GALT deficiency accounts for about 95% of galactosemias. Although many mutations in the GALT gene have been documented, most cases of GALT deficiency are accounted for by a few high frequency mutations. In about 5% of cases of galactosemia, the metabolic defect is in galactokinase (GALK), and very rarely, the defect is found to be in uridyl diphosphate galactose epimerase (GALE).
Because the diagnosis and therapy of this disorder is complex, the pediatrician is advised to manage the patient in close collaboration with a consulting pediatric metabolic disease specialist. It is recommended that parents travel with a letter of treatment guidelines from the patient’s physician.