SUMMARY
1. Galactosemia is an autosomal recessive disease caused by a defect in galactose-1-phosphate uridyl transferase (GALT). Patients present with the following clinical features:
Jaundice
Vomiting
Poor feeding
Failure to thrive
Hepatomegaly
Developmental delay
Cataracts
2. Patients with galactosemia have an inability to break down galactose. Galactose is a sugar found primarily in human and bovine milk as part of the disaccharide lactose. Lactose is hydrolyzed to glucose and galactose by the intestinal enzyme lactase; the galactose then is converted to glucose for use as an energy source
3. Patients are at increased for fatal sepsis from E. coli during the neonatal period. Patients have impaired granulocyte chemotaxis (function is normal). Neutrophils exposed to galactose in vitro also demonstrate impaired function.
4. Newborn screening for galactosemia is performed routinely in the United States. A quantitative assay of RBC GALT activity is necessary to confirm the diagnosis of galactosemia.
OVERVIEW
Galactosemia is an autosomal recessive disease caused by a defect in galactose-1-phosphate uridyl transferase (GALT). Patients present with the following clinical features:
Jaundice
Vomiting
Poor feeding
Failure to thrive
Hepatomegaly
Developmental delay
Cataracts
Patients with galactosemia have an inability to break down galactose. Galactose is a sugar found primarily in human and bovine milk as part of the disaccharide lactose. Lactose is hydrolyzed to glucose and galactose by the intestinal enzyme lactase; the galactose then is converted to glucose for use as an energy source.
Patients are at increased for fatal sepsis from E. coli during the neonatal period. Patients have impaired granulocyte chemotaxis (function is normal). Neutrophils exposed to galactose in vitro also demonstrate impaired function.
EVALUATION
Newborn screening for galactosemia is performed routinely in the United States. A quantitative assay of RBC GALT activity is necessary to confirm the diagnosis of galactosemia.
MANAGEMENT
The treatment is immediate life-long exclusion of galactose from the diet. Infants should be started on a soy-based formula. Strict adherence to a galactose-free diet results in the resolution of clinical features and normal intellectual development.