Myotonic dystrophies

What is it?

Dystrophy is a disease characterized by progressive muscle weakness mainly in the distal muscles of the extremities in type 1 diabetes and in the proximal muscles in type 2 diabetes. Muscle weakness is associated with a myotonic phenomenon characterized by the difficulty of relaxing muscles after contraction, for example, when the arm is released again after grasping an object. Both of them are multisystem diseases, since in addition to muscles, they can also affect other organs, including the heart (cardiac conduction disorders, arrhythmias, cardiomyopathies), the respiratory system, eyes (cataracts), genitals (decreased fertility), the endocrine system (hypothyroidism, diabetes ) and the central nervous system (mental retardation, behavioral disorders). The involvement of these systems is more common in type 1 diabetes and is only partially present in type 2 forms.

The age of onset of the disease is very different, although it is more common in the second and third decades. Congenital forms are also present, usually in newborns from affected mothers, with mild forms that are almost completely asymptomatic. The disease is usually the more severe, the earlier it appears. The complications that threaten the survival of these patients the most are arrhythmias, which can lead to sudden death.

Causes and risk factors

The disease is transmitted in an autosomal dominant way: a sick parent has a 50% chance of transmitting the disease to every child, regardless of gender. These are the so-called nucleotide expansion diseases, CTG of the DMPK gene for type 1 diabetes and CCTG of the ZNF9 gene for type 2 diabetes, to cover thousands of triplets: the more extensive this repetition, the more severe the disease. The disease is also characterized by the so-called expectation phenomenon, in which it tends to worsen and appear earlier during the transition from one generation to the next.

How is it diagnosed?

A suspicion of a diagnosis is formulated on the basis of clinical observation: confirmation is given by electromyographic research and, above all, by genetic analysis. An antenatal diagnosis can be made.

How is it treated?

There is no definitive therapy at this time. However, it is possible to intervene in a complex manner using various types of therapy (cardiological, endocrinological, respiratory, orthopedic, physiotherapy, etc.) to improve the quality of life. In particular, periodic cardiac check-ups allow early detection of the onset of cardiac arrhythmias and prevent sudden death by implanting a pacemaker or defibrillator. Some muscle relaxants can also reduce myotonic effects.

Where do we treat it?

Within the San Donato Group, you can find Myotonic dystrophies specialists at these departments:

Are you interested in receiving the treatment?

Contact us and we will take care of you.