Waardenburg syndrome is a genetic disorder characterized by problems that can include depigmentation lesions ( albinism ) of the skin, eyes, and hair, congenital (birth) deafness, and the specific structure and position of the eyes and nose.
This syndrome affects both men and women, as well as people of all ethnic backgrounds. This disease is believed to account for 2% to 5% of all cases of congenital deafness. This is estimated to occur in 1 in 40,000 people .
Symptoms and types
Waardenburg syndrome is divided into four types based on the physical manifestations of the condition. People with type 1 Waardenburg syndrome are considered to have 2 main criteria, or 1 major criterion plus 2 minor criteria. Waardenburg syndrome type 2 is defined by having all the characteristics of type 1, with the exception of cantorial dystopia .
- Deaf or hard of hearing from birth
- Pale blue eyes or eyes of two different colors.
- Loss of hair color or a white section of hair on the forehead.
- At least one close relative with Waardenburg syndrome
- Canthorum dystopia: the inner corner of the eye shifts to one side.
- Clear or white skin patches (leukoderma)
- The eyebrows move towards the middle of the face.
- Nose abnormalities
- Premature graying of hair (at age 30)
Waardenburg syndrome type 3 or Klein-Waardenburg syndrome is similar to type 1, but affects skeletal muscle, which can include contractures or underdeveloped muscles. Waardenburg syndrome type 4 or Waardenburg-Schach syndrome is also similar to type 2, but includes Hirschsprung 's disease (a malformation of the gastrointestinal tract) .
Babies born with Waardenburg syndrome may have hearing loss and may show distinctive features of their skin and hair. However, if symptoms are mild, Waardenburg syndrome may not be diagnosed unless another family member is diagnosed and all family members are tested .
Formal hearing tests can be used to evaluate hearing loss. If gastrointestinal symptoms are present, imaging tests (eg, abdominal CT) or interventional tests (eg, endoscopy ) may be required.
Even within the same family, Waardenburg syndrome can affect people in different ways. Some people may not need treatment, while others may need physical therapy, treatment for hearing deficits, additional skin protection to avoid sunburn, or surgery. Waardenburg syndrome generally does not cause cognitive (thinking and learning) problems, mood, or mental effects.
In types 1 and 2, Waardenburg syndrome is inherited in an autosomal dominant pattern, which means that the affected person has a 50% chance of having a sick child with each pregnancy. Types 3 and 4 can be inherited in a more complex way .
Several genes associated with this condition have been identified, including mutations in the EDN3, EDNRB, MITF, PAX3, and SOX10 genes .
Because symptoms can vary, it is impossible to predict whether a sick child will have milder or more severe symptoms than their parents, but genetic counseling can help assess the risk of passing Waardenburg syndrome to the child.