Myopathy, desmin storage

Desmin Storage Myopathy is a rare genetic disorder characterized by the abnormal accumulation of desmin protein in the muscle cells. Desmin is a type of intermediate filament that plays a crucial role in the structural integrity and function of muscle cells. In desmin storage myopathy, mutations in the genes responsible for desmin production lead to the formation of abnormal desmin aggregates, which interfere with normal muscle function.

Causes

Desmin storage myopathy is caused by mutations in the DES gene, which encodes the desmin protein. These mutations lead to the production of an abnormal desmin that aggregates within muscle cells. The condition is inherited in an autosomal dominant manner, meaning that only one copy of the altered gene is sufficient to cause the disorder. However, cases have been reported where the disease occurs due to a new mutation in the gene and is not inherited from either parent.

Symptoms

The symptoms of desmin storage myopathy can vary widely among affected individuals but generally include muscle weakness (myopathy), heart problems (cardiomyopathy), and sometimes respiratory issues. The onset of symptoms can occur at any age but typically begins in adulthood. Muscle weakness often starts in the lower limbs and can progress to affect the upper limbs and other muscle groups. The severity of the condition can also vary, with some individuals experiencing mild symptoms and others developing severe disabilities over time.

Diagnosis

Diagnosis of desmin storage myopathy involves a combination of clinical evaluation, family history, and genetic testing to identify mutations in the DES gene. Muscle biopsy may also be performed, where a small sample of muscle tissue is examined under a microscope to detect the presence of desmin aggregates.

Treatment

There is currently no cure for desmin storage myopathy, and treatment focuses on managing symptoms and improving quality of life. This may include physical therapy to maintain muscle strength and mobility, use of assistive devices to aid in movement, and medications to manage heart and respiratory symptoms. In some cases, individuals may require surgical interventions to manage complications.

Prognosis

The prognosis for individuals with desmin storage myopathy varies depending on the severity of symptoms and the onset of the disease. While the condition can lead to significant disability, many individuals are able to lead active lives with appropriate management and support.