Urinary GC-MS steroid metabotyping in treated children with congenital adrenal hyperplasia

Abstract

Abstract Background Treatment of children with classic congenital adrenal hyperplasia (CAH) is a difficult balance between hypercortisolism and hyperandrogenism. Biochemical monitoring of treatment is not well defined. Objective Cluster analysis of the urinary steroid metabolome obtained by targeted gas chromatography–mass spectrometry (GC–MS) for treatment monitoring of children with CAH. Methods We evaluated 24-h urinary steroid metabolome analyses of 109 prepubertal children aged 7.0 ± 1.6 years with classic CAH due to 21-hydroxylase deficiency treated with hydrocortisone and fludrocortisone. 24-h urinary steroid metabolite excretions were transformed into CAH-specific z-scores. Subjects were divided into groups (metabotypes) by k-means clustering algorithm. Urinary steroid metabolome and clinical data of patients of each metabotype were analyzed. Results Four unique metabotypes were generated. Metabotype 1 (N = 21 (19%)) revealed adequate metabolic control with low cortisol metabolites (mean: −0.57z) and suppressed androgen and 17α-hydroxyprogesterone (17OHP) metabolites (−0.79z). Metabotype 2 (N = 23 (21%)) showed overtreatment consisting of a constellation of elevated urinary cortisol metabolites (0.62z) and low metabolites of androgens and 17OHP (−0.75z). Metabotype 3 (N = 32 (29%)) demonstrated undertreated patients with low cortisol metabolites (−0.69z) and elevated metabolites of androgens and 17OHP (0.50z). Metabotype 4 (N = 33 (30%)) presented patients with treatment failure reflected by unsuppressed androgen- and 17OHP metabolites (0.71z) despite elevated urinary cortisol metabolites (0.39z). Conclusion Metabotyping, which means grouping metabolically similar individuals, helps to monitor treatment of children with CAH using GC–MS urinary steroid metabolome analysis. This method allows classification in adequately-, over-, or undertreated children as well as identification of patients with treatment failure.