Figure 1.

Metabolic screening for neurologic indications in infants. Flow chart of the data presented in the manuscript. This retrospective study included all cases of infants <1 year of age in 2017 who had metabolic screening laboratory studies performed at Hospital for Sick Children in Toronto. 324 unique cases were represented in this cohort. A total of 164 screens were performed where the primary test indication was neurologic, including hypotonia, global developmental delay, seizures, movement disorder, and stroke. In 9/164 cases overall (5.5%), metabolic screening was positive and guided diagnosis. Cases were further subdivided by whether they were sent from the inpatient (111) or outpatient (53) setting, and for the specific indication of hypotonia and/or global developmental delay. In all settings, the percentage of positive tests was extremely low. (yield = percentage of positive screens/total patients where screening metabolic studies were performed).