Kabuki syndrome (KS) is a rare condition that affects multiple parts of the body. The name comes from the facial features typical of those with the disorder. They often have high, arched eyebrows, thick eyelashes, and an elongated eye shape. In Kabuki theater, actors similarly exaggerate their facial features with makeup.
How Was Kabuki Syndrome Discovered?
In the late 1960s, two independent groups of Japanese scientists observed children with an unusual set of symptoms. After seeing more children with similar symptoms, the two groups published their findings in 1981. One doctor used the name Kabuki makeup syndrome for the disorder. The name was later shortened to Kabuki syndrome.
Scientists first thought that Kabuki syndrome occurred only in Japan, but they soon found cases in different ethnic groups all over the world. They believe it affects one in 32,000 babies.
What Is Kabuki Syndrome?
Kabuki syndrome is a genetic condition and is present at birth. Some symptoms are apparent from birth. Others may appear later. Individuals can have different mixes of symptoms.
Getting a diagnosis of a rare disease can be difficult. Because KS is rare, many doctors have never seen a case. Diagnosis can also be hard because the symptoms of different disorders overlap. The pool of literature on such rare diseases is also small.
What Are the Symptoms of Kabuki Syndrome?
Besides the unusual appearance of the eyes, other atypical Kabuki Syndrome facial features can include:
- Cupped ears
- Noses that are flattened at the tip
- Widely spaced or missing teeth
Affected people sometimes have cleft palate, vision problems, or hearing problems.
Issues with the skeleton and muscles are also common. These include:
- Heads that are unusually shaped or smaller than normal
- Spinal abnormalities
- Abnormally loose joints
- A lack of muscle tone
- Short fingers, especially the pinky fingers
An unusual symptom that often appears in KS is persistent finger pads. These are fleshy pads at the ends of the fingers that are present when a baby is in the womb. They usually disappear before birth but may be present in children with KS.
Children with KS are often below average in height, possibly because of low levels of growth hormone.
Those with KS may also have problems with organs and bodily systems, including:
- Heart defects
- Malformed kidneys
- Problems with the gastrointestinal tract
Do Those With KS Have Behavioral Issues?
Those with Kabuki syndrome often have mild or moderate intellectual disabilities. They may also experience developmental delays and sensory processing disorders. Often, their behavior is similar to patterns associated with autism or obsessive-compulsive disorder. Children with KS may show signs of anxiety or depression as they get older.
Behavioral patterns may include:
- A need to chew on items or put them in their mouths
- Strong reactions to noises and other stimuli
- An aversion to foods with certain tastes or textures
Parents of children with KS often report that they enjoy music and have a good memory for particular songs. Some also have an exceptional memory for faces or dates.
What Causes Kabuki Syndrome?
Scientists have identified two genetic mutations that can cause Kabuki syndrome. They believe that the KMT2D mutation causes about 75% of the cases. Of those who test negative for KMT2D, about 9% test positive for another mutation, KDM6A. There may be other gene mutations that cause Kabuki syndrome that scientists have not yet identified.
Researchers believe that most Kabuki syndrome cases result from new mutations in the person with KS. It is, however, also possible to inherit the syndrome from a parent. Parents can pass both the KMT2D and KDM6A mutations to their children, though the two mutations have different patterns of inheritance.
How Is Kabuki Syndrome Diagnosed?
In 2019, a group of experts agreed upon a method for diagnosing Kabuki syndrome. Individuals with a history of developmental delays or intellectual disability and poor muscle tone can undergo genetic testing. A positive genetic test results in a definite diagnosis. If they test negative for mutations but have several of the typical features of KS, they may still receive a definite diagnosis. Other combinations of symptoms can result in a probable or possible diagnosis.
How Is Kabuki Syndrome Treated?
There is no cure for Kabuki syndrome. Children do not outgrow the disorder. Over time, though, certain symptoms could get worse or better.
Kabuki syndrome treatment depends upon the physical problems that an individual has. Early diagnosis and treatment are essential. Those with KS may need the services of specialists, including:
- Dental specialists
- Hearing specialists
- Speech pathologists
Those with KS may also benefit from therapy, including:
- Speech therapy
- Physical therapy
- Occupational therapy
- Sensory integration therapy
The life expectancy of those with Kabuki syndrome is not shortened by the syndrome itself, but conditions associated with the syndrome can affect prognosis. For example, heart defects and kidney problems can cause premature death.
What Is School Like for Someone With KS?
Children with Kabuki syndrome can attend school. They will need an educational plan tailored to their needs. In the United States, they will need an IEP (Individualized Education Plan) or a 504 plan. Some children will need an instructional aide. They might attend special education classes. Some children with KS are able to also participate in sports.
What Is Adult Life Like for Someone With KS?
Those with Kabuki syndrome can have a variety of conditions ranging from mild to severe. It is difficult to predict what a child's future will look like. High-functioning individuals with KS may live independently or marry.
The Takeaway About Kabuki Syndrome
Kabuki syndrome is a rare genetic disorder that may be diagnosed soon after birth. Sometimes, it is not diagnosed until developmental delays appear. Distinctive facial features and a lack of muscle tone are important markers.
Those with Kabuki syndrome can have a wide range of physical problems. Individuals have different mixes of symptoms. There is no cure, but early intervention can make some symptoms more manageable. Those with Kabuki syndrome can live a normal life span and participate in a variety of activities.