Hereditary multiple exostoses (HME), also known as multiple hereditary exostoses (MHE), is a rare genetic disorder characterized by the development of multiple benign bone tumors called osteochondromas. These tumors typically grow near the growth plates of long bones, such as the arms and legs, but can also occur in other bones throughout the body.
Individuals with HME may experience a wide range of symptoms depending on the location and number of osteochondromas. Common symptoms include bone deformities, limb length discrepancies, joint pain, limited range of motion, and nerve compression. In some cases, the tumors can become malignant, although this is rare.
Hereditary multiple exostoses is an autosomal dominant condition, meaning that a person only needs to inherit the mutated gene from one parent to develop the disorder. The gene mutations associated with HME are typically found in the EXT1 or EXT2 genes, which are responsible for producing proteins involved in bone growth and development.
Diagnosis of HME is usually made based on clinical evaluation, medical history, and imaging studies such as X-rays or MRI scans. Genetic testing can also be performed to confirm the presence of gene mutations.
Treatment for hereditary multiple exostoses focuses on managing symptoms and preventing complications. This may involve regular monitoring of tumor growth, physical therapy to improve joint function and mobility, pain management, and surgical removal of problematic osteochondromas. In cases where malignant transformation occurs, more aggressive treatment options such as chemotherapy or radiation therapy may be necessary.
Living with HME can present challenges, both physically and emotionally. Supportive care from healthcare professionals, genetic counseling, and participation in patient support groups can help individuals and their families cope with the impact of the condition.