Fibrous dysplasia
May 2nd, 2008 Posted by: admin
What is fibrous dysplasia?
Fibrous dysplasia is a chronic disorder in which bone expands due to abnormal development of fibrous tissue, often resulting in one, or more, of the following:
- uneven growth of bones
- pain
- brittle bones
- bone deformity
Any bone can be affected. More than one bone can be affected at any one time, and, when multiple bones are affected, it is not unusual for them to all be on one side of the body. However, fibrous dysplasia does not spread from one bone to another.
Fibrous dysplasia usually occurs in childhood, but it sometimes is not diagnosed until adulthood. It is found equally among males and females.
Causes
The exact cause of fibrous dysplasia is not known, but it is believed to be due to a structural abnormality in a specific bone protein, caused by a gene mutation present at birth.
It is not known to be an inherited disorder.
Fibrous dysplasia disrupts the process of bone renewal, causing old bone to break down faster and replacing normal bone tissue with softer, fibrous tissue.
Symptoms
The following are the most common symptoms for fibrous dysplasia. However, each individual may experience symptoms differently. Symptoms may include:
- Bone pain
- Difficulty walking
- Bone deformities
- Fractures
- Scoliosis
The symptoms of fibrous dysplasia may resemble other bone disorders or medical problems. Always consult your physician for a diagnosis.
Other features
- Fibrous dysplasia may be associated with endocrinopathies in 2-3% of cases; these include precocious puberty in girls, hyperthyroidism, hyperparathyroidism, acromegaly, diabetes mellitus, and Cushing syndrome. McCune-Albright syndrome may be associated with hyperthyroidism and, hence, exophthalmos.
- Cutaneous pigmentation is the most common extraskeletal manifestation in fibrous dysplasia. Cutaneous pigmentation in polyostotic fibrous dysplasia is ipsilateral to the side of bony lesions, a feature that differentiates this disease from pigmentation in neurofibromatosis. Pigmentation may occur at birth, and in fact, it occasionally precedes the development of skeletal and endocrine abnormalities.
- The prevalence rate of scoliosis in patients with polyostotic fibrous dysplasia is 40-52%. Most spinal lesions are located in the lumbar and thoracic spines.
- In McCune-Albright syndrome sexual precocity occurs in girls, with polyostotic fibrous dysplasia and cutaneous pigmentation.
- The only significant laboratory abnormality is an elevated alkaline phosphatase level.
Types
Monostotic form: Approximately 70-80% of fibrous dysplasias are monostotic.
Polyostotic form: Approximately 20-30% of fibrous dysplasias are polyostotic.
Craniofacial form occurs in 10-25% of patients with the monostotic form and in 50% with the polyostotic form.
Cherubism is a special variant of fibrous dysplasia, that occurs in childhood and is more severe in boys.
See more on: http://www.emedicine.com/RADIO/topic284.htm
Screening and Diagnosis
In addition to a complete medical history and physical examination, diagnostic procedures for fibrous dysplasia may include the following:
- x-ray
- biopsy
- computed tomography scan (Also called a CT or CAT scan.)
- blood tests
These are also used to determine the extent of the disorder (screening) while being under the continous medical observation as a patient with fibrous dysplasia.
See more on: http://www.emedicine.com/RADIO/topic284.htm
Possible Complications
Bone deformity
· Vision and hearing loss
· Arthritis
· Cancer (rarely)
Treatment for fibrous dysplasia:
Specific treatment for fibrous dysplasia will be determined by your physician tacking into consideration :
- your age, overall health, and medical history
- extent of the disease
- your tolerance for specific medications, procedures, or therapies
Treatment may include:
medication : bisphosphonates, including pamidronate (Aredia) and alendronate (Fosamax), They are not often used in treating children, but some studies indicate they may help relieve pain in children and adolescents with severe fibrous dysplasia.
They can be adminstered orally or intravenously.Bisphosphonates are not indicated if you have serious kidney disease or low blood calcium levels.
pain management
physical therapy
surgery might be needed; it is’n neccessary in all cases.