Biochemical investigation of young hospitalized Chinese children: results over a 7-year period.

During the seven years from January 1989 to December 1995, we investigated 2,269 Chinese infants and young children for metabolic disorders in Hong Kong. These young patients, all aged under 4 years and originated from southern China, were ill with no apparent cause and had clinical manifestations suggestive of inherited metabolic diseases. A spot urine and a plasma sample were obtained from each patient for biochemical analysis, including urinary organic acid identification and plasma amino acid analysis. Six cases of mucopolysaccharidosis, four multiple carboxylase deficiency, three 2-methylacetoacetyl CoA thiolase deficiency, two methymalonic aciduria, one glutaric aciduria type I, one glutaric aciduria type II, one a-oxoglutaric aciduria, and one case of orotic aciduria were detected. There were also single suspected cases of medium-chain acyl-CoA dehydrogenase deficiency and isovaleric aciduria. No primary amino acid disorder, such as phenylketouria and maple syrup urine disease, has been detected. Our results suggest that a different pattern of inherited metabolic diseases exists in the southern Chinese when compared with the Chinese in other regions of China.