(Revised at the Villefranche Meeting 1997)
TYPE |
CLINICAL FEATURES |
INHERITANCE |
BASIC DEFECT |
|
CLASSICAL
(formerly EDS I & II gravis and mitis type)
|
Major: Skin hyperextensibility; widened thin scars; joint hypermobility
Minor: Smooth velvety skin; molluscoid pseudotumours; complications of loose joints; muscle hypotonia; easy bruising;
manifestations of tissue extensibility (hernia, cervical insufficiency, etc.); positive family history.
|
Autosomal dominant
|
Abnormality of the pro alpha 1 (V) or pro alpha 2 (V) chain of the type V collagen encoded by COL5A1 and COL5A2 genes (in some but not all families).
|
HYPERMOBILITY
(formerly EDS III hypermobile type )
|
Major: Generalised joint hypermobility; skin hyperextensibility and smooth or velvety.
Minor: Recurrent joint dislocations; chronic limb and joint pains; positive family history.
|
Autosomal dominant
|
Unknown
|
VASCULAR
(formerly EDS IV arterial or ecchymotic type)
|
Major: Arterial/intestinal/uterine fragility or rupture; easy bruising; characteristic facial appearance.
Minor: Hypermobility of small joints; tendon and muscle rupture; club feet; varicose veins; positive family history; sudden death in close relative.
|
Autosomal dominant
|
Structural defects in the proa 1 (III) chain of collagen type III, encoded by the COL3A1 gene.
|
KYPHOSCOLIOSIS
(formerly EDS VI ocular or scoliosis type)
|
Major: Generalised joint laxity; severe muscle hypotonia in infancy; scoliosis present at birth and progressive; fragility of the sclera of the eye.
Minor: Tissue fragility; easy bruising; arterial rupture; Marfanoid body shape; microcomea; skeletal osteopenia on X-ray; positive family history of affected siblings.
|
Autosomal recessive
|
Deficiency of lysyl hydroxylase, a collagen modifying enzyme.
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ARTHROCHALASIA
(formerly included in EDS VII)
|
Major: Severe generalised joint hypermobility with dislocations; congenital bilateral hip dislocation.
Minor: Skin hyperextensibility; tissue fragility and scarring: easy bruising; muscle hypotonia; Kyphoscoliosis; skeletal osteopenia on X-ray; positive family history.
|
Autosomal dominant
|
Deficiencies of the proa(I) or proa 2(I) chains of collagen type due to skipping of exon 6 in the COL1A1 or COL1A2 gene.
|
|
DERMATOSPRAXIS
(formerly included in EDS VII)
|
Major: Severe skin fragility; sagging, redundant skin.
Minor: Soft, doughy skin texture, easy bruising; premature rupture of foetal membranes; hernias.
|
Autosomal dominant
|
Deficiency of procollagen 1 N-terminal peptidase in collagen type 1.
|
Other Rare Forms of EDS
EDS V: X-linked type, resembles the Classical type, in mild to moderate severity. Delineated in a single large family in the UK .
EDS VIII: Periodontal type resembles the Classical type with the addition of fragility of the gums. Very rare. Syndromic status uncertain. Autosomal dominant.
EDS X: Resembles the Classical type, in mild degree, with the additional feature of abnormal platelet aggregation. Syndromic status uncertain. Autosomal recessive?
Entries now Removed From the EDS Classification
EDS IX Now termed 'occipital horn syndrome'. X-linked disorder of copper metabolism which is allelic to the Menkes syndrome.
EDS XI: Now termed 'familial joint hypermobility'. Resembles hypermobility form of EDS.
 N.B. A major clinical feature has high diagnostic specificity, because it is infrequent in other conditions and in the general population. The presence of one or more major clinical feature is either necessary for clinical diagnosis or highly indicative and warrants laboratory confirmation whenever possible. A minor clinical feature is a sign of lesser diagnostic specificity. The presence of one or more minor clinical feature contributes to the diagnosis of a specific type of EDS. However, in the absence of major clinical features they are not sufficient to establish the diagnosis. The presence of minor clinical feature might be suggestive of the diagnosis of (an) EDS-like condition(s), the nature of which will be elucidated when the molecular basis becomes known.
The views expressed are those of the author(s) and should not be construed to represent the opinions or policy of the Ehlers-Danlos Support Group or it's Trustees.
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Medical Information