Neurodevelopmental outcomes of duarte galactosemia: an exploration of cognitive development and special needs in duarte galactosemia patients

Duarte galactosemia is a variant form of galactosemia that on average results in a reduction of the galactose-1-phosphate uridyltransferase enzyme to 25% activity. This enzyme is involved in the metabolism of galactose in the body. On the contrary, patients diagnosed with the classic form of galactosemia have a galactose-1-phosphate uridyltransferase enzyme activity of zero or near-zero. As a result, classic galactosemics are placed on galactose-restricted diets to prevent acute neonatal signs of disease that can ultimately lead to death. These diets are instituted for the rest of the patients' lives. However, even with dietary treatment, classic galactosemia patients go on to experience long-term neurodevelopmental outcomes, most notably cognitive defects and speech and language delay. Duarte galactosemia patients, as a result of their residual enzyme activity, experience much milder disease symptoms. Many specialists agree that these patients have a benign disease and therefore treatment is not consistently agreed upon nor prescribed. Most Duarte patients follow an unrestricted diet and if a diet is prescribed, it is only for the first year of life. While these patients have enough enzyme activity to prevent acute neonatal signs of disease, there is still limited information regarding any long-term neurodevelopmental outcomes in the Duarte galactosemia population. This study examined developmental outcomes and need for special services of a sample of Duarte galactosemia patients. The outcome data were compared to the general population as well as to a classic galactosemia group. A convenience cohort of clinical charts for patients seen for neuropsychological evaluations from 1978 to 2013 was reviewed. Developmental scores, neuropsychological outcomes, and need for special services for patients diagnosed with a form of galactosemia were entered into an electronic database. Recorded developmental information on twenty-two Duarte galactosemia patients were found. All of the 22 Duarte patients were found to have developmental test scores within normal range. However, 38.9% of Duarte patients containing information regarding special services were found to participate in early intervention, 71.4% of which received speech therapy. Furthermore, 22.2% of Duarte patients containing information regarding special services were found to participate in special education, and 100% of these children received speech therapy. In conclusion, despite Duarte galactosemia patients not exhibiting lower learning test scores, there was a large proportion of them participating in special services, particularly in speech therapy. This indicates some speech and language difficulties in children with Duarte galactosemia