What is exactly FOP?
Fibrodysplasia Ossificans Progressiva also knows as FOPand myositis ossificans progressiva is a rare genetic tissue disease that ischaracterized by the abnormal development of bone in areas of the body wherethe bone is not normally present such as the ligaments, tendons, and skeletalmuscles.
The body’s skeletal muscles and soft connective tissuesundergo metamorphosis hence turning the soft tissues into hard skeletal bonesand locking up joints which eventually leads to the disability in movement.
The individuals affected by this disease have big toesthat are present since birth, after some time more abnormal developments occurwhich causes stiffness in the areas which are affected, causing limitedmovements, and eventual fusion of affected joints. This often follows theorder: neck, back, shoulders, elbows, hips knees, wrists, ankles, and jaw.
Inflammatory soft tissue swellings are something thatbegins in childhood and continues to progress throughout the lifetime. Sporadicnew mutation and genetic mutation are the causes of this rare syndrome. FOP isthe result of the mutation of a gene (ACVR1) which is present in the bonemorphogenetic protein (BMP) pathway, which is significant for the formation ofthe skeleton in the embryo and for the repair of the skeleton following birth.
Signs & Symptoms:
All patients having this disorder are usually affected bybig toes, and almost half of the individuals have big thumbs, which they havesince they are born and are the clinical symptoms of this disease. Bone andjoint 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 accompaniedby a low-grade fever. The disease progresses at a different rate for eachperson.
A shortened great toe with a malformed distal firstmetatarsal and a missing or abnormal first phalanx and/or interphalangeal jointis the most common malformation. Inward turning of the great toe toward theother toes, abnormally short fingers and, and/or permanent fixation of the fifth finger in a bent position is the other transformation that can beobserved in toes and fingers.
Proximal medial tibial osteochondromas, malformation ofthe upper part of the spinal column (cervical vertebrae), and an abnormallyshort broad neck of the bone in the thigh that extends from the knee to thepelvis (femur) are other signs which are shown by the patients, since birth whohave this disorder. Movements can become severely restricted as the bone growsinto joints. The spine can become deformed.
Balance and coordination problems are caused because oflimited mobility which leads to injury due to falling. Even a minor injurycauses more inflammation and bone growth. Bone growth in the chest can restrictbreathing, increasing the risk of respiratory infection. Any viral illness cantrigger a flare-up.
Malnutrition and weight loss can be caused due to thelimited movement of the jaw which can make it hard to eat. Talking can also bedifficult. About half of people with FOP experience hearing impairment.Swellings are caused because poor blood flow can lead to the pooling of theblood in the arms or legs. A person with FOP can eventually become completelyimmobilized.
Tongue, diaphragm, extraocular muscles, cardiac muscle, andsmooth muscles are some areas where bones don’t grow.
Cause:
In April 2006, an international team of researchers ledby Eileen M. Shore, Ph.D., and Frederick Kaplan MD of the University ofPennsylvania, 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. Thegene can be inherited from one parent, but in most cases of FOP, it’s a newmutation in a person with no family history of the disease. Dominant geneticdisorders are caused by abnormal DNA sequence changes in one of the two copiesof a given gene.
A parent with FOP has a 50 percent chance of passing iton to their child. The risk is the same for males and females.
Affected Populations:
This rare syndrome was first depicted in the 18thcentury. Worldly, 4000 affected individuals are affected and approximately 900known patients are known with 285 of them in the United States.
Both genders and all ethnicities are affected bythis disease. New episodes of bone growth can be caused at any time,spontaneously without any reason.
FOP can become severely disabling. Most people with FOPwill need a wheelchair by the time they reach their late 20s. The medianlifespan for people with FOP is 40 years.
Diagnosis:
Most doctors don’t check the presence of this disorderbecause this disorder is really rare. The diagnosis depends on medical historyand clinical examination.
Imaging tests such as X-rays and MRIs help in see theexcess formation of bones but are really not necessary. The confirmation can bereceived by the genetic diagnosis.
The chance of misdiagnosis is more than 80 percent. Themost common misdiagnoses are cancer, aggressive juvenile fibromatosis, andfibrous dysplasia. The common symptom is malformed toes or hands.
It is really significant to get the “right” diagnosis assoon as possible. That’s because certain tests and treatments for otherconditions can result in encouragement to bone growth.
Treatment:
There’s no possible treatment that can slow or stop thisdisease. But there exists a treatment for specific symptoms which can improvethe quality of life for the patient. Pain and swelling during flare-ups candecrease by corticosteroids, non-steroidal anti-inflammatory drugs (NSAIDs)between flare-ups, assistive devices such as braces or special shoes can helpwith walking and occupational therapy.
The new bones don’t have any substitute and surgeriesresult in more and more formation of bones. Various viral illnesses includinginfluenza and influenza-like illnesses may provoke flare-ups of the condition.
An important part of your treatment plan has to do withwhat to avoid such as a biopsy will result in rapid bone growth to the area.
Intramuscular injections, such as most immunizations, canalso cause trouble. Dental work should be performed with extra care, avoidinginjections 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 increasethe chances of flare-ups and complications for both mother and baby.
Special shoes, braces, and other devices can help thepatients in lifting up weight and walking. They can also contact physicians whocan help them get special devices or tools to assist them in daily activities.
Genetic counseling can help families with the inheritanceof FOP. Another treatment is symptomatic and supportive.