Clinical Guidance
The clinical severity of epimerase deficiency galactosemia caused by reduced activity of the enzyme GALE ranges from potentially lethal [, , , ] to apparently benign . Epimerase deficiency galactosemia can be divided by apparent enzyme activity level in specific cell types into the following three forms: generalized, peripheral, and intermediate . Note: In all three forms, GALE enzyme activity is deficient in peripheral circulating red and white blood cells. A key difference between generalized epimerase deficiency galactosemia and intermediate or peripheral epimerase deficiency galactosemia is that individuals with generalized epimerase deficiency galactosemia develop clinical findings on a normal milk diet, while infants with peripheral or intermediate epimerase deficiency galactosemia remain clinically well, at least in the neonatal period. Generalized Epimerase Deficiency Galactosemia Generalized epimerase deficiency galactosemia is rare, with only nine individuals from five families described in the literature [, , , , , , ]. summarizes the key clinical features of individuals reported with this phenotype. Table 2. Generalized Epimerase Deficiency Galactosemia: Frequency of Select Features
Feature | # of Personsw/Feature1 | Comment |
|---|
Hepatic abnormalities | 8/9 | May be ameliorated by treatment2 |
Short stature | 7/7 | In those who survive the neonatal period |
Developmental delay | 6/6 | Incl both children who experienced acute illness before diagnosis younger sibs who were switched to a low-galactose diet before onset of severe neonatal symptoms |
Hypotonia | 6/8 | May be ameliorated by treatment2 |
Sensorineural hearing loss | 4/7 | — |
Micrognathia | 4/6 | — |
Flexion deformities of the fingers | 3/6 | — |
Hip dysplasia | 3/7 | — |
Cataracts | 3/8 | May be ameliorated by treatment2 Renal dysfunction/tubulopathy |
Source: GeneReviews — "Epimerase Deficiency Galactosemia"
