What is exactly FOP?
Fibrodysplasia Ossificans Progressiva also knows as FOP and myositis ossificans progressiva is a rare genetic tissue disease that is characterized by the abnormal development of bone in areas of the body where the bone is not normally present such as the ligaments, tendons, and skeletal muscles.
The body’s skeletal muscles and soft connective tissues undergo metamorphosis hence turning the soft tissues into hard skeletal bones and locking up joints which eventually leads to the disability in movement.
The individuals affected by this disease have big toes that are present since birth, after some time more abnormal developments occur which causes stiffness in the areas which are affected, causing limited movements, and eventual fusion of affected joints. This often follows the order: neck, back, shoulders, elbows, hips knees, wrists, ankles, and jaw.
Inflammatory soft tissue swellings are something that begins in childhood and continues to progress throughout the lifetime. Sporadic new mutation and genetic mutation are the causes of this rare syndrome. FOP is the result of the mutation of a gene (ACVR1) which is present in the bone morphogenetic protein (BMP) pathway, which is significant for the formation of the skeleton in the embryo and for the repair of the skeleton following birth.
Signs & Symptoms:
All patients having this disorder are usually affected by big toes, and almost half of the individuals have big thumbs, which they have since they are born and are the clinical symptoms of this disease. Bone and joint problems make it hard for babies to learn to crawl.
Bone overgrowth tends to start in the neck and shoulders, causing periodic bouts of painful inflammation. This is sometimes accompanied by a low-grade fever. The disease progresses at a different rate for each person.
A shortened great toe with a malformed distal first metatarsal and a missing or abnormal first phalanx and/or interphalangeal joint is the most common malformation. Inward turning of the great toe toward the other toes, abnormally short fingers and, and/or permanent fixation of the fifth finger in a bent position is the other transformation that can be observed in toes and fingers.
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Proximal medial tibial osteochondromas, malformation of the upper part of the spinal column (cervical vertebrae), and an abnormally short broad neck of the bone in the thigh that extends from the knee to the pelvis (femur) are other signs which are shown by the patients, since birth who have this disorder. Movements can become severely restricted as the bone grows into joints. The spine can become deformed.
Balance and coordination problems are caused because of limited mobility which leads to injury due to falling. Even a minor injury causes more inflammation and bone growth. Bone growth in the chest can restrict breathing, increasing the risk of respiratory infection. Any viral illness can trigger a flare-up.
Malnutrition and weight loss can be caused due to the limited movement of the jaw which can make it hard to eat. Talking can also be difficult. About half of people with FOP experience hearing impairment. Swellings are caused because poor blood flow can lead to the pooling of the blood in the arms or legs. A person with FOP can eventually become completely immobilized.
Tongue, diaphragm, extraocular muscles, cardiac muscle, and smooth muscles are some areas where bones don’t grow.
Cause:
In April 2006, an international team of researchers led by Eileen M. Shore, Ph.D., and Frederick Kaplan MD of the University of Pennsylvania, and found that FOP is caused by a mutation in the ACVR1 gene. This gene is involved in the growth and development of bones.
The mutation allows them to grow unchecked. The gene can be inherited from one parent, but in most cases of FOP, it’s a new mutation in a person with no family history of the disease. Dominant genetic disorders are caused by abnormal DNA sequence changes in one of the two copies of a given gene.
A parent with FOP has a 50 percent chance of passing it
on to their child. The risk is the same for males and females.
Affected Populations:
This rare syndrome was first depicted in the 18th century. Worldly, 4000 affected individuals are affected and approximately 900 known patients are known with 285 of them in the United States.
Both genders and all ethnicities are affected by this disease. New episodes of bone growth can be caused at any time, spontaneously without any reason.
FOP can become severely disabling. Most people with FOP will need a wheelchair by the time they reach their late 20s. The median lifespan for people with FOP is 40 years.
Diagnosis:
Most doctors don’t check the presence of this disorder because this disorder is really rare. The diagnosis depends on medical history and clinical examination.
Imaging tests such as X-rays and MRIs help in see the excess formation of bones but are really not necessary. The confirmation can be received by the genetic diagnosis.
The chance of misdiagnosis is more than 80 percent. The most common misdiagnoses are cancer, aggressive juvenile fibromatosis, and fibrous dysplasia. The common symptom is malformed toes or hands.
It is really significant to get the “right” diagnosis as
soon as possible. That’s because certain tests and treatments for other
conditions can result in encouragement to bone growth.
Treatment:
There’s no possible treatment that can slow or stop this disease. But there exists a treatment for specific symptoms which can improve the quality of life for the patient. Pain and swelling during flare-ups can decrease by corticosteroids, non-steroidal anti-inflammatory drugs (NSAIDs) between flare-ups, assistive devices such as braces or special shoes can help with walking and occupational therapy.
The new bones don’t have any substitute and surgeries result in more and more formation of bones. Various viral illnesses including influenza and influenza-like illnesses may provoke flare-ups of the condition.
An important part of your treatment plan has to do with what to avoid such as a biopsy will result in rapid bone growth to the area.
Intramuscular injections, such as most immunizations, can also cause trouble. Dental work should be performed with extra care, avoiding injections and stretching of the jaw.
Blunt trauma or injury due to falling can cause swelling. Any physical activities that increase these risks should be avoided.
FOP can be dangerous during pregnancy, which can increase the chances of flare-ups and complications for both mother and baby.
Special shoes, braces, and other devices can help the patients in lifting up weight and walking. They can also contact physicians who can help them get special devices or tools to assist them in daily activities.
Genetic counseling can help families with the inheritance of FOP. Another treatment is symptomatic and supportive.
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