Spondylo-meta-epiphyseal dysplasia

Autosomal recessive - en

Spondylo-meta-epiphyseal dysplasia (SMED) is a rare genetic disorder that affects the bone development in the body. This condition is characterized by abnormalities in the vertebrae (spondylo-), the ends of long bones (meta-), and the growth regions at the ends of these bones (epiphyseal). Individuals with SMED often present with a short stature, skeletal deformities, and sometimes problems related to vision and hearing.

Causes

SMED is caused by mutations in specific genes that are important for the development and maintenance of bone and cartilage. These mutations are usually inherited in an autosomal recessive manner, meaning that an individual must inherit two copies of the mutated gene, one from each parent, to be affected by the disorder.

Symptoms

The symptoms of SMED can vary significantly among affected individuals but commonly include:

• Short stature, often noticeable from birth or early childhood
• Skeletal deformities, including abnormal curvature of the spine (scoliosis or kyphosis), hip dysplasia, and abnormalities in the shape of the long bones
• Delayed bone age
• Problems with vision and hearing in some cases

Diagnosis

Diagnosis of SMED is based on the clinical presentation and radiographic findings. Magnetic resonance imaging (MRI) and X-rays can reveal characteristic abnormalities in the spine, long bones, and other areas affected by the disorder. Genetic testing can confirm the diagnosis by identifying mutations in the genes associated with SMED.

Treatment

There is no cure for SMED, and treatment focuses on managing symptoms and improving quality of life. This may include:

• Orthopedic interventions, such as surgery, to correct skeletal deformities and improve mobility
• Physical therapy to strengthen muscles and improve movement
• Regular monitoring and treatment for vision and hearing problems

Prognosis

The prognosis for individuals with SMED varies depending on the severity of the symptoms and the success of management strategies. With appropriate care, most individuals with SMED can lead active lives, although they may face challenges related to their skeletal deformities and stature.

See also

• Dwarfism
• Osteochondrodysplasia
• Genetic disorders