IllnessEktodermale Dysplasie, hydrotische, Clouston; Differentialdiagnose

NGS +

Ectodermal Dysplasias (ED) include about 150 disorders characterized by abnormal development of some or all ectodermal structures (skin, hair, nails, teeth, sweat glands). Hydrotic ED is characterized by abnormalities of the hair, nails and skin. In the Couston type (hidrotic ED 2), teeth and sweat glands are not affected. In infants with Clouston syndrome, the sparse hair on the head is brittle, patchy and lighter in color than the hair of other family members. During puberty, hair problems can develop into complete alopecia. Eye lashes, eyebrows, axillary and pubic hair are also affected. Nail dystrophy is characteristic, with nails growing slowly, becoming misshapen and thick. Clouston patients show palmoplantar hyperkeratosis, hyperpigmentation around the joints and clubbing. Clouston syndrome is caused by mutations in the GJB6 gene, which encodes a member of the connexin family of proteins that form gap junctions in the skin as well as in hair follicles and nail beds. Hydrotic EDs are often inherited in an autosomal dominant manner with high penetrance, but autosomal recessive and X-linked forms also occur. Because the symptoms of the different ED forms are often difficult to distinguish, panel analysis is preferred; the diagnostic yield is not yet known. Therefore, a negative molecular genetic result does not exclude the clinical diagnosis.

Reference: https://www.ncbi.nlm.nih.gov/books/NBK1200/

• Allelic: Acrokeratosis verruciformis (ATP2A2)
• Allelic: Bart-Pumphrey syndrome (GJB2)
• Allelic: Deafness, AD 3A (GJB2)
• Allelic: Deafness, AD 3B (GJB6)
• Allelic: Deafness, AR 1A (GJB2)
• Allelic: Deafness, AR 1B (GJB6)
• Allelic: Deafness, digenic GJB2/GJB6 (GJB2/GJB6)
• Allelic: Hair morphology 1, hair thickness (EDAR)
• Allelic: Immunodeficiency 33 (IKBKG)
• Allelic: Incontinentia pigmenti (IKBKG)
• Allelic: Steatocystoma multiplex (KRT17)
• Allelic: Woolly hair, AD (KRT74)
• Darier disease (ATP2A2)
• Ectodermal dysplasia + immunodeficiency 1 (IKBKG)
• Ectodermal dysplasia 1, hypohidrotic, XL (EDA)
• Ectodermal dysplasia 10A, hypohidrotic/hair/nail type, AD (EDAR)
• Ectodermal dysplasia 10B, hypohidrotic/hair/tooth type, AR (EDAR)
• Ectodermal dysplasia 11A, hypohidrotic/hair/tooth type, AD (EDARADD)
• Ectodermal dysplasia 11B, hypohidrotic/hair/tooth type, AR (EDARADD)
• Ectodermal dysplasia 2, Clouston type (GJB6)
• Ectodermal dysplasia 4, hair/nail type (KRT85)
• Ectodermal dysplasia 7, hair/nail type (KRT74)
• Ectodermal dysplasia 9, hair/nail type (HOXC13)
• Hypotrichosis 3 (KRT74)
• Hystrix-like ichthyosis with deafness (GJB2)
• Keratitis-ichthyosis-deafness syndrome (GJB2)
• Keratoderma, palmoplantar, with deafness (GJB2)
• Odontoonychodermal dysplasia (WNT10A)
• Pachyonychia congenita 1 (KRT16)
• Pachyonychia congenita 3 (KRT6A)
• Pachyonychia congenita 4 (KRT6B)
• Palmoplantar keratoderma, nonepidermolytic, focal (KRT16)
• Palmoplantar keratoderma, nonepidermolytic, focal or diffuse (KRT6C)
• Schopf-Schulz-Passarge syndrome (WNT10A)
• Tooth agenesis, selective, 4 (WNT10A)
• Tooth agenesis, selective, XL 1 (EDA)
• Vohwinkel syndrome (GJB2)