HIDROTIC ECTODERMAL DYSPLASIA
 
PEDBASE.org - The Pediatric Database - Detailed information of HIDROTIC ECTODERMAL DYSPLASIA

 

HIDROTIC ECTODERMAL DYSPLASIA

 

DEFINITION:

An autosomal dominant disorder characterized by hypotrichosis, abnormal nails, and hyperkeratosis of the palms and soles.

EPIDEMIOLOGY:

  • incidence: rare
  • age of onset:
    • infancy -> childhood
  • risk factors:
    • familial - autosomal dominant with complete penetrance
      • chrom.#: ?
      • gene: ?
    • M = F
    • French and Chinese populations

PATHOGENESIS:

1. Background

  • also called Clouston Ectodermal Dysplasia, Fischer-Jacobsen- Clouston Syndrome, Jacobsen Syndrome, Ungual Ectodermal Dysplasia
  • one in a heterogeneous group of disorders (there may be over 120 different types) characterized by a number of defects involving the teeth, skin, and appendageal structures (hair, nails, and eccrine and sebaceous glands):

    1. Hypohidrotic (Anhidrotic) Ectodermal Dysplasia

    2. Hidrotic Ectodermal Dysplasia (Clouston Type)

    3. EEC Syndrome

    4. Rapp-Hodgkin Ectodermal Dysplasia

    5. Robinson-Type Ectodermal Dysplasia
  • the Ectodermal Dysplasias may be due to disturbances in the tissue derived from ectoderm -> absent or hypoplastic glandular systems:
    1. Eccrine Glands - sweating deficit
    2. Lacrimal Glands - lacrimation deficit
    3. Mucous Glands - respiratory manifestations, atopic disease
    4. Sebaceous Glands - skin manifestations

CLINICAL FEATURES:

1. Eccrine Manifestations

  • normal sweating

2. Integument Manifestations

1. Hypotrichosis

  • sparse, thin, fragile hair with reduced tensile strength
  • absence of eyebrows and lashes

2. Nails

  • dystrophic, hypoplastic, or absent
  • at risk for subungual infections

3. Skin

  • hyperkeratosis (thick, rough skin with brownish pigmentation) of palms and soles
  • hyperpigmentation over knees, elbows, and knuckles

3. Dental Manifestations

  • usually normal but can have small teeth with many caries

INVESTIGATIONS:

1. Skeletal X-Rays

  • thickening of the skull bones
  • tufting of the terminal phalanges

MANAGEMENT:

1. Supportive

  • multidisciplinary approach:
    • Paediatrics, Dermatology, Dentistry
    • genetic counselling

2. Prognosis

  • normal life span

REFERENCES:

1. Buyse, Mary-Louise, Birth Defects Encyclopedia (2nd Edition). p. 600-601, (1994).
2. Nelson Textbook of Pediatrics (15th Edition). p. 1837, (1996).

INTERNET LINKS:

HED Foundation

 

 

 

Pediatric Database - HIDROTIC ECTODERMAL DYSPLASIA

 

Pediatric Organization - Pedbase [at] Gmail.com

 
1994 -2007 Pedbase.org 

Powered by Database of Pediatrics- HIDROTIC ECTODERMAL DYSPLASIA