Familial Osteoma Cutis - Causes, Symptoms, Diagnosis, and Management

Introduction:

Familial osteoma cutis is a rare genetic disorder (acquired due to defective genes). The formation of bony growths on the skin is characteristic of it. These bony growths are known as osteomas, benign tumors (not spread to other regions) made up of compact bone tissue (type of bone) commonly seen on the face, scalp, and ears. Size ranges from small, barely visible bumps to large growths. The bone tissue typically develops from an inflammatory scar or granuloma in a calcification center. There is no malignancy in osteoma cutis. Instead, it is inherited in an autosomal dominant pattern, meaning that an affected individual has a 50% chance of passing the condition on to each of their offspring.

What Are the Causes of Familial Osteoma Cutis?

A genetic mutation (alteration) in the guanine nucleotide-binding protein, alpha stimulating (GNAS) gene, causes familial osteoma cutis. The GNAS gene provides information and instructions for making a protein known as G protein-coupled receptor (GPCR). This protein plays an essential role in bones' general growth and development. In addition, this protein helps regulate the signaling pathways that form and maintain bone tissue. The specific case of the mutation still needs to be fully understood. Still, it is believed that the mutation leads to the development of overactive GPCR signaling that results in the overproduction of bone tissue. This overproduction of bone tissue leads to the formation of osteomas.

What Are the Symptoms of Familial Osteoma Cutis?

The symptoms of familial osteoma cutis vary depending on the size and location of the osteomas. Some of the common symptoms include the following -

• Small or barely visible growth on the skin.

• Sometimes large, disfiguring growths are seen.

• Growth is hard and firm to the touch.

• Growth is slightly raised or flushed with the skin.

• In general, osteomas do not cause pain but become painful if they apply pressure on a nerve or when infected.

• This growth leads to the disfigurement of the face, scalp, or ears.

• Due to their unesthetic appearance, patients have difficulty maintaining self-esteem and body image issues.

• Difficulty with social and occupational functioning.

What Are the Complication of Familial Osteoma Cutis?

Apart from symptoms, familial osteoma cutis can cause other complications as well. These may include the following -

• Obstructing the Airways - Osteomas that grow on the face (particularly in the nose or ears) can block the airways and lead to difficulty in breathing.

• Hearing Loss - Osteomas that grow near the ears can block the ear canal, which leads to cause hearing loss.

• Vision loss - Osteomas that grow on the eyelids can cause vision loss.

• Sinusitis - Osteomas can cause sinusitis (inflammation of the sinus wall) if they develop in the sinuses.

• Recurrent Infections - Osteomas can accumulate high bacterial counts if they grow on the scalp, become infected, and lead to recurrent infections.

What Are the Diagnosis of Familial Osteoma Cutis?

Familial osteoma cutis is diagnosed with the help of a combination of physical examination, medical history, and imaging tests.

• Physical Examination - A doctor checks the characteristics of bony growths on the skin during a physical examination. Doctors may also take a medical history to determine if the patient has a positive family history of the disorder.

• Imaging Test - Imaging tests are used to confirm the diagnosis. These may include the following -

1. X-ray - In an X-ray, a small amount of radiation is used to create detailed images of the bones. It can help to confirm the presence of osteomas. It also helps in the determination of the size and location of osteoma.

2. CT Scan - A CT scan (computed tomography) which utilizes X-rays and a computer creates cross-sectional images of the body. It can help to provide more detailed information about the osteomas, such as their shape and location.

3. MRI - It is known as magnetic resonance imaging. An MRI creates detailed images of the body with the help of magnetic and radio waves. It can help to provide more detailed information about the osteomas, such as their shape and location.

• Biopsy - A small piece of tissue may be taken from the osteoma and analyzed under a microscope to confirm the diagnosis.

• Dermoscopy - This non-invasive method uses a special microscope to examine the skin. Dermoscopy can help to identify the characteristic features of osteomas, such as the presence of small blood vessels, which can aid in the diagnosis.

• Histopathology - This laboratory test examines a small piece of tissue taken from the osteoma under a microscope. Histopathology confirms the diagnosis by identifying the characteristic bony tissue of osteomas.

What Is the Treatment of Familial Osteoma Cutis?

Treatment options include the following:

• Observation - A doctor recommends only observation if it is small and does not cause any symptoms. Usually, it is done where osteomas are not in a visible location.

• Surgery - Surgery is the most common treatment option for familial osteoma cutis. Surgery removes the osteomas and improves the patient's appearance. Surgery may include:

1. Excision - This involves cutting the osteoma and its surrounding tissue. It is the most common surgical treatment used in cases of osteomas.

2. Curettage and Electrodesiccation - This involves scraping the osteoma and cauterizing the remaining tissue (electrical removal). It is a less invasive procedure than excision. It is usually done for smaller osteomas.

3. Cryosurgery - It involves freezing the osteoma with the use of liquid nitrogen. It uses for smaller osteomas that are difficult to remove surgically.

• Dermatological Treatment - These treatments are not definitive. It may include applying topical agents, photodynamic therapy, and laser therapy.

• Radiotherapy - It involves the use of high-energy radiation to destroy the cells of the osteoma. This treatment is not commonly used but may be considered when surgery can not be performed.

• Medications - No specific drugs are used in treatment, but doctors give pain medication if the patient is experiencing pain.

Conclusion:

An uncommon hereditary condition known as familial osteoma cutis causes bony skin growths to appear. It occurs due to a mutation in the gene that regulates bone production. Depending on various conditions, the disorder's symptoms can vary. Symptom management is the goal of laser therapy and surgery. People with this illness should seek medical attention as soon as possible to avoid complications.