Desmin-related myofibrillar myopathy

Desmin-related myofibrillar myopathy (DRM) is a type of myopathy that primarily affects the skeletal muscles and cardiac muscle. It is characterized by the accumulation of desmin, a type of intermediate filament protein, in muscle cells. This condition is a subtype of the broader category of myofibrillar myopathies.

Etiology

DRM is caused by mutations in the DES gene, which provides instructions for making desmin. Desmin is a protein that plays a crucial role in maintaining the structural integrity and proper functioning of muscle cells. Mutations in the DES gene disrupt the normal assembly of desmin proteins into intermediate filaments, leading to the formation of abnormal aggregates of desmin and other proteins in muscle cells.

Clinical Features

The clinical features of DRM can vary widely among affected individuals. Symptoms typically begin in adulthood and can include muscle weakness and wasting, cardiac abnormalities such as cardiomyopathy, and respiratory problems. In some cases, DRM can also affect the nerves, leading to neuropathy.

Diagnosis

Diagnosis of DRM is based on clinical symptoms, family history, and specialized tests such as muscle biopsy and genetic testing. A muscle biopsy can reveal the characteristic desmin aggregates in muscle cells, while genetic testing can identify mutations in the DES gene.

Treatment

There is currently no cure for DRM. Treatment is symptomatic and supportive, and may include physical therapy, respiratory support, and management of cardiac complications.

Prognosis

The prognosis for individuals with DRM varies depending on the severity of symptoms and the presence of cardiac involvement. Some individuals may have a normal lifespan with mild symptoms, while others may experience severe disability and life-threatening cardiac complications.

See Also

• Myopathy
• Cardiomyopathy
• Neuropathy