Causes Patients have a disorder of cellular metabolism due to enzyme deficiency or enzyme structural defects that prevent the corresponding substrate from being degraded in the cell and stored in the secondary lysosomes. Congenital lysosomal disease is a type of metabolic genetic disease caused by the congenital deficiency of a lysosomal enzyme due to a mutation in some genes on the chromosome. It is also called lysosomal storage disease because the corresponding substrates in the cell cannot be degraded and are stored in secondary lysosomes due to enzyme deficiency or enzyme structural defects, resulting in cellular metabolic disorders. Mucopolysaccharide storage disease is a group of diseases that occur when acidic mucopolysaccharide molecules (aminoglucan) cannot be degraded due to lysosomal enzyme defects, resulting in large amounts of mucopolysaccharide deposits in tissues and increased excretion of mucopolysaccharides in urine. Examination Mucopolysaccharide storage disease is a group of diseases that occur when acidic mucopolysaccharide molecules (aminoglucan) are not degraded due to lysosomal enzyme defects, resulting in large amounts of mucopolysaccharide deposits in tissues and increased urinary mucopolysaccharide excretion. According to the clinical manifestations and enzyme defects, MPS can be divided into 6 types such as Ⅰ to Ⅶ, among which type I is divided into type ⅠH and type ⅠS, and type V has been renamed as type ⅠH/S. Except for type II, which is sex-linked recessive, the rest are autosomal recessive disorders. As with other lysosomal accumulation diseases, most of the MPS types develop around 1 year of age, and the disease course is progressive and involves multiple systems with similar clinical symptoms, but the severity of each type varies and has its own characteristics, among which type IH is the most typical and has the worst prognosis, with children often dying before 10 years of age; type IS has the mildest disease. The lesions mainly involve the skeleton, but also the central nervous system, cardiovascular system, liver, spleen, joints, tendons, skin, etc.