Reduced activity of 11ß-hydroxylase accounts for elevated 17α-hydroxyprogesterone in preterms.

OBJECTIVE: To characterize the urinary steroid metabolome of neonates and infants born either at term or preterm. STUDY DESIGN: We retrospectively analyzed urinary steroid hormone metabolites determined by gas chromatography-mass spectrometry of 78 neonates and infants born at term and 83 neonates and infants born preterm (median 34 weeks of gestational age). The subjects' 11ß-hydroxylase and 21-hydroxylase activities were assessed on the basis of urinary metabolite substrate-to-product ratios. RESULTS: Preterm neonates and infants had elevated urinary concentrations of 17α-hydroxyprogesterone (17OHP) metabolites (P<.001) but lower urinary concentrations of the 21-deoxycortisol metabolite pregnanetriolone (PTO) (P<.01). One reason was lower 11ß-hydroxylase activity in preterms. We could demonstrate a correlation between low 11ß-hydroxylase activity and high urinary concentrations of 17OHP metabolites (r=0.51, P<.001) but low urinary concentrations of the 21-deoxycortisol metabolite PTO (r=-0.24, P=.03) in preterms. CONCLUSIONS: Low 11ß-hydroxylase activity may explain increased 17OHP but decreased 21-deoxycortisol metabolite excretion in preterms. Our analysis clarifies, first, why preterms have higher 17OHP levels and thus higher rates of false-positive screening results for congenital adrenal hyperplasia than do term infants, and, second, why 21-deoxycortisol or its urinary metabolite PTO is more specific than 17OHP for the diagnosis of 21-hydroxylase deficiency.

Metabolic safety of growth hormone in type 1 diabetes and idiopathic growth hormone deficiency.

OBJECTIVE: To evaluate metabolic consequences of growth hormone (GH) treatment in children with type 1 diabetes. STUDY DESIGN: This study is an analysis of metabolic changes in 37 patients with childhood-onset GH deficiency and type 1 diabetes, documented in the Diabetes Patienten Verlaufsdocumentationsystem database. Main outcome measures were changes in hemoglobin A1c and daily insulin requirements during GH therapy in children with GH deficiency and type 1 diabetes compared with a large cohort of adolescents with type 1 diabetes. RESULTS: Thirty-seven patients with type 1 diabetes and a diagnosis of idiopathic GH deficiency after onset of diabetes were compared with 48856 patients with type 1 diabetes. After adjustment for age, sex, duration of diabetes, and migration background, a significant difference in mean daily insulin requirement was seen between the 2 groups (1.0 IU/kg/day in subjects with GH deficiency and type 1 diabetes vs 0.85 IU/kg/day in controls; P < .01) and height-SDS (-2.0 in subjects with GH deficiency and diabetes vs +0.03 in controls; P < .0001). There was no significant between-group difference in hemoglobin A1 concentration, however (8.1% ± 1.4% in patients with GH deficiency and type 1 diabetes vs 8.2% ± 1.7% in those with type 1 diabetes only; P > .05). CONCLUSION: An increased daily insulin requirement should be considered in patients with type 1 diabetes treated with GH. With adequate adaptation of insulin dosage, metabolic control is not impaired during GH treatment.