Motor and Speech Disorders in Classic Galactosemia

Purpose To test the hypothesis that children with classic galactosemia and speech disorders are at risk for co-occurring strength and coordination disorders. Method This is a case–control study of 32 children (66% male) with galactosemia and neurologic speech disorders and 130 controls (50% male) ages 4–16 years. Speech was assessed using the Percentage of Consonants Correct (PCC) metric from responses to the Goldman-Fristoe Test of Articulation-2 and from a 5-min recorded speech sample, hand and tongue strength using the Iowa Oral Performance Instrument, and coordination using the Movement Assessment Battery for Children. The number of days on milk during the neonatal period was obtained by parent report. Analyses of covariance, distributions, and correlations were used to evaluate relationships among speech, strength, coordination, age, gender, and days on milk. Results Children with galactosemia had weaker hand and tongue strength and most (66%) had significant coordination disorders, primarily affecting balance and manual dexterity. Among children with galactosemia, children with more speech errors and classified as childhood apraxia of speech (n = 7) and ataxic dysarthria (n = 1), had poorer balance and manual dexterity, but not weaker hand or tongue strength, compared to the children with fewer speech errors. The number of days on milk during the neonatal period was associated with more speech errors in males but not in females. Conclusion Children with galactosemia have a high prevalence of co-occurring speech, coordination, and strength disorders, which may be evidence of a common underlying etiology, likely associated with diffuse cerebellar damage, rather than distinct disorders

Voice disorders in children with classic galactosemia

Children with classic galactosemia are at risk for motor speech disorders resulting from disruptions in motor planning and programming (childhood apraxia of speech or CAS) or motor execution (dysarthria). In the present study of 33 children with classic galactosemia, 21% were diagnosed with CAS, 3% with ataxic dysarthria, and 3% with mixed CAS-dysarthria. Voice disorders due to laryngeal insufficiency were common in children with dysarthria and co-occurred with CAS. Most (58%) of the children with classic galactosemia had decreased respiratory-phonatory support for speech, and 33% had disturbed vocal quality that was indicative of cerebellar dysfunction. Three children, two diagnosed with CAS and one not diagnosed with a motor speech disorder, had vocal tremors. Treatment of voice dysfunction in neurogenic speech disorders is discussed

Language production and working memory in classic galactosemia from a cognitive neuroscience perspective: future research directions

Most humans are social beings and we express our thoughts and feelings through language. In contrast to the ease with which we speak, the underlying cognitive and neural processes of language production are fairly complex and still little understood. In the hereditary metabolic disease classic galactosemia, failures in language production processes are among the most reported difficulties. It is unclear, however, what the underlying neural cause of this cognitive problem is. Modern brain imaging techniques allow us to look into the brain of a thinking patient online - while she or he is performing a task, such as speaking. We can measure indirectly neural activity related to the output side of a process (e.g. articulation). But most importantly, we can look into the planning phase prior to an overt response, hence tapping into subcomponents of speech planning. These components include verbal memory, intention to speak, and the planning of meaning, syntax, and phonology. This paper briefly introduces cognitive theories on language production and methods used in cognitive neuroscience. It reviews the possibilities of applying them in experimental paradigms to investigate language production and verbal memory in galactosemia

The adult galactosemic phenotype

BackgroundClassic galactosemia is an autosomal recessive disorder due to galactose‐1‐phosphate uridyltransferase (GALT) deficiency. Newborn screening and early treatment do not completely prevent tremor, speech deficits, and diminished IQ in both sexes and premature ovarian insufficiency (POI) in women. Data on how individuals with galactosemia fare as adults will improve our ability to predict disease progression.MethodsThirty‐three adults (mean age = 32.6 ± 11.7 years; range = 18–59) with classic galactosemia, confirmed by genotype and undetectable GALT enzyme activity, were evaluated. Analyses assessed associations among age, genotype, clinical features and laboratory measures.ResultsThe sample included 17 men and 16 women. Subjects exhibited cataracts (21%), low bone density (24%), tremor (46%), ataxia (15%), dysarthria (24%), and apraxia of speech (9%). Subjects reported depression (39%) and anxiety (67%). Mean full scale IQ was 88 ± 20, (range = 55–122). All subjects followed a dairy‐free diet and 75–80% reported low intake of calcium and vitamin D. Mean height, weight and body mass were within established norms. All female subjects had been diagnosed with POI. One woman and two men had had children. Logistic regression analyses revealed no associations between age, genotype or gender with IQ, tremor, ataxia, dysarthria, apraxia of speech or anxiety. Each 10‐ year increment of age was associated with a twofold increase in odds of depression.ConclusionsTaken together, these data do not support the hypothesis that galactosemia is a progressive neurodegenerative disease. However, greater attention to depression, anxiety, and social relationships may relieve the impact of this disorder in adults