Cherubism

Cherubism

A child with cherubism, showing characteristic facial swelling.

Cherubism is a rare genetic disorder that affects the bones of the face, particularly the jawbones. It is characterized by painless, progressive swelling of the cheeks and jaw, giving the affected individuals a cherubic appearance, hence the name.

Etiology

Cherubism is caused by mutations in the SH3BP2 gene, which is located on chromosome 4. This gene is responsible for producing a protein involved in the regulation of bone metabolism. The mutation leads to abnormal bone remodeling, resulting in the characteristic facial features of the disorder.

Clinical Features

The primary clinical feature of cherubism is bilateral swelling of the cheeks due to the overgrowth of the jawbones. This typically becomes apparent in early childhood, around the age of 2 to 7 years. The condition progresses until puberty, after which it often stabilizes or regresses.

Other features may include:

• Dental abnormalities, such as malocclusion, displacement of teeth, and delayed eruption.
• Ocular issues, such as upward displacement of the eyes, giving a "heavenward gaze" appearance.
• In some cases, hearing loss due to involvement of the bones surrounding the ear.

Pathophysiology

The pathophysiology of cherubism involves the replacement of normal bone with fibrous tissue and cyst-like structures. This process is driven by the abnormal activity of osteoclasts and osteoblasts, which are cells responsible for bone resorption and formation, respectively.

Diagnosis

Diagnosis of cherubism is primarily clinical, based on the characteristic facial appearance and family history. Radiographic imaging of the jaws reveals multilocular radiolucencies, often described as "soap bubble" or "honeycomb" appearances. Genetic testing can confirm the diagnosis by identifying mutations in the SH3BP2 gene.

Management

Management of cherubism is largely supportive and symptomatic. Regular dental care is essential to address dental issues. In some cases, surgical intervention may be necessary to correct severe deformities or functional impairments. The condition often stabilizes or improves after puberty, reducing the need for aggressive treatment.

Prognosis

The prognosis for individuals with cherubism is generally good. The facial swelling often regresses after puberty, and many individuals experience significant improvement in appearance. However, dental and skeletal issues may persist and require ongoing management.

Related pages

• Fibrous dysplasia
• Genetic disorders
• Osteoclast
• Osteoblast