What Are the Symptoms of Galactosemia?

Galactosemia is a toxic clinical metabolic syndrome with an increase in blood galactose. Congenital defects in any of the three related enzymes in galactose metabolism can cause galactosemia.

Basic Information

English name: galactosemia
Visiting department: Internal medicine
Common locations: Liver, kidney, crystal and brain tissue

Common causes: 1-phosphate-galactosyluridine transferase deficiency
Common symptoms: Breastfeeding, vomiting, nausea, diarrhea, weight gain, liver enlargement, jaundice, bloating, hypoglycemia, proteinuria, etc.

Causes of galactosemia

Classical galactosemia occurs in the second step of galactose metabolism, which is an autosomal recessive inheritance caused by the accumulation of 1-phosphate-galactose, a deficiency of 1-phosphate-galactose uridine transferase. disease. Liver, kidney, crystal and brain tissue are the main affected organs.

Clinical manifestations of galactosemia

There are many regional variants of galactose-1-phosphate urylyltransferase, and the activity of the enzyme is different. The enzyme protein molecules show different swimming speeds during electrophoresis, which helps to identify the types. There are fewer variants of galactokinase, and the clinical manifestations of galactosemia are significantly different depending on the type and duration of the disease. Those who are mild may have no clinical symptoms, and the most severe cases are violent.

Acute course

Most children have galactose in breastfeeding or artificially fed cow's milk in the first few days after birth, and have breast rejection, vomiting, nausea, diarrhea, weight loss, liver enlargement, jaundice, bloating, hypoglycemia, proteinuria, etc. Performers should consider the possibility of galactosemia, and perform relevant laboratory inspections immediately. If they can be detected in time and take corresponding measures, cataracts and mental development disorders may occur quickly.

2. Mild course

Most of them have no acute symptoms, but gradually develop dysphonia, cataracts, mental retardation and cirrhosis with age.

3. Other

Such as a false brain tumor, a rare manifestation, this line of galactose accumulates in the brain, followed by conversion to galactitol, which causes cerebral edema and increased intracranial pressure.

Galactosemia test

Laboratory inspection

(1) Urine galactose test Urine glucose positive, glucose oxidase method urine glucose negative, paper chromatography can identify it as galactose.

(2) Screening for galactosemia in newborns . Screen the defective enzymes using the Beutler method and observe the presence or absence of fluorescence. Use this as a basis for final assessment. There is no fluorescence in this disease. Defects in enzyme activity can also be reflected in liver, intestinal mucosa, fibroblasts and leukocytes.

(3) Determination of blood galactose concentration The normal concentration is 110-194 mol / L (galactose oxidase or galactose dehydrogenase method), and the patient's blood concentration increases.

(4) Determination of urinary galactose and galactitol concentrations can be determined by enzyme method.

(5) Determination of galactose 1-phosphate of red blood cells.

(6) Determination of enzymes related to galactose metabolism This is an important basis for the diagnosis of this disease.

(7) Determination of non-specific biochemical indicators, such as proteinuria and glucosuria.

2. Auxiliary inspection

(1) B-ultrasound was selected based on clinical manifestations.

(2) Enzyme activity measurement with fetal blood taken through a fetal scope Measure the content of galactitol and the enzyme activity in amniotic fluid cells. The mutation analysis of enzyme gene can be used for prenatal diagnosis of fetus.

(3) Galactose respiration test The quantitative conversion of 13C-galactose into 13CO2 can be measured to understand the body's ability to oxidize galactose.

Diagnosis of galactosemia

The diagnosis is mainly based on clinical symptoms and related enzyme activity measurements. Those with normal urine glucose levels and a positive Bann test may be suspected of galactosemia. A diagnosis of galactose metabolism enzyme deficiency combined with red blood cells is usually made. If you suspect that the fetus may have galactosemia before birth, you can perform prenatal diagnosis by amniocentesis, or take umbilical cord blood at birth to check the enzyme activity in red blood cells.

Elevated blood galactose levels in pregnant women, regardless of the presence or absence of galactose-1-phosphate uridine transferase, can cause damage to the fetus, including permanent intellectual disability.

Differential diagnosis of galactosemia

Pay attention to the identification with infantile hepatitis syndrome, infantile hepatitis syndrome has obvious liver damage, and jaundice is mainly caused by direct bilirubin elevation.

Galactosemia complications

There may be neurological deafness in childhood. A few patients can develop retinal and vitreous hemorrhage, jaundice and liver enlargement, cirrhosis, peritoneal effusion, liver failure, bleeding, complicated by Escherichia coli septicemia, delayed growth, retarded intellectual development, hyperchloric acidosis, protein Urine, amino acid urine and hypoglycemia.

Galactosemia Treatment

1. Intravenous glucose, fresh plasma, pay attention to electrolyte supplement.

2. Antibiotics

Appropriate antibiotics should be used in children with sepsis, and active supportive treatment should be given.

Prognosis of galactosemia

The prognosis of a child depends on the availability of early diagnosis and treatment. The majority of those who have not been treated properly die during the neonatal period, with an average life expectancy of about 6 weeks. Even if they survived, they will still have mental retardation in the future. Most children with early diagnosis have normal growth and development, but most of them may have problems with learning difficulties, language difficulties, or behavioral abnormalities in adulthood. Almost all female children develop hypogonadism in their older age. The cause is not clear.