapabilities are not affected.

Treatment focuses on preventing contractures.

Muscular dystrophy - Duchenne muscular dystrophy

Duchenne muscular dystrophy (DMD) is the most common form ofmuscular dystrophy, affecting about three boys in 1000. It is ahereditary disease with autosomal recessive transmission linkedto chromosome X. Therefore, Duchenne myopathy affects onlymale infants.

The disease is caused by a faulty gene which causes deficiency of a protein called dystrophin. The absence of dystrophin leads to theappearance of lesions of the membranes covering the muscle cells(myocytes), involving the degeneration and necrosis of musclefibers miocitara.

In some cases, the disease manifests dystrophy since the embryonic stage, but in others, it occurs after age 3 or 4 years.Affected children require more time to learn to walk than normal.They have a roll, or peaks and difficulty in climbing stairs, runningor lifting from the ground. Fall trend is pronounced.

After the first symptoms, the disease progresses rapidly. Notecontractures (involuntary contractions) and scoliza. Despite theweakness, muscle fibers appear hypertrophied by replacing thelost muscle or fat tissue. At age 12, children lose their ability towalk and are immobilized in a wheelchair. In one third of cases are found and impaired intellectual function (especially verbal skills).Generally, death occurs at 20 years due to respiratorycomplications and heart failure.