What Causes Costello Syndrome & How is it Treated? | Symptoms and Diagnosis of Costello Syndrome

What is Costello Syndrome?

Costello Syndrome is a rare genetic abnormality which affects multiple vital organs of the body. Costello Syndrome causes delays in growth of the child as seen by short stature along with loose skin around the neck, palms, fingers, and soles of the feet. There is also growth of noncancerous tumors in the facial and the anal area. A child with Costello Syndrome will have significant delays in achieving developmental milestones and often at times have intellectual limitations.[1]

People with Costello Syndrome go on to have characteristic facial features and extremely hard skin on the hands and feet. Their joints are also extremely flexible. People with this condition also have limited cognitive ability with also incidences of cardiomyopathy.[1]

Some of the other characteristic features of people with Costello Syndrome include abnormally large head, abnormally thick lips, and wide nostrils. People with Costello Syndrome are always at an increased risk for developing cancer. The gene responsible for causing Costello Syndrome is the HRAS gene and this is an autosomal dominant trait.[1]

What Causes Costello Syndrome?

As stated, Costello Syndrome is caused by mutations in the HRAS gene. The function of this gene is to make proteins responsible for cell division and growth. This abnormal mutation of the HRAS gene results in the cells to grow and divide continuously whether or not the gene instructs them to do so. This results in the development of both benign and malignant tumors.[2]

The abnormal mutation of the HRAS gene also interferes with the production of the elastic fibers in the tissues of the body. These elastic fibers are necessary for normal functioning of various vital organs of the body like the lungs. They are also important to keep the skin supple and also play an important role in the functioning of large blood vessels like the aorta.[2]

As stated, Costello Syndrome is an autosomal dominant condition meaning that only one copy of the defective gene is enough for an individual to get this condition. However, majority of the cases of Costello Syndrome involve new mutations and occur in people who have no family history of such condition.[2]

What are the Symptoms of Costello Syndrome?

Majority of the symptoms of Costello Syndrome can be visualized at the time of birth but in some cases they start to appear as the child grows. There is no effect on the birth weight of a child affected with Costello Syndrome but there is definitely a developmental delay compared to other children of the same age.[2]

Other symptoms of Costello Syndrome include short stature. The child will have significant limitations in intellectual ability. Children with Costello Syndrome will have significant delay in reaching their developmental milestones.[2]

As infants, it will be quite difficult to feed them. They have an abnormally large head and their skin is extremely loose, specifically around the neck, palms of the hands, and soles of the feet. They have low set ears and hyperextensibility of the joints. Abnormal heart rhythm is also one of the features of people with Costello Syndrome.[2]

How is Costello Syndrome Diagnosed?

Costello Syndrome is so rare that not many physicians would even suspect that to be the cause of the symptoms at the first visit. However, to arrive at a diagnosis, the history of the child will be taken in terms of birth weight and check the size of the head. If the physician suspects Costello Syndrome at play then a molecular testing will be ordered to check for the mutation of the HRAS gene. The test will verify whether the patient does indeed have Costello Syndrome.[2]

How is Costello Syndrome Treated?

As of now, there is no cure for Costello Syndrome and treatment is completely symptomatic and aimed at correcting some of the correctible deformities. Treatment is also given for abnormalities of the heart like cardiomyopathy. Aside from that, some of the ways to help manage Costello Syndrome include trying to help a child deal with feeding problems. Children with Costello Syndrome require special education due to their limited cognitive ability. They also require physical therapy for hyperextensible joints.[2]

Since patients with this condition often have a loose Achilles tendon, this can be tightened surgically. Papillomas that develop due to Costello Syndrome can be treated with cryotherapy. There is very limited data as to the prognosis or life expectancy of a person with Costello Syndrome. However, some data suggests that fatality generally occurs due to a complication associated with this condition, specifically cardiovascular problems.[2]

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