Variation in serum adrenal hormones in female 21-hydroxylase deficient patients.

During everyday, clinical practice hormone levels in adult female patients with 21-hydroxylase deficiency showed a moderate to excellent repeatability, despite considerable variation in time of day for blood sample collection. We found no major predictors of hormone level variation. Future studies are needed to address the relationship between the timing of glucocorticoid intake vs adrenal hormone levels and clinical outcome in both adults and children.