What Are the Long-Term Cognitive Effects of Galactosemia?

Patient Presentation
A 4-year-old female came to clinic to establish care as she had recently moved. She was known to have galactosemia that was diagnosed and treatment begun within days of birth. Overall she had done well but was receiving speech therapy and the parents related that she was a “little behind” other children in general. The parents had previously been told that she would probably need some specific help academically. She had no other medical problems.

The pertinent physical exam showed a well-developed female with normal growth parameters, vital signs and normal examination.
The diagnosis of a well-child with galactosemia was made. She already had an appointment with the local geneticist for continued monitoring. A referral was made for continued speech therapy as well as the local school system to start discussing her educational needs and a referral to a developmental pediatrician to better assess her overall developmental needs. The patient’s clinical course showed that developmental testing by the school and developmental pediatrician had low-normal cognition and communication problems. A developmental preschool placement was recommended to help with her communication skills in a supportive social and academic environment, and she currently likes the program.

Discussion
Galactosemia is a disorder caused by the galactose-1-phosphate deficiency. It is an autosomal recessive disorder resulting from an abnormality of the GALT gene on chromosome 9. There is an incidence of 1:47,000 in the white population. Treatment with lactose-free diets is the mainstay. Lactose is a disaccaride composed of glucose and galactose. Neonates if untreated usually present early with hepatotoxicity (jaundice, hepatosplenomegaly, hypoglycemia), failure to thrive, emesis, hypotonia, renal tubular dysfunction, sepsis, and cataracts. Despite adequate or good compliance with diets longer term problems continue and their cause and potential amelioration still remains elusive. Longer term problems include: cognitive, social, and communication problems. Most females also develop hypergonadotroic hypogonadism and fertility problems. Patient may also have motor problems.

Learning Point
Cognition studies of galactosemia patients mainly have been cross-sectional and usually show an overall decrease in cognitive function relative to those without galactosemia, with some continued decrease in cognition with aging. Areas of cognition affected include IQ, memory, and executive functioning. However, there are large interindividual differences and few longitudinal studies.

One study in Germany that evaluated individual patients for IQ at 3 times (means 11, 13.6 and 26 years) found that individual’s IQ basically stayed the same over time. Also there were 2 clusters of individuals: those with higher IQ scores continued to have higher IQ scores and those with lower scores continued to have lower scores. The authors looked for potential mechanisms such as time to treatment, treatment compliance, etc. but were not able to identify one and postulate that potential in utero exposure may be part of the cause.

Another study in England evaluated older patients (15-51 years) and found overall lower cognition but with large individual variability. Their data also showed educational attainment correlated with cognitive performance. A health-related quality of life study showed similar results. Galactosemic patients themselves and their parents were surveyed and compared to healthy peers. Patients 1-5 years had more communication and abdominal complaints, those 8-15 years differed in cognitive function and those 16 years and older differed in cognitive function and social function. The overall educational attainment by the galactosemic patients was significantly less than the general population.

Questions for Further Discussion
1. What services in the local community are availble for patients and families with metabolic disorders?
2. What types of foods contain galactose?

Related Cases

To Learn More
To view pediatric review articles on this topic from the past year check PubMed.

Evidence-based medicine information on this topic can be found at SearchingPediatrics.com, the National Guideline Clearinghouse and the Cochrane Database of Systematic Reviews.

Information prescriptions for patients can be found at MedlinePlus for this topic: Metabolic Disorders

To view current news articles on this topic check Google News.

To view images related to this topic check Google Images.

Bosch AM, Grootenhuis MA, Bakker HD, Heijmans HS, Wijburg FA, Last BF. Living with classical galactosemia: health-related quality of life consequences. Pediatrics. 2004 May;113(5):e423-8.

Doyle CM, Channon S, Orlowska D, Lee PJ. The neuropsychological profile of galactosaemia. J Inherit Metab Dis. 2010 Oct;33(5):603-9.

Schadewaldt P, Hoffmann B, Hammen HW, Kamp G, Schweitzer-Krantz S, Wendel U. Longitudinal assessment of intellectual achievement in patients with classical galactosemia. Pediatrics. 2010 Feb;125(2):e374-81.

Galactosemia. Online Mendelian Inheritance in Man. Available from the Internet at http://omim.org/entry/230400 (rev. 9/30/11, cited 1/9/13).

ACGME Competencies Highlighted by Case

  • Patient Care
    1. When interacting with patients and their families, the health care professional communicates effectively and demonstrates caring and respectful behaviors.
    2. Essential and accurate information about the patients’ is gathered.
    3. Informed decisions about diagnostic and therapeutic interventions based on patient information and preferences, up-to-date scientific evidence, and clinical judgment is made.
    4. Patient management plans are developed and carried out.
    7. All medical and invasive procedures considered essential for the area of practice are competently performed.
    8. Health care services aimed at preventing health problems or maintaining health are provided.
    9. Patient-focused care is provided by working with health care professionals, including those from other disciplines.

  • Medical Knowledge
    10. An investigatory and analytic thinking approach to the clinical situation is demonstrated.
    11. Basic and clinically supportive sciences appropriate to their discipline are known and applied.

  • Systems Based Practice
    25. Quality patient care and assisting patients in dealing with system complexities is advocated.
    26. Partnering with health care managers and health care providers to assess, coordinate, and improve health care and how these activities can affect system performance are known.

    Author

    Donna M. D’Alessandro, MD
    Professor of Pediatrics, University of Iowa Children’s Hospital