Cysteinuria Screening

Screening for cysteineuria is an important test in newborn screening. Children with cysteuria are normal at birth, more than 5 to 9 months after birth. 1 urine homocysteine ​​determination, can be used screening method, that is, sodium nitroprusside test: 1ml of urine is added to 5% sodium cyanide aqueous solution, placed for 5 minutes, add a drop of 5% sodium nitroprusside solution, red or purple red is positive , indicating that there is an excess of sulfur-containing amino acids in the urine. 2 The diagnosis depends on the enzyme activity. The activity of the enzyme can be measured by skin fibroblasts. Heterozygotes can also be detected by this method. 3 prenatal diagnosis can measure the enzyme activity of amniocytes. Basic Information Specialist classification: urinary examination classification: urine / kidney function test Applicable gender: whether men and women apply fasting: fasting Tips: Try to eat less spicy and stimulating food. Normal value There is no excessive sulfur-containing amino acid, cystathionine synthetase, methyltetramethane-homocysteine ​​methyltransferase, and normal content of 5,10-N-methylenetetrahydrofolate reductase in urine. Clinical significance Abnormal results: The child has delayed development and short stature. He can sit independently until he is 1 year old. He can barely walk until he is 2 years old. After the childhood, the reaction was slow and the language was disordered. The degree of mental retardation varies from person to person, and mental retardation and slow response have a tendency to develop slowly. In addition to seizures, other neurological symptoms such as myoclonic seizures, delirium, and deep reflexes may occur. Newborns need to be examined for abnormal development in the population. Precautions Taboo before the examination: poor rest, improper diet, excessive fatigue. Requirements for inspection: Actively cooperate with the doctor's work. Inspection process 1 urine homocysteine ​​determination, can be used screening method, that is, sodium nitroprusside test: 1ml of urine is added to 5% sodium cyanide aqueous solution, placed for 5 minutes, add a drop of 5% sodium nitroprusside solution, red or purple red is positive , indicating that there is an excess of sulfur-containing amino acids in the urine. 2 The diagnosis depends on the enzyme activity. The activity of the enzyme can be measured by skin fibroblasts. Heterozygotes can also be detected by this method. 3 prenatal diagnosis can measure the enzyme activity of amniocytes. Heterozygotes can also be detected by this method by measuring the activity of the enzyme. Not suitable for the crowd Inappropriate crowd: None. Adverse reactions and risks No obvious complications and harms.

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