(Genetic skeletal dysplasias)

The Osteochondrodysplasias growth abnormalities of bone and cartilage lead to incorrect skeletal development, often manifested in a short-link dwarfism. The diagnosis is made by clinical examination, X-rays and in some cases by a genetic test. The treatment is surgical.

The basic genetic defects have been identified for most Osteochondrodysplasias. The mutations typically cause disturbances in the function of proteins involved in the growth and development of connective tissue, bone and cartilage (types of osteochondrodysplastischen short stature).

The Osteochondrodysplasias growth abnormalities of bone and cartilage lead to incorrect skeletal development, often manifested in a short-link dwarfism. The diagnosis is made by clinical examination, X-rays and in some cases by a genetic test. The treatment is surgical. The basic genetic defects have been identified for most Osteochondrodysplasias. The mutations typically cause disturbances in the function of proteins involved in the growth and development of connective tissue, bone and cartilage (types of osteochondrodysplastischen short stature). Short stature is a disease with very short stature (height of adults <145 cm), often associated with a disproportionate size of the trunk and extremities. Achondroplasia is the most common and well known form, but many other different forms of short stature have been described with short limbs, which differ substantially in their genetic cause, its course and its prognosis (types of osteochondrodysplastischen short stature). The lethal running the form of short stature (thanatophoric dysplasia) causes severe chest wall malformations and respiratory failure in newborns and thus leads to death. Types of osteochondrodysplastischen short stature disorder symptoms and discomfort Common Inheritance defect gene achondroplasia Dished forehead, saddle nose, lumbar lordosis, bowlegged AD fibroblast growth factor receptor 3 chondrodysplasia punctata variable extraskeletal manifestations X-rays show epiphyseal stippling in infancy due to calcification s. down s. below chondrodysplasia punctata (rhizomelic form) selected shortening of the proximal extremities death in infancy AR peroxisome type-2 receptor (PTS2) chondrodysplasia punctata (Conradi-Hünermann form) Mild, asymmetric reduction of the limbs Benign AD or XL dominant Delta (8) - Delta (7) -Sterolisomerase emopamil binding protein (EBP) Chondroektodermale dysplasia (Ellis-van Creveld [EVC] syndrome) shortening of the distal extremities, postaxial polydA ktylie, structural heart defects AR EVC, EVC2 Diastrophic dysplasia Pronounced short stature with rigid thumb and clubfoot AR Solute carrier family 26 (sulfate transporter), member 2 (SLC26A2) hypochondroplasia As symptoms of achondroplasia but milder AD fibroblast growth factor receptor 3 (FGFR3 -Not all patients) Mesomelische dysplasia * Mainly shortening of the forearms un d leg Normal face and spine AD or AR Not defined metaphyseal chondrodysplasia † In some forms: malabsorption, neutropenia, Thymolymphopenie AR or AD parathyroid hormone receptor (PTHR), type X collagen (Col10a1) Multiple epiphyseal dysplasia light pronounced dwarf growth, normal spine and face sometimes Kurzfingrigkeit, hip dysplasia (often referred to as the first symptom) Very heterogeneous AR or AD Solute carrier family 26 (sulfate transporter), member 2 (SLC26A2; AR form) pseudoachondroplasia Normal face, different degrees of dwarfism and kyphoscoliosis heterogeneous AD or AR cartilage oligomeric matrix protein (COMP) Spondyloepiphyseale dysplasia Mostly kyphoscoliosis Sometimes myopia and a flat face heterogeneous AD, AR, or XL type II collagen (COL2A1) tracking protein particle complex subunit 2 (TRAPPC2, also known as SEDL) * There are several forms of the same name (z. B. Nievergelt, Langer). † There are many different forms of the same name (z. B. Jansen, Schmid, McKusick). AD = autosomal dominant; AR = autosomal recessive; XL = X-linked. Diagnostic X-rays The characteristic radiological changes are diagnosable-setting. The whole body of each affected newborns, even that of stillbirths should be examined radiologically, because the diagnostic accuracy for further guidance is essential. Prenatal diagnosis is in some cases by fetoscopy or ultrasonic possible (eg. For example, when the shortening of the link is marked). Standard laboratory tests are unnecessary, but a molecular diagnosis is possible for chondrodysplasia with known molecular defects. Genetic tests are recommended when no diagnosis can be made based on clinical findings or if genetic counseling is desired. Treatment Sometimes surgical limb lengthening or joint replacement In achondroplasia treatment with human growth hormones is usually not effective. An increase in body size can be achieved by a surgical leg lengthening. In this and other deadly Osteochondrodysplasias operations (eg. As the hip) can help to improve joint function. Hypoplasia of the dens may make them particularly vulnerable to subluxation of the first and second cervical vertebrae and spinal cord compression. Therefore, the Dens should be assessed preoperatively. Is it pathological, the head of the patient should be carefully supported if it is overstretched for intubation. Since the inheritance in most forms is known, necessarily should be genetic counseling. Organizations such as the "Little People of America" ??(www.lpaonline.org) provide stakeholders information material and act as advocates of those affected. Similar companies are active in other countries (editor's note:... In Germany, for example, are www.orpha.net, www.exostosen.de, www.marfan.de). Important points Osteochondrodysplasias are hereditary abnormalities of the size growth and development of connective tissue, bone and / or cartilage. There are many types that vary in their genetic background, their course and their prognosis, but all lead to significant short stature and often disproportionate growth of the trunk and extremities. The diagnosis is based on clinical manifestations and on the identification of characteristic X-ray changes. Growth Hormone treatments are usually ineffective.

Health Life Media Team

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