Lyso-Gb3 in a Fabry pediatric cohort diagnosed by newborn screening

Purpose: Fabry disease (FD), an X-linked lysosomal storage disorder caused by the deficiency of α-galactosidase A, results in the accumulation of globotriaosylceramide and its deacylated derivative globotriaosylsphingosine (lyso-Gb3). Little is known about lyso-Gb3 levels in pediatric population identified through neonatal screening. This study evaluated levels of lyso-Gb3 at birth and during childhood. Methods: Plasma lyso-Gb3 levels were monitored annually in 25 males with FD identified by newborn screening. Long-term clinical follow-up was extended up to a maximum of 9 years of age. Results: A total of 105 plasma samples were collected. For 14 patients with later-onset (LO) variants, 53 lyso-Gb3 values were collected, 50 of which were elevated (mean 2.87 nmol/L, SD 3.46, nv