Keratosis of the palms and soles of the feet with hyperhidrosis is one of the symptoms of amino acid metabolic disease. With some exceptions, amino acid metabolic disorders are autosomal recessive and are more common in the offspring of consanguineous marriages. There are two main causes of amino acid metabolic disease, namely, deficiency of certain enzymes and impaired absorption of amino acids. The former is a known deficiency or reduction in the activity of an enzyme or an enzyme that cannot yet be identified, such as phenylalanine hydroxylase deficiency causing phenylketonuria; maple syrup urine disease caused by a deficiency or reduction in the branching amino acid alpha-keto acid decarboxylase; isovaleric acidemia caused by isovaleric coenzyme A dehydrogenase deficiency; homocystinuria caused by cystathionine synthase deficiency; argininemia caused by arginase deficiency; lysine ketone The latter is caused by amino acid reversion. The latter is caused by impaired amino acid reversion and absorption, often due to impaired absorption of certain amino acids by the intestine or other tissues, such as liver-brain-kidney (Lowe) syndrome and Hartnup disease. There are more than 100 hereditary diseases caused by amino acid metabolism disorders, and the number of new discoveries will continue to increase with the advances in biochemical detection technology. Amino acid metabolic disorders can often lead to neurological dysfunction. When the nervous system is involved, only mild psychomotor retardation is usually present, and symptoms are not apparent until 2 to 3 years after onset. Like other inherited metabolic disorders, amino acid disorders do not affect fetal in utero growth, development or delivery and may be asymptomatic in early life. The main clinical features are normal appearance and activity at birth and progressive mental retardation after six months or one year of age. After a combination of appropriate amino acid supplementation, diet control, and vitamins, neurological symptoms can improve in many cases.