Spondyloepiphyseal dysplasia congenita
This paper tackles the nature of the rare genetic disease known as Spondyloepiphyseal dysplasia congenita, or SDE. Its genetic and molecular basis is also discussed together with the mechanism that explains how a mutation in the COL2A1 gene leads to SDE. The symptoms are also described as well as the current diagnostic and treatment methods. The paper ends with a list of various activities that a patient should avoid in order to facilitate recovery.
Introduction
Spondyloepiphyseal dysplasia congenita is a rare disorder characterized by abnormal bone tissue growth (dysplasia) which affects the bones of the spine (spondylo-) as well as the ends of long bones (epiphyseal), and that it is inherited and present at birth (congenita). It is sometimes referred to as SED congenital, SEDC, Spondyloepiphyseal dysplasia, congenital type or Spindyloepiphyseal Dysplasia, Congenital (What is Spondyloepiphyseal, 2010).
Children and adults with SED usually have a number of skeletal abnormalities, exhibit dwarfism, or having a short stature, and occasionally have trouble seeing and hearing. The incidence of SED is unknown though so far, there have been 175 cases reported in scientific and medical literature (Spondyloepiphyseal, 2010).
Genetic and Molecular Basis
Spondyloepiphyseal dysplasia congenital is an inherited disorder which results from mutations in the COL2A1 gene, or collagen type II, alpha1 gene, which is responsible for the synthesis of the pro-alpha1 (II) chain of Type II collagen. The role of Type II collagen in the reinforcement of the structure and strength of the bodys connective tissues during the early stages of development cannot be emphasized too heavily. Connective tissues support the bones and joints, muscles, organs, and skin. Most of type II collagen is present in cartilage, which has a key role in early bone development (COL2A1, 2010). Therefore, if the COL2A1 gene mutates, proper development of the bones and other connective tissues is impossible (Spondyloepiphyseal, 2010).
Type II collagen also forms part of the vitreous humor of the eye, the clear gel of the inner ear and that of the central portion of the intervertebral (IV) discs, or the nucleus pulposus. Thus problems with this collagen type may result in partial loss of vision and hearing as well as abnormal curvatures of the spine (COL2A1, 2010).
The more than 20 mutations found in the COL2A1, which indirectly cause SED, may result from the replacement of the amino acid glycine with a different amino acid at various places in the pro-alpha1 (II) chain. The resulting collagen chain is an abnormally shorter version of the original one, not to mention it causes SED (COL2A1, 2010).
Symptoms of the Disorder
Generally, children and adults with Spondyloepiphyseal dysplasia congenital are generally short in stature from birth, with short limbs and an unusually short trunk and neck, making three to four feet the maximum height among adults with SED (Spondyloepiphyseal, 2010).
Other symptoms involving the bones include the presence of kyphoscoliosis, lordosis, platyspondyly, coxa vara, a barrel-shaped chest, clubfoot, arthritis and reduced joint mobility even in childhood, flattened cheekbones, malar hypoplasia, cleft palate upon birth, narrow IV disc spaces, and a significant delay in the mineralization of the epiphyses, (Symptoms, 2010).
Symptoms involving the other tissues include muscle weakness, high myopia, other eye problems and hearing problems (Symptoms, 2010)
Current Diagnostic Methods
Diagnostic methods for Spondyloepiphyseal dysplasia congenita generally involve a variety of methods and techniques including laboratory and histologic studies, imaging studies, and prenatal testing. All of these methods require differential diagnoses with similar diseases such as Morquio disease, achondroplasia, diastrophic dysplasia, Kniest disease, Perthes disease and Metatrophic dwarfism (Wheeless, 2008).
For laboratory and histologic studies, the main indications of SDE include the presence of metachromatic inclusions in peripheral lymphocytes, microcystic areas of the proliferative zone, and vacuolated chondrocytes of the resting zone that contain PAS-positive cytoplasmic inclusions (Spondyloepiphyseal dysplasia Differential, 2008).
Radiographic imaging studies in patients with SED congenital will confirm the presence of a marked delay in the ossification of the epiphyses, varying degrees of platyspondyly, a steep anterior base of the skull, short and small iliac crests, short and broad tubular bones and many others. Other imaging techniques used are MRI, hip arthrography and CT scan (Spondyloepiphyseal dysplasia Differential, 2008).
Prenatal testing is also available (Spondyloepiphyseal dysplasia Differential, 2008).
Treatment Methods
Treatment methods for Spondyloepiphyseal dysplasia congenital involve a facilitated combination of medical care, surgical care, safety precautions and prevention. However, one very important aspect of SED treatment is the full cooperation of the family.
Proper medical care for people diagnosed with SED consists of regular visits to the ophthalmologist, neurologist, and pulmonologist. A pediatrician for the kids and a geneticist for those who can afford will also prove to be very helpful (Spondyloepiphyseal dysplasia Treatment, 2008).
Surgical care involves various techniques such as using braces, video-assisted thoracoscopic surgery, osteotomy, and many others (Spondyloepiphyseal dysplasia Treatment, 2008).
However, what makes a successful follow-up to a treatment is the determination the patient should have in avoiding activities that could possibly aggravate SED such as competitive sports, bicycling, aerobics, dancing, rowing, swimming, spinning, and water jogging (Spondyloepiphyseal dysplasia Treatment, 2008).
Spondyloepiphyseal dysplasia congenita is a destructive mix of its being genetic in origin and its being congenital. This fact makes the disease an extremely challenging even for the best methods of treatment. Diseases with origins in the cell, tissue or organs, and those that are acquired are relatively easier to treat unlike those with molecular and genetic bases especially those which are congenital. Nevertheless the advancement of medical science assures us that the conditions of patients suffering from SDE can be alleviated with early and correct diagnosis, regular consultations with the doctor, intelligent choices of treatment as well as the full cooperation of the family of the patient and the patient himself.
Introduction
Spondyloepiphyseal dysplasia congenita is a rare disorder characterized by abnormal bone tissue growth (dysplasia) which affects the bones of the spine (spondylo-) as well as the ends of long bones (epiphyseal), and that it is inherited and present at birth (congenita). It is sometimes referred to as SED congenital, SEDC, Spondyloepiphyseal dysplasia, congenital type or Spindyloepiphyseal Dysplasia, Congenital (What is Spondyloepiphyseal, 2010).
Children and adults with SED usually have a number of skeletal abnormalities, exhibit dwarfism, or having a short stature, and occasionally have trouble seeing and hearing. The incidence of SED is unknown though so far, there have been 175 cases reported in scientific and medical literature (Spondyloepiphyseal, 2010).
Genetic and Molecular Basis
Spondyloepiphyseal dysplasia congenital is an inherited disorder which results from mutations in the COL2A1 gene, or collagen type II, alpha1 gene, which is responsible for the synthesis of the pro-alpha1 (II) chain of Type II collagen. The role of Type II collagen in the reinforcement of the structure and strength of the bodys connective tissues during the early stages of development cannot be emphasized too heavily. Connective tissues support the bones and joints, muscles, organs, and skin. Most of type II collagen is present in cartilage, which has a key role in early bone development (COL2A1, 2010). Therefore, if the COL2A1 gene mutates, proper development of the bones and other connective tissues is impossible (Spondyloepiphyseal, 2010).
Type II collagen also forms part of the vitreous humor of the eye, the clear gel of the inner ear and that of the central portion of the intervertebral (IV) discs, or the nucleus pulposus. Thus problems with this collagen type may result in partial loss of vision and hearing as well as abnormal curvatures of the spine (COL2A1, 2010).
The more than 20 mutations found in the COL2A1, which indirectly cause SED, may result from the replacement of the amino acid glycine with a different amino acid at various places in the pro-alpha1 (II) chain. The resulting collagen chain is an abnormally shorter version of the original one, not to mention it causes SED (COL2A1, 2010).
Symptoms of the Disorder
Generally, children and adults with Spondyloepiphyseal dysplasia congenital are generally short in stature from birth, with short limbs and an unusually short trunk and neck, making three to four feet the maximum height among adults with SED (Spondyloepiphyseal, 2010).
Other symptoms involving the bones include the presence of kyphoscoliosis, lordosis, platyspondyly, coxa vara, a barrel-shaped chest, clubfoot, arthritis and reduced joint mobility even in childhood, flattened cheekbones, malar hypoplasia, cleft palate upon birth, narrow IV disc spaces, and a significant delay in the mineralization of the epiphyses, (Symptoms, 2010).
Symptoms involving the other tissues include muscle weakness, high myopia, other eye problems and hearing problems (Symptoms, 2010)
Current Diagnostic Methods
Diagnostic methods for Spondyloepiphyseal dysplasia congenita generally involve a variety of methods and techniques including laboratory and histologic studies, imaging studies, and prenatal testing. All of these methods require differential diagnoses with similar diseases such as Morquio disease, achondroplasia, diastrophic dysplasia, Kniest disease, Perthes disease and Metatrophic dwarfism (Wheeless, 2008).
For laboratory and histologic studies, the main indications of SDE include the presence of metachromatic inclusions in peripheral lymphocytes, microcystic areas of the proliferative zone, and vacuolated chondrocytes of the resting zone that contain PAS-positive cytoplasmic inclusions (Spondyloepiphyseal dysplasia Differential, 2008).
Radiographic imaging studies in patients with SED congenital will confirm the presence of a marked delay in the ossification of the epiphyses, varying degrees of platyspondyly, a steep anterior base of the skull, short and small iliac crests, short and broad tubular bones and many others. Other imaging techniques used are MRI, hip arthrography and CT scan (Spondyloepiphyseal dysplasia Differential, 2008).
Prenatal testing is also available (Spondyloepiphyseal dysplasia Differential, 2008).
Treatment Methods
Treatment methods for Spondyloepiphyseal dysplasia congenital involve a facilitated combination of medical care, surgical care, safety precautions and prevention. However, one very important aspect of SED treatment is the full cooperation of the family.
Proper medical care for people diagnosed with SED consists of regular visits to the ophthalmologist, neurologist, and pulmonologist. A pediatrician for the kids and a geneticist for those who can afford will also prove to be very helpful (Spondyloepiphyseal dysplasia Treatment, 2008).
Surgical care involves various techniques such as using braces, video-assisted thoracoscopic surgery, osteotomy, and many others (Spondyloepiphyseal dysplasia Treatment, 2008).
However, what makes a successful follow-up to a treatment is the determination the patient should have in avoiding activities that could possibly aggravate SED such as competitive sports, bicycling, aerobics, dancing, rowing, swimming, spinning, and water jogging (Spondyloepiphyseal dysplasia Treatment, 2008).
Spondyloepiphyseal dysplasia congenita is a destructive mix of its being genetic in origin and its being congenital. This fact makes the disease an extremely challenging even for the best methods of treatment. Diseases with origins in the cell, tissue or organs, and those that are acquired are relatively easier to treat unlike those with molecular and genetic bases especially those which are congenital. Nevertheless the advancement of medical science assures us that the conditions of patients suffering from SDE can be alleviated with early and correct diagnosis, regular consultations with the doctor, intelligent choices of treatment as well as the full cooperation of the family of the patient and the patient himself.
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