- Syndrome, Ehlers-Danlos
- A heritable disorder of connective tissue with easy bruising, joint hypermobility (loose joints), skin laxity, and weakness of tissues. There are a number of different types of Ehlers-Danlos syndrome (EDS) which share the foregoing features but can be categorized into at least nine different types: Classical Types(Types I & II) Marked joint hypermobility, skin hyperextensibility (laxity), and fragility. The smooth, velvety skin is fragile and tears or bruises easily with minor trauma. Joint dislocations and scoliosis are common. Joint instability can lead to sprains and strains. This classical type is inherited as an autosomal dominant trait. Cases of this disease are now known due to mutations in collagen genes — specifically, in the collagen alpha-1(V) gene (COL5A1), the collagen alpha-2(V) gene (COL5A2), and the collagen alpha-1(I) gene (COL1A1). Hypermobility Type (Type III) Joint hypermobility is the major manifestation. Any joint can be affected and dislocations are frequent. Inherited as an autosomal dominant trait. A defect in the gene for type III collagen (COL3A1) is sometimes the basis of this disease. Mutations in other genes may also cause it. Vascular Type (Type IV, the arterial form) Spontaneous rupture of arteries and bowel is a serious manifestation that can lead to death. Clubfoot can be present at birth. Skin laxity variable. Veins can be very visible through the skin. Inherited as an autosomal dominant trait. A defect in the gene for type III collagen (COL3A1) is usually the basis of this disease. Kyphoscoliosis Type (Type VI) Fragile globe of the eyes, significant skin and joint laxity, and severe curvature of the spine (kyphoscoliosis). Inherited as an autosomal recessive trait. Molecular defects have been identified in the gene for the enzyme lysyl hydroxylase (PLOD) in some patients with EDS VI. Arthrochalsia Type (type VIIB, arthrochalasis multiplex congenita) Patients are short in height and severely affected by joint laxity and dislocations. Skin involvement is variable. This disorder is inherited as an autosomal dominant trait. A skin biopsy is diagnostic. Mutation at one of at least 2 collagen genes, COL1A1 and COL1A2, can produce this disease. Dermatosparaxis Type (Type VIIC) Patients have severely fragile skin that is soft and doughy with sagging and folding. This form of EDS is an autosomal recessive trait and can be diagnosed with a skin biopsy. Mutations in a gene called ADAMTS2 have been identified in this disorder. Periodontosis Type(Type VIII) Patients with Type VIII EDS have different degrees of joint hypermobility, as well as inflammation of the gums and bone adjacent to the teeth (periodontitis). This disorder is inherited as an autosomal dominant trait. Other variant types of EDS have been reported, in some cases in single families. Suffice it to say that EDS is a genetically diverse and heterogeneous disorder.
Medical dictionary. 2011.