A-Z of syndromes: Joubert syndrome
How to recognise and support children who have this rare neurological condition
Named after the French doctor who first described this rare neurological condition, Joubert syndrome is characterised by developmental delay, hypotonia, ataxia and oculomotor apraxia.
It usually occurs because of an autosomal recessive trait resulting in a genetic abnormality affecting some genes. This means that, although neither parent shows signs of being affected, they carry the abnormal genetic trait and there is a 25% risk with each pregnancy of having an infant with the syndrome. They can also have children who do not have the syndrome, but carry the affected gene. It occurs in all races and both genders but is more common in isolated communities, where the gene pool may be less diverse.
The genetic abnormality is responsible for the under development of important areas of the brain such as the vermis and the brainstem. The cerebellar vermis is responsible for controlling movement and the brainstem maintains the infant’s involuntary functions, such as heartbeat, breathing and thermoregulation.
There is a trajectory of severity. Some infants will die before a diagnosis, others will grow to become individuals who can live independent, fulfilling lives. Most children will fall somewhere in the middle. The most severely affected may be recognised by their parents soon after birth, for example if they have limbs that are hypotonic this may be identified early in the neonatal period.
Infants with more moderate forms of the condition may not develop control of their bodies, but this may not be identified until they have difficulties rolling over, sitting, standing, walking or maintaining their balance.
Joubert syndrome can become a life-threatening condition as a lack of respiratory drive can cause apnoea and other breathing problems and the infant may need to be ventilated. Sometimes this may improve with age but, if persistent, can threaten survival and create ethical dilemmas about whether it is in the best interest of the child to prolong invasive treatment.
An infant with Joubert syndrome may have the characteristic appearance of a large head, along face with a prominent forehead and high rounded eyebrows over slanted eyes. There may be abnormal eye movements including a squint, retinal degeneration and congenital blindness.
Other features may include low set ears, a broad nasal ridge, an upturned nose and a protruding tongue. These facial features can diminish as the child grows. In those that survive infancy their cognitive and physical development can be delayed and there may be moderate-to-severe learning disabilities.
Treatment and support
Treatment options depend on the severity of the condition. Families will need access to a full range of support services to maximise their child’s potential and carers have a heavy physical and emotional burden which should be recognised.
Following a normal vaginal delivery paediatricians were asked to review Elouise as her mother and the midwives were concerned about her body tone and her head lag. The doctor also identified some facial characteristics and wondered if this could be related to a syndrome.
His suspicions were strengthened when he learned that both parents had originally come from a small, isolated island community.
Elouise was a healthy but quiet baby, she was slow to smile, engage in finger play, roll over and sit independently. Physiotherapy assessments were initially undertaken every three months and she attended swimming lessons. When Elouise finally walked, her gait was ataxic and poorly coordinated. Speech and language therapy was provided and it was clear that the family understood more of Elouise’s speech than could be identified by strangers.
As this is a rare syndrome there are few precedents for what the future may hold. Education, social care and child health professionals are involved with the family and, although it can be frustrating for the family at times, they have good relationships with those involved.
About the authors
Doreen Crawford is nurse adviser with the consultancy Crawford McKenzie and Annette Dearmun is divisional head of nursing and clinical governance, Oxford University Hospitals NHS Trust