Diurnal 11-ketotestosterone and 17-hydroxyprogesterone saliva profiles in paediatric classical congenital adrenal hyperplasia

Objectives The most suitable biochemical markers for therapy adjustment in patients with congenital adrenal hyperplasia are controversial. 11-Oxygenated androgens are a promising new approach. The objective of this study was to investigate the diurnal rhythm of 11-ketotestosterone in children and adolescents in saliva and to correlate it with salivary 17-hydroxyprogesterone. Methods Fifty-one samples of steroid day-profiles from 17 patients were additionally analysed for 11-ketotestosterone, retrospectively. All patients were treated in our university outpatient clinic for paediatric endocrinology between 2020 and 2022. Steroid day-profiles of 17 patients could be examined. The cohort showed a balanced sex ratio. The median age was 13 years. The measurements for 17-hydroxyprogesterone were carried out during routine care by immunoassay. The measurements of 11-ketotestosterone were performed from frozen saliva samples using an implemented in-house protocol for liquid chromatography - tandem mass spectrometry (LC-MS/MS). The most important outcome were the absolute values for 11-ketotestosterone, their diurnal rhythmicity and the correlation with 17-hydroxyprogesterone. Results Both steroids show a circadian diurnal rhythm. 17-hydroxyprogesterone and 11-ketotestosterone correlate significantly. 11-Ketotestosterone showed a positive correlation with BMI at all times of the day. Conclusions 11-Ketotestosterone shows circadian rhythmicity in our cohort and correlates with 17-hydroxyprogesterone. These findings serve as an important basis for prospective research into 11-oxygenated androgens as therapeutic markers in paediatrics. However, 11-ketotestosterone appears to be very dependent on BMI.