Newborn metabolic screening: a search for "nature's experiments"

Developmental timing of exposure to elevated levels of phenylalanine is associated with ADHD symptom expression

This study addresses attention deficit hyperactivity disorder (ADHD), with a focus on how the timing of a known biological insult affects ADHD symptom expression. The sample consists of children exposed to elevated levels of phenylalanine, either postnatally as in Phenylketonuria (PKU; n = 46) or prenatally as in Maternal PKU (MPKU; n = 15). Non-hyperphenylalaninemic siblings of children with PKU (n = 18) serve as controls. Results indicate that elevated levels of phenylalanine are associated with ADHD symptoms. The manifestations of the symptom expression are dependent on exposure timing: prenatal exposure is associated with a higher likelihood of expressing hyperactive/impulsive symptoms and postnatal exposure is associated with a higher likelihood of expressing inattentive symptoms. This toxicity is dose-dependent and higher levels of phenylalanine appear more detrimental.

Incidence and features of galactosaemia in Saudi Arabs

Over a 12-year period (1983 to 1994), 11 cases of classical galactosaemia were identified in the Saudi Aramco Medical Services Organization (SAMSO). This yields an incidence of 12 cases per 100,000 live births in the Easter Province of Saudi Arabia. A higher proportion of infants presented with infections compared to reports in the literature. Screening for galactosaemia is highly recommended in this high-risk population.