Birt-Hogg-Dube syndrome is a hereditary condition which is associated with multiple non cancerous skin tumours. Birt-Hogg-Dube syndrome is also called as BHD and Hornstein–Knickenberg syndrome. The disease is named after the scientists who discovered it. The disease was first described in 1977 by three doctors named, Arthur R. Birt, Georgina R. Hogg and William J. Dube. It is a genetic disorder and symptoms vary from person to person. Patients suffering from BHD experience skin lesions on the face, neck and upper chest. In few cases Birt-Hogg-Dube syndrome also leads to lung cyst, kidney cancer and collapsed lungs. People between 20 to 30 years of age are mainly affected with Birt-Hogg-Dube syndrome and show visible symptoms. Generally people suffering with Birt-Hogg-Dube syndrome experience abnormal accumulation of air in the chest cavity. Abnormal accumulation of air in the chest cavity is also known as pneumothorax. Pneumothorax may result in the collapse of a lung in severe cases. Birt-Hogg-Dube syndrome is a very rare genetic disorder caused due to mutations in the specific genes.
Birt-Hogg-Dube syndrome is caused due to gene mutations. Mutations in FLCN gene cause Birt-Hogg-Dube syndrome. FLCN gene is known to be tumour suppressor gene. These tumour suppressor genes are responsible to give instructions for making a protein called folliculin. Folliculin is present in brain, placenta, testis, skin, lung, kidney and heart. Folliculin plays an important role in structural framework of a cell and interactions between cells. Folliculin is known for restraining cell growth. Mutations in FLCN gene interfere in folliculin activity. The interference in folliculin ability to restrain cell growth and division results in uncontrolled cell growth. Uncontrolled cell growth can lead to formation of cancerous and non cancerous tumours. Presence of altered FLCN gene in one of the parent cell can cause Birt-Hogg-Dube syndrome. Single copy of mutated FLCN gene can cause skin cancer and lung disorders. There are 2 copies of each gene present in the body. Recent research says that mutation in both the copies of FLCN gene can cause Birt-Hogg-Dube syndrome.
Birt-Hogg-Dube syndrome patients show visible symptoms. Symptoms of Birt-Hogg-Dube syndrome vary in each patient. Patients with different symptoms can help the researchers and clinicians by giving details about the symptoms to avoid any future risk and complications. Around 500-600 families are reported to have Birt-Hogg-Dube syndrome globally. The common symptoms include:
- Benign skin lesions
- Lung cyst
- Non cancerous dome shaped hair follicle tumour
- Non cancerous tumour on upper chest
- Non cancerous tumour on neck
- Non cancerous tumour on face
Birt-Hogg-Dube syndrome can be diagnosed only by genetic tests. Genetic tests are preferred when compared to other tests in patients as it is a genetic disorder caused due to mutations in FLCN gene. Birt-Hogg-Dube syndrome diagnosis generally create confusion as there are many other diseases which can result in skin lesions, skin cancers, lung disorder and kidney related disorders. Computed tomography scan of the lungs are recommended to detect pulmonary cyst or pheumothorax.
Laser therapy – Standard therapy for treating Birt-Hogg-Dube syndrome includes the use of laser beam. Laser beam is used to destroy affected skin tissue. Skin lesions are often treated with laser therapy, but the lesions generally relapse after the treatment. In severe cases surgery is required to remove the tumours. Renal neoplasia generally requires surgery to prevent the kidneys from further damage.