What are the symptoms of maple sugar diabetes? Maple syrup urine disease (MSUD), also known as diabetes and branched-chain ketonuria, is an autosomal recessive genetic disease. Because of the congenital defect of branched-chain ketoacid decarboxylase, the decomposition and metabolism of branched-chain amino acids are blocked, and it is named after a large amount of α-keto-β-methylvaleric acid is excreted in children's urine, which has the sweetness of maple syrup.
It mainly invades the nervous system, showing the symptoms of progressive brain injury, which is an important reason for children's mental retardation. In severe cases, convulsions, paralysis or severe metabolic disorders may occur. Clinically, the disease can be divided into five types.
1. Typical maple syrup urine sickness: the most common and serious one. He was in good condition at birth, and generally appeared drowsiness or irritability, difficulty in breastfeeding, weight loss and other symptoms on the 4 th to 7 th day after birth; Muscle tension alternately decreases and increases, such as cerebral palsy, convulsion, coma, shallow breathing and intermittent cyanosis. The child's urine smells of maple syrup; Some children may be accompanied by hypoglycemia, ketoacidosis and fullness of the anterior fontanel. Most children died of recurrent metabolic disorder or neurological dysfunction within a few months after birth, and a few survivors also suffered from mental retardation, spastic paralysis, cortical blindness and other neurological disabilities.
2. light (or intermediate) type: the enzyme activity is 3% ~ 30% of that of normal people, and the branched-chain amino acids and branched-chain ketoacids in blood only slightly increase; Excess branched ketoacids are excreted through urine. A few cases may have acute metabolic disorder, such as ketoacidosis. It is characterized by mental retardation, but there are no other typical symptoms and signs of the nervous system, and there is no characteristic of intermittent attacks.
3. Intermittent type: the enzyme activity is 5% ~ 20% of that of normal people. Usually in infancy or late childhood, but it can be as late as adulthood. Anorexia, vomiting, apathy, lethargy, ataxia, behavior change, gait instability, severe convulsions, coma, and even death, urine tastes like maple syrup. A few people are mentally retarded. The course of disease is different, and there may be many ups and downs. Some children die of acute ketosis.
Maple sugar diabetes can be divided into five subtypes according to the age of onset, severity of symptoms, responsiveness to treatment and biochemical characteristics: classic type, intermediate type, intermittent type, thiamine reaction type and dihydrothionyl amide dehydrogenase deficiency lactic acid poisoning type.
Among all types, the classic type is the most common, and the incidence of neonatal period is mostly this type. Symptoms appear in 4 ~ 7 days after birth and get worse gradually, showing drowsiness, weight loss and metabolic disorder. Progressive muscle tone increase and muscle tone decrease alternately suggest severe encephalopathy, and children are prone to convulsions and coma. Untreated people usually die in a short time.
Disease treatment
Although the disease cannot be cured, timely and correct treatment can make the child survive and improve the symptoms. Urgent measures should be taken to treat the acute crisis of metabolic decompensation, otherwise the child will die easily. The treatment method is as follows.
Amino acid and nutrition therapy: A special mixed amino acid solution of anhepatic amino acid infusion (branched chain amino acid) is dripped or dripped from nasogastric tube, and glucose (or hypertonic glucose) and electrolyte are infused from vein at the same time. The plasma leucine level of children before treatment is generally greater than 40mg/dl. Through the above treatment, plasma leucine can be rapidly reduced. Drip from nasal feeding tube has the same effect as intravenous drip.
Blood exchange: This method is to give the patient's blood to the normal person, and the normal person's blood to the patient. Normal people have the ability to handle branched-chain amino acids, and patients who transfuse blood to normal people have no adverse reactions and consequences. However, the level of leucine in the patient's blood can be reduced.