Emery–Dreifuss muscular dystrophy

Emery–Dreifuss muscular dystrophy can be sub classified by pattern of inheritance: X linked, autosomal dominant, and autosomal recessive. Autosomal dominant: heart problems with weakness (and wasting) of skeletal muscles and Achilles tendon contractures. X linked: result of the EMD gene mutation, characterized by cardiac involvement. Autosomal recessive: characterized by cardiac issues, such as arrhythmia.

Genetic mutations causing EDMD affect proteins comprising the nuclear membrane. Possibly, in all EDMD subtypes there is impaired protein importation into the nucleus. Another possibility is that in all subtypes, there is a loss of nuclear structural integrity.

A positive genetic test in a person with the signs and symptoms of EDMD provides definitive diagnosis. Genetic testing can involve single gene testing or genomic testing. Auxiliary testing can include the following:

Contractures manifest early in the disease course. Other diseases that have early or congenital contractures are diseases involving collagen mutations, including Ullrich congenital muscular dystrophy and Bethlem myopathy. SELENON related myopathy and arthrogryposis multiplex congenita also cause congenital contractures. Weakness initially affects the humeral and peroneal muscles, progressing to involve the scapular and pelvic muscles. Facioscapulohumeral muscular dystrophy has a similar muscle involvement pattern.

Following diagnosis, extent of disease should be established in regards to the heart, the lungs, and the muscles/bones (musculoskeletal). Metabolic functions should also be assessed, as lipodystrophy can co occur with EDMD, by measuring levels of sugar, cholesterol, and triglycerides in the blood. Tests useful for heart evaluation include electrocardiography (EKG), echocardiography (echo), cardiac MRI, and electrophysiology studies. Musculoskeletal function can be assessed by a physical therapist or orthopedist. Regardless of extent of disease, cardiac and respiratory complications should be monitored for. EKG, holter, and echo are recommended yearly, and additional tests can be indicated depending on heart involvement. Pulmonary function tests (PFTs) are recommended every 2–3 years, or yearly in those with respiratory involvement. Although the root cause of EDMD is not currently treatable, its manifestations and complications can be treated. Heart involvement can be addressed with medications (antiarrhythmics, beta blockers, and ACE inhibitors), pacemakers, defibrillators, and sometimes heart transplantation. Affecting breathing can be addressed with physical therapy and, later in disease, mechanical ventilation. Contractures and scoliosis can be addressed with orthopedic surgery. Mobility can be improved with physical therapy, occupational therapy, and mechanical aids (canes, orthoses, wheelchairs).

It is rare, affecting 0.39 per 100,000 (1 per 250,000) people. Type Incidence EDMD1 0.13 0.2 per 100,000 EDMD2 Majority of EDMD cases EDMD3 10 reported cases EDMD4 1 человек EDMD5 EDMD6 1% of EDMD cases EDMD7