Thyroxine-binding globulin deficiency in Beckwith syndrome

Abstract

swelling because of the osmotic activity of intracellular galactitol. With a block in galactose metabolism due to defective galactokinase activity, there is little or no formation of galactose-l-phosphate, so that the formation of galactitol and its excretion in the urine is the main route of galactose metabolism. ~ In classic galactosemia resulting from galactose-l-phosphate uridyl transferase deficiency, in which mental retardation and other symptoms are regularly seen in untreated patients, there is the accumulation of galactose-1-phosphate in addition to galactitol. It has been reasonable to assume that the symptoms other than cataracts are a consequence of the formation of large amounts of galactose-1-phosphate. If the mental retardation in our patients is a manifestation of the galactokinase deficiency, then the accumulation of galactose itself or of galactitol must play an etiologic role. The complete elucidation of the clinical spectrum of galactokinase deficiency must await the observation of greater numbers of patients. Since all infants and young children with cataracts should be examined for galactokinase deficiency 1~ and, when found, treated with a galactose free diet, the number of undiagnosed older children, such as we report here, should be few. The possibility that untreated patients may be mentally retarded adds a compelling reason for maintenance of stringent dietary therapy. REFERENCES 1. Segal S: Galactosemia, in Stanbury JB, Wyngaarden JB, and Fredrickson DS, editors: The metabolic basis of inherited disease, ed 4, New York, 1978, McGraw-Hill Book Company, Inc., pp 160-181. 2. Gitzelmann R: Deficiency of erythrocyte galactokinase in a patient with galactose diabetes, Lancet 2:670, 1965. 3. Ng WG, Donnell GN, and Bergren WR: Galactokinase activity in human erythrocytes of individuals at different ages, J Lab Clin Med 66:115, 1965. 4. Ng WG, Bergren WR, and Donnell GW: An improved procedure for the assay of hemolysate galactose-l-phosphate uridyltransferase activity by the use of labeled galactose-l-phosphate, Clin Chim Acta 15:489, 1967. 5. Pickering WR, and Howell RR: Galactokinase deficiency: Clinical and biochemical findings in a new kindred, J PEDIATR 81:50, 1972. 6. Gitzelmann R: Hereditary galactokinase deficiency, a newly recognized cause of juvenile cataracts, Pediatr Res 1:14, 1967. 7. Litman N, Kanter A, and Finberg L: Galactokinase deficiency presenting as pseudotumor cerebri, J PEDIATR 86:410, 1975. 8. Cogan DD: The lens, cataracts and galactosemia, N Engl J Med 288:1240, 1973. 9. Quan-Ma R, and Wells W: The distribution ofgalactitol in tissues of rats fed galactose, Biochem Biophys Res Commun 20:486, 1965. 10. Beutler E, Matsumoto F, Kuhl W, Krill A, Levy N, Sparkes R, and Degnan M: Galactokinase deficiency as a cause of cataracts, N Engl J Med 288:1203, 1978.