What is Joubert Syndrome?
Joubert Syndrome is an extremely rare pathological condition of the brain in which there is underdevelopment of the cerebellar vermis and the brainstem. The cerebellar vermis controls the balance and coordination of the body whereas the brainstem controls the vital functions of the body like swallowing, breathing etc. A child with Joubert Syndrome will present with an abnormally fast breathing, will have hypotonia, abnormal eye movements, delayed development and ataxia. There will also be certain visible physical deformities like extra fingers or toes, cleft lip or palate, and tongue abnormalities. The child may also have bouts of seizures.
Majority of cases of Joubert Syndrome are inherited and this disease is inherited in an autosomal recessive form which means that a copy of the defective gene causing this condition should be inherited from each parent in order to get this disease. Studies have shown that there are at least 10 genes which may result in the development of Joubert Syndrome of which the most common are NPHP1, AHI1, and CEP290.
What Causes Joubert Syndrome?
As stated above, Joubert Syndrome is caused due to faulty genes as a result of which there is underdevelopment of the cerebellar vermis and the brainstem which results in impairment in the functions that these structures perform which are posture and muscle control, control of heartbeat, and temperature control. There have been at least 10 genes that have identified to be responsible for causing Joubert Syndrome of which the most common are NPHP1, AHI1, and CEP290 genes.
What are the Symptoms of Joubert Syndrome?
The symptoms of Joubert's Syndrome are quite variable and can range from very mild to extremely severe depending on the extent of the disease. Children with Joubert's Syndrome will have the following:
- An abnormally large head with a prominent forehead and a broad nose, and they will have a tendency to keep their mouths open with the tongue protruding out
- There will be hypotonia with unsteadiness
- There will be developmental delays and the child will find it tough to reach his or her developmental milestones
- There will be jerky eye movements and some children will have difficulty in moving their eyes
- Majority of the children with Joubert's Syndrome will have some form of learning disability with behavioral problems
- Epilepsy has also been noted in some children with Joubert's Syndrome
- In some children, there will be development of renal cysts affecting the kidney function
- The classic presentation feature of Joubert's Syndrome is the rapid breathing pattern that can be noticed immediately after birth of the child.
It should be noted here that all these symptoms, except the rapid breathing are a part of the brain malfunction and is not a part of the disease process and hence these abnormalities have a potential to improve over time.
How is Joubert Syndrome Diagnosed?
In case if Joubert's Syndrome is suspected in a child, then the best way to diagnose is with an MRI scan of the brain which will clearly show an underdeveloped cerebellar vermis and brainstem which will potentially confirm the diagnosis of Joubert's Syndrome.
How is Joubert Syndrome Treated?
The treatment for Joubert's syndrome is basically symptomatic and supportive. The developmental delays shown by the child can be treated with physical and occupational therapy to make the child somewhat independent and be able to put his or her thoughts across. The epilepsy due to Joubert's Syndrome can be treated with anticonvulsants. Treating a child with Joubert's Syndrome involves a concentric effort from multiple specialties like nephrologists, ophthalmologists, geneticists and neurologists. Liver and kidney function will have to be checked on a regular basis to see whether they are functioning normally. As stated above, some of the abnormalities due to Joubert's Syndrome like developmental delays and problems with learning and behavioral problems tend to get better as the child grows and with appropriate therapy despite the ongoing disease process of Joubert's Syndrome.
What is the Prognosis of Joubert Syndrome?
The prognosis for children with Joubert's Syndrome depends on whether the cerebellar vermis and the brainstem is partially developed or is entirely absent and also the extent and severity of the symptoms. In case of children who develop complications due to breathing problems due to Joubert's Syndrome then the prognosis is not all that good but if hat aspect of the disease is controlled then the prognosis is quite a bit better. Children with mild forms of this disorder will have minimal motor disability and good mental development while children with severe form may have severe motor disability, impaired mental development, and problems with functioning of various vital organs of the body due to Joubert's Syndrome.