The purpose of this study was to identify the C11-oxy C19 and C11-oxy C21 steroids in male and female neonate plasma. At birth, the most abundant C11-oxy steroids detected in neonatal plasma were 11β-hydroxyandrostenedione, ∼13 nM, and 11-ketoprogesterone, ∼23 nM. C11-oxy C19 steroids were higher than C19 steroids in neonatal plasma, 22.2 nM vs 5.4 nM. The inclusion of C11-oxy C19 and C21 steroid reference ranges in routine steroid analyses will assist the characterization of disorders associated with impaired steroidogenic enzyme expression and the identification of potential biomarkers.
du Toit, T., Finken, M. J. J., Hamer, H. M., Heijboer, A. C., & Swart, A. C. (2018). C11-oxy C19 and C11-oxy C21 steroids in neonates: UPC2-MS/MS quantification of plasma 11β-hydroxyandrostenedione, 11-ketotestosterone and 11-ketoprogesterone. Steroids, 138, 1-5. https://doi.org/10.1016/j.steroids.2018.06.003