What is Ectodermal Dysplasia?

Ectodermal dysplasia (ED) is a term used to classify a group of inherited or genetic disorders that mainly affect the hair, skin, teeth, nails, and glands underneath the skin (e.g. sweat glands, sebaceous glands).^1,2 Other parts/organs of the body that also grow from the ectodermal and the mesodermal embryonic layer (2 out of 3 stem cell layers from which our entire body develops inside the womb) may also be affected by it.^2,3 It is known to affect approximately 7 per 10,000 births internationally with a higher prevalence in those assigned male at birth (AMAB).^2,3

It is passed down from parents to offspring via genetic mutations which are highly variable in both their cause and effect.² There is no cure for it but when diagnosed early it can be managed with most individuals having a normal life expectancy.² 

Overview

Ectodermal dysplasia is a broad umbrella term that is used for a group of inherited genetic disorders that primarily affect the hair, skin, teeth, nails and glands underneath the skin (e.g., sweat glands, sebaceous glands).^1,2 Cases have also been reported where ectodermal dysplasias in addition to primary organs affect the mammary glands(breasts), nervous system, ears, eyes and tear glands, pituitary and adrenal glands. Some cases also report the involvement of the skin and glands inside the nose, throat (causing hoarseness/ loss of voice) and around the anus.^2,3

It is a congenital defect, meaning it has been present since birth.^1,3 It is passed down from parents to offspring via genetic mutation which may be inherited or spontaneous.^1,3 This mutation affects the normal development of the specific stem cell layers (ectoderm and mesoderm) which results in impaired development of the various parts of the body that develop from it (e.g. hair, skin, teeth).³ It has been reported more commonly amongst Caucasian races as compared to other races.¹

Understanding ectodermal dysplasias

To understand Ectodermal Dysplasia, it is important first to understand its cause which is a genetic mutation which affects stem cells (ectoderm and mesoderm germ layers) and impairs the development of parts of the body or organs that are formed from those cells.^1,3 To make this simpler think of this as unsound raw material used to manufacture a product which will eventually not be able to function similarly to the same product made from raw materials of an appropriate built.

Given the huge variation in the cause (genetic mutation) and the effects (symptoms) stemming from different types of mutations, there are currently around 150 different types of disorders grouped under the term ectodermal dysplasias.⁴ To classify them, the following groups have been created:^3,4

1. ED1: Trichodysplasia (abnormal or impaired hair growth)
2. ED2: Dental dysplasia (abnormal or impaired growth of teeth)
3. ED3: Onychodysplasia (abnormal or impaired nail growth)
4. ED4: Dyshidrosis (abnormal or impaired growth of sweat glands)

Matching symptoms/clinical manifestations commonly noted with the groups above, the 150 different types of Ectodermal Dysplasia (ED) are further classified into 11 subgroups.^3,4 

Given the genetic risk, prenatal screening for ectodermal dysplasia is available, for further discussion around this we advise you to contact your GP surgery or treating clinician.

Clinical presentation

The individual manifestations of each subgroup and type of ectodermal dysplasia are highly variable, but it typically affects 4 common areas which may be primarily involved in the following ways:^1,6

Hair

• Body and scalp hair may be absent or sparse, thin and lighter in colour
• More coarse, highly brittle, curly or possibly twisted
• Hair follicles or bulbs may be distorted, small and split(bifid)
• Eyebrows are also typically affected and may be thin and sparse

Nails

• Are thicker, abnormally shaped, ridged, discoloured, slower-growing and/or brittle
• Can get repeatedly infected
• May also be absent in some cases 

Teeth

• Teeth may grow in unusual shapes and sizes (peg-shaped or pointed) due to their impaired development⁵
• May also be missing completely (anodontia) or fewer in number (hypodontia & oligodontia)⁵
• Enamel (outermost layer of the tooth) is defective
• Are prone to easily developing dental infections
• Delayed eruption of teeth

Sweat glands

• May be completely absent or sparse such that their functioning is abnormal or completely absent
• Due to their absence normal body temperature regulation is impaired and can cause hyperthermia in individuals with ectodermal dysplasia quite easily, especially in warmer climates
• Fever that keeps reoccurring in children may lead to seizures and other neurological problems

Some other signs and symptoms also noted in ectodermal dysplasia are:^1,6

• Skin may be lightly or differently pigmented (red or brown). It may be thick over the palms and soles and may be more prone to bleeding, cracking and repeated infections
• Dry skin that is more prone to rashes and infections
• Impaired functioning of the lacrimal gland (tear) can cause dry eyes. Cataracts and other visual defects may also occur later in life
• Hearing problems due to impaired ear development
• Cleft lip and palate
• Missing toes and fingers
• Lack of protective secretions such as mucous glands in the respiratory tract may cause repeated respiratory infections
• Foul smelling nasal discharge from chronic nasal infections
• Impaired breast development
• Impaired salivary gland development can cause abnormal functioning of the same and dryer mouths
• Short stature
• Photophobia (fear of light) may be noted in some individuals
• Hypohidrotic ectodermal dysplasia, the most common form of ED is characterised by a typical fascial pattern that includes frontal bossing; sunken cheeks; saddle nose; thick, everted lips; wrinkled, hyperpigmented skin around the eyes; and large, low-set ears

If you do wish to read further about this, check out this patient information leaflet and we hope you find it helpful.

Diagnosis

There is no standard established checklist or criteria for diagnosis of ectodermal dysplasia, given the high amount of variation in symptoms amongst different types. Diagnosis is typically by history and physical examination to identify symptoms associated with at least 2 or more of the above-mentioned 4 most commonly affected organs.^1,4,7 Thus diagnosis may be established by a geneticist, dermatologist or a dentist or may need a multispeciality team approach.

Other methods to diagnose ectodermal dysplasia that have been tried include detailed studies around the characteristics of hair, dermatoglyphic (fingerprint) analyses, analysing lacrimal secretions (tears), sweat pore analysis using starch-iodine powder, pilocarpine iontophoresis, and analysing patterns of scalp hair.^1,7

A genetic evaluation performed by a relevantly qualified professional is often also helpful in determining if the condition is isolated or part of any other condition or syndrome.⁷

Laboratory investigations such as additional blood tests (immunoglobulin levels, T-cell subset populations) may also be ordered by your clinician.^1,7 In some cases a skin biopsy and microscopic examination may also be needed for diagnosis.¹

Diagnosing ectodermal dysplasia in early infancy is difficult since manifestations involving teeth, hair and the ability to sweat are harder to detect.¹ Nonetheless, most children with severe variants may be diagnosed at birth, while milder forms may go undetected until symptoms begin to affect the child’s daily life or development.¹

Prenatal diagnosis for ectodermal dysplasia is available and more information on it can be found here. For more specific information we recommend asking your GP surgery or treating clinician about this.

Treatment and management

Given the origin of ectodermal dysplasia and the clinical manifestations which affect different parts of the body differently, the management is also strictly dependent on individual presentation. It is however important to note here that ectodermal dysplasia cannot be treated and there is currently no cure for it.^1,3,8 Future research in prenatal treatments may hold better promise.⁹

Following are some options for managing clinical manifestations:

Temperature monitoring and maintenance

Hyperthermia due to the absence of sweat glands especially in children is a severe complication and thus strict monitoring of body temperature must be done for individuals with this sub-type of ectodermal dysplasia at all times.^1,7

Heat-generating activities especially in older children, must be tackled with physical measures to cool down such as frequent drinking of cold liquids, and wearing special cooling vests or caps.^1,7 

Teeth

Dental management in patients with ectodermal dysplasia may require multispeciality expertise for better functioning and cosmetic outcomes. Various dental treatments such as restoration to treat dental infections, fixed or removable dentures, and implants may be needed in patients with ectodermal dysplasia. The majority of individuals need to wear dentures throughout their lifetime.⁸

Hair

Most of the hair care is directed towards preventing further damage to hair shafts. Gentle shampoos (e.g. Neutogena), mild dandruff shampoos, cream rinses etc. may be helpful in management. Further information about this can be found here. Patients may require cosmetic solutions as well such as wigs, hair transplants etc.^1,7 

Skin

Skin manifestations are also variable but in most cases, emollients or moisturisers are helpful for dry skin-like conditions. For oozing erosion and chronic erosive scalp dermatitis, more aggressive wound care with topical or systemic antibiotics may be required.¹ More specific information about this can be found here.

Nails

Individuals with ectodermal dysplasia are prone to recurrent nail bed infections, thus constant care and grooming of nails may be required in most cases.

As discussed in clinical presentations there might be additional secondary presentations in ectodermal dysplasia which may require support from different specialities such as ophthalmology, ear nose throat specialists and hence treatment plans will need to be tailored according to need.

While management may provide comfort from symptoms, individuals with Ectodermal Dysplasia may also require mental health and further support, for more information about this you can read here or alternately speak to your local GP surgery or treating clinician.

Complications and prognosis

Some common complications arising from ectodermal dysplasias are hyperthermia, asthma, recurrent upper respiratory tract infections, lasting dermatitis, scarring alopecia (balding), dental caries, and difficulty in eating/feeding. Most of these are manageable and with appropriate care may not be life threatening.^1,3,4,8 Some severe complications may be mental or physical growth retardation, visual disturbances, early renal failure due to abnormalities in the genitourinary tract, morbidity and mortality due to recurrent skin and respiratory infections caused by impaired immune systems.¹

Most of these complications can be managed and most individuals diagnosed lead productive and full lives as they understand how to manage their condition. Life expectancy in most individuals with ectodermal dysplasia is normal, with minimal impairment to quality of life.^1,8

FAQs

What are the causes and risk factors of Ectodermal Dysplasia?

It is genetic in origin and is passed down from parents to offspring with a higher prevalence in assigned males at birth. Genetic mutations may also be spontaneous. Risk factors include known family history of ectodermal dysplasia and Caucasian inheritance.^1,8

Is there a cure for Ectodermal Dysplasia?

Since it is genetic in origin, there is no cure for it, although future research into it may show some promise.⁹ Currently, with appropriate treatment and management, most individuals tend to live with minimal disruption to their quality of life and with normal life expectancy.^1,8

What are some common signs and symptoms of Ectodermal Dysplasia?

Examples of some signs and symptoms are sparse or complete absence of hair, dry & scaly skin, lower number or absence of teeth and impaired growth of nails. To read more about see our section on clinical presentations.

Summary

Ectodermal dysplasia (ED) is a term used to classify a group of inherited or genetic disorders that mainly affect the hair, skin (internally and externally), teeth, nails, and glands underneath the skin (e.g. sweat glands, sebaceous glands).^1,2 Other parts/organs of the body mammary glands(breasts), nervous system, ears, eyes and tear glands, pituitary and adrenal glands may also be affected.² It is present since birth and is passed down via mutation in genes which may be spontaneous or inherited.^1,3 

It affects approximately 7 in every 10,000 births worldwide, with those assigned male at birth and those with Caucasian inheritance being affected by it more commonly.^1,3 Examples of some signs and symptoms are sparse or complete absence of hair, dry & scaly skin, lower number or absence of teeth and impaired growth of nails. It has no cure, but if diagnosed early, appropriate treatment and management such as dentures, gentle shampoos, frequent moisturising, maintenance of constant body temperature etc.; are useful.^2,3 
Complications of ectodermal dysplasia may be hyperthermia, recurrent respiratory infections, asthma, dermatitis, dental caries, growth retardation both mentally and physical, early & scarring balding, visual problems, early renal failure and immune compromise in later stages.² Most individuals with ED have a normal life expectancy and minimal impairment to quality of life.^1,8