Re: Any information on Ectodermal Dysplasia?

Well Regina, your question "What is Ectodermal hyperplasia"? certainly posed a problem for me. After exhaustive searches on the web using the most powerful search engines no information was to be found . I tried to go to the site you referred to (www.nfed.com), but that too drew a blank, no URL at that server.

I am thinking that perhaps you might have meant Ectodermal Dysplasia not hyperplasia. I have taken the liberty of including the information on ED in the hopes that maybe this is what you are really looking for. If this is not correct please feel free to resubmit and perhaps supply me with a little more information from the web site you were able to access.

Ectodermal Dysplasia

WHAT IS AN ECTODERMAL STRUCTURE?

Before the developing baby is large enough to be seen, a layer of cells covers the outside of the body. This surface layer of cells is called the ectoderm, and from it develop the skin, hair, nails, teeth, nerve cells, sweat glands, parts of the eye and ear and parts of some other organs (see Figure 1). Each of the listed parts of the body, then, is called an ectodermal structure. There are many disorders that involve only one of these structures and are not properly called ED. Any combination of defects involving more than one of these structures, however, should be called ED; the list of such combinations is extensive. For example, one person may have missing teeth and defective nails, while another may have missing teeth, inability to sweat and sparse hair. Still another may have sparse hair and a hearing loss. Each combination of defects represents another type of ED and has a specific name.

WHAT CAUSES ECTODERMAL DYSPLASIA?

Ectodermal Dysplasia is caused by a single abnormal gene or pair of abnormal genes. The chance for parents to have an affected child depends on the type of ED that exists in the family. In some families the mistake in the gene was a fresh mistake (mutation) in their child and the likelihood of another child being affected is very low. There are other families however that have an inherited form of ED with recurrence risk ranging from 25% to 50%.

SWEAT FUNCTION

Diminished or absent sweating is a common problem. The sweat glands are absent, reduced in number, or may not function normally. Reduced sweating may result in very high fevers, because the body regulates its temperature by sweating. Often, the first clue that the sweat glands are absent or are not functioning normally is an elevated temperature.

Elevations in body temperature are often caused by high environmental temperatures, excessive activity, or heavy clothing. When the body temperature is elevated, the skin feels dry, hot and may be flushed or pale.

HAIR

The scalp hair is absent, sparse, fine, lightly pigmented, or abnormal in texture. The hair may also be fragile and unruly, sticking out in all directions and difficult to comb. The hair is dry because the oil glands are absent or poorly developed.

Some defects of the hair are evident at birth, while others are not noted until later in life. Hair growth is slow and haircuts are not often needed. After puberty hair growth improves in some persons.

The eyebrows, eyelashes, and other body hair may also be absent or sparse, but beard growth in males is usually normal.

NAILS

Most people with ED do not have nail abnormalities, although the nails are frequently dry and rough. A distinctive finding in one of the forms of ED is a short nail that fails to grow to the end of the finger. In others, the nails may be thin and fragile, thick and distorted, or brittle and slow- growing. Nails with any of the listed abnormalities may be prone to infection.

TEETH

The teeth are missing altogether or reduced in number. Teeth that are present are widely spaced, tapered, or malformed. In persons with some types of ED, the enamel (outer layer of the teeth) is defective and there may be an excessive number of cavities. When teeth are missing the jawbones in which they are ordinarily embedded do not develop well, leading to a typical aged appearance in the face.

EAR, NOSE AND THROAT

The generalised underproduction of body fluids leads to several problems. Saliva is sparse, causing problems with chewing, tasting, and swallowing foods. The mucous secretions of the nose are excessively thick, forming a crusty mass. Nasal infections are common. A hoarse, raspy voice is common. Abnormal ear wax production may be noticed in some people with ED. The most frequent problem is accumulation of wax in the ear canal. Hearing loss may occur secondary to impacted wax or to nerve degeneration.

EYES

Tears are reduced, causing irritation of the eyes, conjunctivitis, and sensitivity to sunlight. There may be cloudy corneas or cataracts.

RESPIRATORY PROBLEMS

The linings of the nose, larynx, trachea and lungs are moistened by various glands, some of which may be defective in ED. Respiratory problems are therefore common.