The Roentgenographic Features of Homocystinuria

In October 1962 Carson and Neill (4) reported a previously undescribed aminoaciduria, homocystinuria, that they discovered while searching for metabolic abnormalities among 2081 mentally retarded persons in Northern Ireland. The urine specimens from 2 severely retarded sisters, five and seven years old, were found to contain a sulfur-containing amino acid that they first thought was cystine. Further analysis by Dent in London showed that the amino acid was actually homocystine. Almost simultaneously Gerritsen, Vaughn, and Waisman in Wisconsin (8, 9) independently reported homocystinuria in a one-year-old male with “failure to thrive.” The basic abnormality in homocystinuria is a deficiency of the enzyme cystathionine synthetase (19), which catalyzes the condensation of homocystine and serine to form cystathionine. Patients with homocystinuria have elevated plasma levels of homocystine and, usually, of methionine (25). Only homocystine appears in the urine; it is not present in the urine of normal subjects...