Classification of mucopolysaccharidosis?
summary
Proteoglycan catabolism disorder caused by congenital defect of proteoglycan degrading enzyme. It is characterized by excessive accumulation and excretion of oligosaccharides. Mucopolysaccharidosis type I (H) is also known as Chengliu disease because it has an ugly face and looks like a monster in the gutter under the eaves of ancient Chinese buildings. The number of male patients was more than that of female patients, most of them were the offspring of close relatives, and most of them had family history. Classification of mucopolysaccharidosis?
Classification of mucopolysaccharidosis?
The clinical diagnosis of mucopolysaccharidosis is based on the clinical manifestations, the characteristics of X-ray and the increase of mucopolysaccharidosis excreted in urine. Toluidine blue staining method can be used as a screening test for this disease, and cellulose acetate film electrophoresis can also be used to distinguish the types of mucopolysaccharide excreted from the blood and assist in typing. The specific enzyme activity of leukocytes or skin fibroblasts should be determined for the diagnosis of MPs. Most of the mucopolysaccharidosis can be diagnosed by amniotic fluid cDNA gene analysis.
Mucopolysaccharidosis type I-h (mps-ih), also known as Hurler syndrome, hurler gene is located on chromosome 1. In mucopolysaccharide, dermatan sulfate and heparin sulfate contain l-iduronic acid, which needs to be degraded α- L-iduronidase. Due to the lack of this enzyme, the degradation of its precursor was blocked and accumulated in the body. Dermatan sulfate and heparin sulfate are the structural components of cornea, cartilage, bone, skin, fascia, heart valve and vascular connective tissue, and most of them are the structural components of the outer layer of cell membrane. Accumulation of mucopolysaccharide can be released after cell death.
Mucopolysaccharidosis is caused by congenital defect of cytolysosomal acid hydrolase. The main manifestations were severe skeletal deformity, hepatosplenomegaly, mental retardation and other deformities. The most reliable method for prenatal diagnosis of mucopolysaccharidosis is to determine the specific enzyme activity in cultured amniotic fluid cells. Two simple and practical methods are toluidine blue qualitative method and uronic acid semi quantitative method.
matters needing attention
Most of the cases are autosomal recessive inheritance. Mucopolysaccharide can be found in the fibroblast culture of the patients and their heterozygous relatives. For those with positive family history, amniotic fluid examination can be done at 16-20 weeks of gestation to determine the content of mucopolysaccharide in amniotic fluid. Amniotic fluid cell culture can also be used to determine enzyme activity. If prenatal diagnosis, timely termination of pregnancy, to prevent mucopolysaccharidosis baby born.
