Kabuki syndrome is a rare congenital disorder, which leads to the appearance of numerous anomalies and developmental delays. In the medical field, this condition is also known as Kabuki makeup syndrome or Niikawa-Kuroki syndrome. This syndrome affects one in thirty-two births, having been described for the first time in 1981, by two Japanese scientists (Niikawa and Kuroki, hence the other name of the syndrome). The reason why it is called Kabuki is related to the facial features that resemble the makeup that is used in Kabuki, a form of traditional Japanese theater.
These are the features of Kabuki syndrome:
- Characteristic facial appearance, with long eyelids and elongated palpebral fissures
- The eyebrows are arched and broad
- The lateral third of the lower eyelid is turned up
- The nasal tip is broad and depressed
- The earlobes are large and prominent or the ears are cupped
- The palate is either high-arched or the child presents a cleft palate
- Deformation of the spine, leading to scoliosis (abnormal curvature of the spine)
- The fifth finger is smaller in size
- Fetal finger pads are persistent
- Strabismus might be present at the level of the eyes
- The teeth may be widely spaced
- Hypodontia can be encountered in certain children, as a feature of the syndrome
Is Kabuki syndrome hereditary?
Kabuki syndrome is an autosomal dominant disorder, which means that, if one inherits the mutated gene from one of the parents, he/she can suffer from the actual disease.
These are the most common symptoms of Kabuki syndrome:
- Characteristic facial features (see above)
- Developmental delay with intellectual disability (mild to severe)
- Small head size (microcephaly)
- Weak muscle tone (hypotonia)
- Rapid, involuntary movements at the level of the eye (nystagmus)
- Weak muscles at the level of the eyes (strabismus)
- Short stature
- Skeletal abnormalities – scoliosis (abnormal curvature of the spine)
- The fifth finger is shorter in size
- Hip and knee joint problems
- Cleft or high-arched palate
- Dental problems (hypodontia)
- Fetal finger pads are persistent
- Heart abnormalities (congenital heart defects)
- Frequent ear infections (otitis media)
- Hearing loss
- Early puberty
- Genitourinary abnormalities
- Gastrointestinal abnormalities – anal atresia, ptosis and strabismus
- Increased susceptibility to infections or autoimmune disorders
- Endocrinologic abnormalities
What Causes Kabuki Syndrome?
The Kabuki syndrome is, as it was already mentioned, an autosomal dominant disorder. Its primary cause is a genetic mutation, hundreds of genetic mutations being identified in patients diagnosed with the Kabuki syndrome. There are also de novo mutations, meaning that the parents do not present the respective gene. There are patients diagnosed with the Kabuki syndrome who do not present a genetic mutation, which is suggestive that further research is necessary before the exact causes of this condition can be identified.
At the moment, it is known that if a parent has the respective gene, the children has a 50% chance of being born with the Kabuki syndrome. The prenatal diagnosis for the pregnancies that present an increased risk is essential.
Unfortunately, there are not many treatments available for Kabuki syndrome, given the fact that a lot of research is still necessary in relation to this condition. In order to be able to recommend the best treatment approach, the condition has to be diagnosed first and foremost. Psychotherapy might help the parents deal with the condition of the child. Genetic counseling has recently started to become more and more recommended, being considered a preventative treatment. Parents are informed about the possibility of the Kabuki syndrome being inherited, due to the genetic mutations that are carried from one generation to the other.
The condition can be rather managed than treated. These are the most common measures taken for the management of the Kabuki syndrome:
- Regular measuring of the growth (growth chart), plus of the height, weight and head circumference
- Administration of hormonal supplements (in case of hormonal deficiencies)
- Assessment of developmental milestones
- Physical therapy – recommended in particular for children who suffer from low muscle tone or abnormal curvature of the spine (scoliosis)
- Anti-seizure medication – the medication is recommended by the neurologist, having the purpose of reducing the duration and the frequency of the seizures (anti-epileptic treatment)
- Surgical intervention in case of congenital heart defects (followed by constant heart monitoring); prophylactic antibiotic treatment is recommended after the surgical intervention on the heart, so as to reduce the risk of secondary bacterial infections
- ORL intervention in case of cleft or high-arched palate
- Surgical intervention in case of congenital dislocation of the hip (casting)
- Immunoglobulins in case of immune deficiency (intravenous immunoglobulin infusions)
- Reduction of gastrointestinal symptoms by correct positioning after meals
- In case of severe feeding difficulties – placement of gastrostomy tube placement
- Special education – recommended for children with developmental disabilities
- Hearing devices might compensate for the hearing loss
- Dental intervention for hypodontia (prophylactic antibiotics are administered as well)
There are no current studies to demonstrate the reduced life expectancy in people who have been diagnosed with the Kabuki syndrome. However, there are studies that have shown problems related to childhood obesity, leading to cardiovascular risk and diabetes (which may in turn have an impact over the life span). Weight management is important, so as not to have a negative effect on the life expectancy. Medical intervention can also reduce the risks associated with this condition, guaranteeing a normal life span for the individuals who are suffering from this syndrome. Kabuki syndrome is rarely associated with complications, so there are very few risks that can have a negative impact on the life span.
In conclusion, it is highly important that this syndrome is diagnosed as soon as it is possible. In this way, the doctors can recommend the proper treatment approaches, including the necessary surgical interventions and adaptive devices that might be necessary. The earlier the correct diagnosis will be made, the more reduced the impact of the developmental disability is going to be. Apart from that, it is for the best that the child’s development is monitored on a regular basis, with each milestone being carefully checked. The regular assessment will also allow for the identification of developmental delays and guide the parents towards special education.