Smith-Magenis Syndrome: Causes, Symptoms, Treatment, Prognosis

Smith-Magenis Syndrome is a type of a complicated developmental disorder which tends to affect multiple organ systems of the body. It is characterized by abnormalities that may be present at the time of birth in addition to growth and developmental delays along with behavioral and cognitive problems.

Children with Smith-Magenis Syndrome will also have distinct facial features and musculoskeletal abnormalities. Children with Smith-Magenis Syndrome will also exhibit intellectual disability with delay in attaining motor skills.

They also tend to have problems with speech, and the most disturbing of all a self injurious behavior which may be potentially very dangerous and hence children require constant monitoring when they are dealing with Smith-Magenis Syndrome. The symptoms are quite variable and differ from individual to individual. The main cause of Smith-Magenis Syndrome is mutation of the RAI1 gene.

As stated, the main cause of Smith-Magenis Syndrome is a missing short arm of chromosome 17. This constitutes for about 90% of the cases of Smith-Magenis Syndrome. This missing portion of the chromosome contains the RAI1 gene which is responsible for growth and development of an individual. The main reason for the chromosome that is missing or deleted is not yet known but in maximum cases this is spontaneous and is not related to any other cause. This missing short head of chromosome 12 and the subsequent mutation of the RAI1 gene is the main cause of Smith-Magenis Syndrome.

The main symptoms of Smith-Magenis Syndrome are distinct facial features, certain skeletal malformations, variable intellectual disability, delay in speech and attaining motor skills, inability to sleep adequately, tendency towards self harm and other attention seeking behaviors.

It is not necessary that all the above symptoms will be present in every individual with Smith-Magenis Syndrome. The symptoms are highly variable where in some cases very mild symptoms may be present whereas in severe cases most of the symptoms may be present. The symptoms may even vary from individual to individual of the same family affected with Smith-Magenis Syndrome.

The characteristic symptom and the physical features that the patient presents with is a virtual give way of a genetic condition at play here. This is further confirmed by taking a detailed history of the patient to determine if any other family member has the same symptoms.

A detailed clinical evaluation may also be performed to look at the various physical defects that the patient may be having because of Smith-Magenis Syndrome.

In order to confirm the diagnosis, certain specialized test may have to be conducted. These specialized tests will include an enzyme assay in which there will be clear indication of mutation of RAI1 gene confirming the diagnosis of Smith-Magenis Syndrome.

Additionally, a genetic study will also be done which will also show missing or deleted short arm of chromosome 17. Both these findings will confirm the diagnosis of Smith-Magenis Syndrome.

The treatment for Smith-Magenis Syndrome requires a multidisciplinary effort from a team of specialists which will include pediatricians, neurologists, speech and language specialists, psychiatrists and psychologists, who will work together and formulate a treatment plan for the patient.

Genetic counseling may also be of benefit for the patient and the family and will help in the course of treatment. Other than supportive and symptomatic, there is no other clear cut treatment for Smith-Magenis Syndrome. Early diagnosis and treatment is essential for the child to be as independent as possible.

Smith-Magenis Syndrome child will require special education with speech and language therapy, physical therapy and occupational therapy for making the child independent. Sensory integration therapy will also be of benefit in children with Smith-Magenis Syndrome to allow them to respond better to stimulus which is extremely poor in cases of Smith-Magenis Syndrome.

To treat behavioral and attention seeking problems in children with Smith-Magenis Syndrome, medications may be used. For difficulties in feeding, consultation with a GI specialist in coordination with the pediatrician will be of great value in treatment of Smith-Magenis Syndrome. To control seizures, again anticonvulsants are available which will help control seizures in patients with Smith-Magenis Syndrome.

It is very difficult to judge the actual prognosis of a condition like Smith-Magenis Syndrome due to the variability of the symptoms and the response of the patient towards treatment which is highly supportive and symptomatic.

Some individuals with this condition have grown up to become gainfully employed to some degree and live somewhat independently but not fully independent where as some individuals are completely disabled and require constant supervision of their parents or nursing care staff as they cannot live at home if proper support system is not present at home for people suffering from Smith-Magenis Syndrome.