Hyperlysinemia Associated with Retardation

Abstract

TWO unrelated patients, mentally and physically retarded, were found to have persistent hyperlysinemia and hyperlysinuria. Both patients had lax ligaments and hypotonie muscles. The metabolic anomaly was investigated through repeated quantitative analysis of biologic fluids for amino acids, administration of a loading dose of lysine and its metabolite and studies of the subsidiary pathway of lysine. The results suggested that both patients had a heretofore undescribed inborn error of lysine metabolism. This paper amplifies our previous report¹ on this condition. Another case, in many respects similar to ours, was reported by Woody.² Case ReportsCase 1. This patient was 27 . . .