IDIOPATHIC hypervalinemia is an inborn error of valine metabolism which we found in 1963. Clinical symptoms of the patient consist of vomiting, nystagmus, hyperkinesia, muscular hypotony, failure to thrive, and mental retardation.1
Routine laboratory examinations revealed no abnormal findings. Electroencephalogram (EEG) showed an almost normal pattern at 3 months of age but sharp waves and spikes by 4 months of age.
The paper chromatography and thin-layer chromatography revealed an excessive amount of valine (Fig 1). This unusual chromatographic finding showed a good accordance with the results of quantitative determination by automatic amino acid analyzer: urinary excretion of valine was more than ten times that of controls (Table 1). There was no remarkable increase in leucine, isoleucine, or other amino acids. Serum analysis also showed an abnormally high level of valine unaccompanied by elevation of other amino acids (Table 2).
No peculiar odor was noticed in the patient's urine. Repeated
TADA K, WADA Y, ARAKAWA T. Hypervalinemia: Its Metabolic Lesion and Therapeutic Approach. Am J Dis Child. 1967;113(1):64–67. doi:10.1001/archpedi.1967.02090160114013
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