Ectodermal DysplasiaReported by: Eguillion, Monica C.1ECTODERMALGreek word ektos meaning "outside" derma, meaning "skin."
Dysplasia is a term used in pathology to refer to an abnormality of development. is characterized by defective formation of one or more structures derived from ectoderm. is describe a heterogeneous group of rare, inherited disorders mainly characterized by dysplasia of ectodermal tissues and occasionally of mesodermal tissues of the developing embryo. ED is characterized by the triad of signs comprising of atrichosis or hypotrichosis, abnormal anodontia or hypodontia and inability to sweat due to lack of anhidrosis or hypohidrosis. In addition, nail dystrophy and palmoplantar hyperkeratosis is usually present. The sensorineural and adrenal tissues are also affected at various degrees.NATUREThere are 2 major types of this condition depending on the number and functionality of the sweat glands: X-linked anhidrotic or hypohidrotic, where sweat glands are either absent or significantly reduced in number (Christ-Siemens-Touraine syndrome), and hidrotic, where sweat glands are normal and the condition is inherited as autosomal dominant (Cloustons syndrome). The dentition and hair are affected similarly in both types, but the hereditary patterns and nail and sweat gland manifestations tend to differ.
Mode of InheritanceHED may be inherited in one of three patterns: X-linked recessive, autosomal recessive and autosomal dominant. Ninety-five percent of randomly selected individuals with HED have the X-linked recessive form. The remaining 5% have either the autosomal recessive or autosomal dominant form of HED. The mode of inheritance may be determined in some instances by family history and in others by molecular genetic testing.HED is usually inherited as an X-linked recessive genetic trait and is caused by a mutation in the ectodysplasin-A (EDA) gene; in such cases, the disorder is fully expressed in males only. However, females who carry a single copy of the disease gene (heterozygote carriers) may exhibit some of the symptoms and findings associated with the disorder.
Fathers with XLHED will pass the gene to all of their daughters, who will be carriers for XLHED.A mother who is a carrier of XLHED has a one in four chance of having an affected son and a one in four chance of having a carrier daughter. Women who are carriers for XLHED may have no symptoms of XLHED, or they may have mild or even severe versions of them. Afflicted Chromosome, Gene and Loci
PhenotypeHair:Hair can be sparse on the scalp and body. It is usually light in colour, brittle, and slow to grow. It may be very fragile, curly, twisted and hard to manage. Body hair at puberty and beard growth in males may not be affected. Eyebrows and eyelashes can be sparse or missing.
Nails:Fingernails and toenails may be thickened, abnormally shaped, discoloured, ridged, slow to grow and/or brittle. Cuticles may be prone to infection.
Skin and Sweat Glands: For many ED syndromes, skin is lightly pigmented, is prone to rashes, eczema, and/or infections, and skin over the palms and soles may be thickened. Thus it is important to treat the skin to avoid infection, cracking and bleeding
Teeth:Because the development of tooth buds is impacted, teeth can be missing (hypodontia), or malformed (peg-shaped or pointed) and are slow to grow. Teeth can also be crowned. Lack of salvia can make teeth more prone to decay and poorly formed enamel means tooth care is very important.
Other Symptoms:Some EDS symptoms can include cleft-lip or palate, deformation of the hands or feet (including clefting or missing digits), hearing or vision deficiencies, nutritional needs, respiratory problems, dry nose, reduced tear duct functionality, light sensitive and/or dry reddened eyes.Physical Appearance:People with an ectodermal dysplasia syndrome may have distinctive cranial-facial features including cupped ears, saddle nose (flattened bridge), predominant forehead, small nostrils, lack of frenulum (under the tongue), or a broader nose.
Statistical Ratiois one of about 150 types ofectodermal dysplasiain humans. Before birth, these disorders result in the abnormal development of structures including theskin,hair, nails,teeth, andsweat glands.Hypohidrotic ectodermal dysplasia is an extremely rare genetic condition, affecting around 7,000 people.
Life SpanThe life span for a person diagnosed with the common Ectodermal Dysplasias is usually normal, and we have many middle-aged to elderly adult members.
TreatmentThere are no cure for the condition but symptoms can be managed.
ManagementManagement is multidisciplinary and requires evaluation by orthopedic, plastic and dental surgeons, ophthalmologists, dermatologists, and speech therapists. Surgery allows correction of orofacial and dental abnormalities and improves the function and appearance of the limbs. Ophthalmologic care (e.g. artificial tears in case of dry eyes) is necessary to avoid complications such as cataract and corneal scarring. Hot temperatures, heavy clothing, and exercise must be avoided in case of hypohidrosis.ClientModel with rare genetic disorder which has left her bald and without any teeth reveals how embracing her unique appearance helped to boost her fashion careerMelanie Gaydos, 27, has ectodermal dysplasia, a genetic disorder that affects the growth of teeth, nails, pores, cartilage and bonesDespite her condition, Melanie has forged a successful career as a model, and even counts Miley Cyrus as a fanMelanie says her medical condition 'doesn't bother' her and 'it never did'Melanie Gaydos