Ullrich congenital muscular dystrophy

A form of congenital muscular dystrophy

Ullrich congenital muscular dystrophy (UCMD) is a rare genetic disorder characterized by muscle weakness and joint abnormalities. It is one of the forms of congenital muscular dystrophy, a group of muscle diseases that are present at birth or in early infancy.

Etiology

UCMD is caused by mutations in the genes that encode for collagen VI, a protein that is essential for the structural integrity of muscle tissue. The specific genes involved are COL6A1, COL6A2, and COL6A3. These mutations lead to defects in the collagen VI protein, resulting in muscle weakness and other symptoms associated with the disorder.

Clinical Features

Individuals with UCMD typically present with muscle weakness that is evident at birth or in early childhood. The muscle weakness is often accompanied by joint contractures, which are limitations in the range of motion of the joints. Other common features include:

• Hypotonia (decreased muscle tone)
• Hyperlaxity (increased flexibility) of distal joints
• Kyphoscoliosis (curvature of the spine)
• Respiratory difficulties due to weakness of the respiratory muscles
• Skin changes such as keratosis pilaris

Diagnosis

The diagnosis of UCMD is based on clinical examination, family history, and genetic testing. Muscle biopsy may show characteristic changes, and immunohistochemical staining can reveal abnormalities in collagen VI. Genetic testing can confirm mutations in the COL6A1, COL6A2, or COL6A3 genes.

Management

There is currently no cure for UCMD, and treatment is primarily supportive. Management strategies include:

• Physical therapy to maintain mobility and prevent contractures
• Orthopedic interventions for joint deformities
• Respiratory support, such as non-invasive ventilation, for individuals with respiratory muscle weakness
• Regular monitoring by a multidisciplinary team including neurologists, pulmonologists, and orthopedic specialists

Prognosis

The prognosis for individuals with UCMD varies depending on the severity of the condition. Some individuals may have a relatively stable course, while others may experience progressive muscle weakness and respiratory complications. Early intervention and supportive care can improve quality of life and functional outcomes.

Related pages

• Congenital muscular dystrophy
• Collagen
• Genetic disorder
• Muscle biopsy