Diagnostic Criteria

Suggestive Findings

Duarte galactosemia should be suspected in an infant with an for galactosemia OR a and family history; clinical findings are not present even when on a high-galactose diet (e.g., breast milk or a dairy milk-based formula).

Infant with Out-of-Range NBS Result

NBS for classic galactosemia and its variants (including Duarte galactosemia) is primarily based on the use of dried blood spots collected between 24 and 72 hours after birth to quantify erythrocyte galactose-1-phosphate uridylyltransferase (GALT) enzyme activity and/or galactose metabolites.

Source: GeneReviews — "Duarte Galactosemia"

Differential Diagnosis

Most infants with Duarte galactosemia are identified following an out-of-range newborn screening (NBS) result for galactosemia. The differential diagnosis of out-of-range NBS for galactosemia includes Duarte galactosemia and the following:

• Classic galactosemia and clinical variant galactosemia

Source: GeneReviews — "Duarte Galactosemia"

Management Guidelines

Evaluations Following Initial Diagnosis

An infant with a confirmed diagnosis of Duarte galactosemia who presents with concerning clinical manifestations should be referred to a metabolic specialist for evaluation of another concurrent condition, since infants with Duarte galactosemia do not have clinical features of a biochemical disorder. Consultation with a certified genetic counselor to obtain a pedigree and inform individuals with Duarte galactosemia and their families about the nature, mode of inheritance, and genetic implications of a diagnosis of Duarte galactosemia is recommended.

Treatment of Manifestations

Current data suggest that infants and children with Duarte galactosemia are not at increased risk for acute , long-term developmental , or ovarian complications regardless of dietary exposure to galactose in infancy. In light of these data, most health care providers no longer recommend dietary intervention for infants with Duarte galactosemia [; JL Fridovich-Keil RH Singh, personal observations]; however, a small number of providers continue to recommend dietary restriction of galactose for individuals suspected of having Duarte galactosemia, often because the available testing is insufficient to distinguish Duarte galactosemia from other forms of galactosemia [JL Fridovich-Keil RH Singh, personal observations]. If the decision is made to restrict dietary galactose, one or more of the following may be recommended :

Source: GeneReviews — "Duarte Galactosemia"

Clinical Guidance

Some health care providers recommend avoiding all high-galactose foods (e.g., dairy milk products) for the first year of life, followed by a galactose challenge; other health care providers argue that this precaution is neither warranted nor desirable for infants with a confirmed diagnosis of Duarte galactosemia.

Source: GeneReviews — "Duarte Galactosemia"

Therapies Under Investigation

Search ClinicalTrials.gov in the US and EU Clinical Trials Register in Europe for information on clinical studies for a wide range of diseases and conditions. Note: As there are no negative health consequences documented for this condition, there may not be any clinical trials.

Source: GeneReviews — "Duarte Galactosemia"

Surveillance Guidelines

Although most metabolic specialists surveyed report that no surveillance of infants with Duarte galactosemia is needed [JL Fridovich-Keil RH Singh, personal observations], some infants with Duarte galactosemia who are given a galactose-restricted diet and followed by a genetics or metabolic specialist are discharged from follow up after a successful galactose challenge at age one year . Among children with Duarte galactosemia who experienced dietary galactose restriction in infancy, if the erythrocyte galactose-1-phosphate concentration is 1.0 mg/dL following a galactose challenge at age one year, galactose restriction may be resumed, and the galactose challenge and measurement of erythrocyte galactose-1-phosphate concentration repeated every four to six months until the erythrocyte galactose-1-phosphate concentration stabilizes at 1.0 mg/dL. If the erythrocyte galactose-1-phosphate concentration continues to rise to 1.0 mg/dL following a galactose challenge, it may be appropriate to reconsider if the diagnosis of Duarte galactosemia is correct, or if another concurrent condition is present.

Source: GeneReviews — "Duarte Galactosemia"