Anhidrotic ectodermal dysplasia

Definition

Ectodermal dysplasia is a hereditary condition characterized by abnormal development of the skin, hair, nails, teeth, and sweat glands.

Alternative Names

Causes

There are many different types of ectodermal dysplasia. Multiple genes have been discovered that cause ectodermal dysplasias. The most common form of ectodermal dysplasia is linked to the X chromosome and usually affects men. Another form of the disease affects men and women equally.

Patients with ectodermal dysplasia may have absent or decreased sweating because of a lack of  sweat glands. Children with the disease may have difficulty controlling fevers. Mild illness may produce extremely high fevers, because their skin can't sweat and control temperature properly.

Affected adults are unable to tolerate a warm environment and require special measures to maintain a normal body temperature.

Patients may have chronic nasal infections with foul-smelling discharge and increased lung infections.

The skin is thin with light coloring. Hair may be absent or very thin. Teeth develop abnormally, and many teeth are missing.

Symptoms

• Lower-than-normal number of teeth
• Delayed or absent tooth formation
• Inability to sweat
• Absent tears (occasional)
• Thin skin
• Decreased skin pigment
• Foul-smelling nasal discharge
• Poor temperature regulation
• Heat intolerance
• Scanty hair
• Absent hair
• Abnormal nails
• Low nasal bridge

Exams and Tests

• Biopsy of the mucous membranes (indicates absent or poorly-formed mucous membranes)
• Biopsy of the skin (indicates absent or poorly-formed sweat glands)
• Genetic testing (available for some subtypes of this group of disorders)

Treatment

There is no specific treatment for this disorder. Improvements in the appearance and in function can be made with the use of wigs in the absence of scalp hair and dentures to replace missing and defective teeth. Synthetic tears may be necessary to replace normal tearing and prevent drying of the eyes. It may be helpful to spray the nostrils with saline nose spray frequently to remove debris and prevent infection.

Temperature control is a constant problem. Affected people require a cooler climate and may require frequent cooling water baths or sprays to maintain a normal body temperature. (Water evaporating from the skin replaces the cooling function of sweat evaporating from the skin.)

Outlook (Prognosis)

Having ectodermal dysplasia will not shorten your life span, but you must pay constant attention to temperature regulation and other problems you may have.

Possible Complications

• Febrile seizures  -- seizures caused by high fever
• Brain damage caused by increased body temperature

When to Contact a Medical Professional

Call for an appointment with your health care provider if your child shows symptoms of this disorder.

Prevention

Genetic counseling for prospective parents with a family history of ectodermal dysplasia is recommended. Prenatal diagnosis of ectodermal dysplasia is possible in many cases.