Maple diabetes is an autosomal recessive disorder of branched-chain amino acid metabolism due to a defective function of the branched-chain alpha keto acid dehydrogenase multienzyme complex within the cellular mitochondrial matrix. The major branched-chain amino acids in humans are leucine, isoleucine and valine, which cannot be synthesized in the body and are mainly consumed from the diet. Like other amino acids, branched-chain amino acids can be used as components of protein synthesis and can also be metabolized to produce energy. Now let’s see what are the symptoms of maple diabetes? 1, classic (neonatal type) The infant is normal within 24h after birth, but after 1 week, symptoms of ketoacidosis appear, manifested as feeding difficulties, vomiting, metabolic acidosis and neurological impairment manifestations. Such as convulsions, increased muscle tone and even muscle tonicity in the form of coracoacusis, or alternating increased muscle tone and relaxation, drowsiness or coma. Patients may have hypoglycemia, but convulsions and coma are not caused by hypoglycemia, because these symptoms do not improve after the correction of hypoglycemia. If not properly diagnosed and treated, patients often die within weeks or months, mostly from ketosis. Classic is the most severe and most common type of maple diabetes. Even if they survive with treatment, they can have sequelae of mental retardation and neurological damage. 2.Intermittent type has normal early development and is not unresponsive, from about 10 months to 2 years of age, often triggered by stressful situations, such as surgery, infection and frequent vomiting. The attacks include anorexia, vomiting, apathy, unsteady gait, ataxia, lethargy, and behavioral changes. The duration of the disease varies and can have multiple ups and downs. The residual BCKD complex activity is higher in this type of patient than in the typical type, and 8% to 10% of patients can be close to normal, so the symptoms are mild, and severe cases can also die after an attack. In intermittent episodes, the blood and urine concentrations of branched-chain amino acids increase, with hypoglycemia, hypokalemia, hyperammonemia, ketosis and acidosis, and the T2 phase shows high signal changes in the pallidum bilaterally on MRT. This type accounts for about 20% of cases. 3, intermediate type There is also maple sugar odor and mild symptoms in the urine during the neonatal period, and later on maple diabetes is induced when suffering from other diseases. The symptoms and signs of neurological involvement are mainly the same as those of classical type, but lighter, and respond to treatment with high doses of vitamin B1. 4.Lighter manifestation of mental retardation, but no other typical neurological signs and symptoms, and no intermittent episodes. 5.Vitamin B (thiamin)-responsive type Vitamin B1 is a coenzyme of BCKD complex, and when the activity of BCKD complex is reduced due to mutation of E1, E2 and E3 genes, a large amount of coenzyme composed mainly of thiamin pyrophosphate is required. Clinical manifestations are also mild, and it takes 3 weeks of treatment with high-dose (200 mg/24h) vitamin B1 to show efficacy, but there are infant patients who are effective with as little as 110 mg of vitamin B. 6, dihydrolipid acyl dehydrogenase (E3) deficiency type This type due to BCKD complex-specific kinase deficiency, this kinase is common to all α-keto acid dehydrogenase complex, so in addition to BCKD complex activity is reduced, there is also pyruvate dehydrogenase and α-ketoglutarate dehydrogenase function is impaired and cause organic acidosis in newborns, the child is born normal, and then the whole body flaccid, hypotonia, progressive ataxia and severe ataxia. The child is born normal and later develops generalized flaccidity, hypotonia, progressive ataxia, and severe neurological signs and symptoms. In this type of child, restriction of protein and fat intake and treatment with high doses of VB1 are not effective.