Pregnanetriol in the Range of 1.2–2.1 mg/m2/day as an Index of Optimal Control in CYP21A2 Deficiency

Auxological data is the gold standard index of the therapeutic condition in CYP21A2deficiency over a long-range period, whereas urinary pregnanetriol for 24 h (PT) isvariable for a shorter-range period. Ideal PT levels in comparison with auxological datahave not been reported. The main purpose of this study was to analyze ideal PT values asan index of optimal control for CYP21A2 deficiency. First, inter-daily fluctuation of PTwas analyzed in one participant. PT levels were distributed over a wide range of 0.44–14.7mg/day (n=42) in this participant, suggesting that the therapeutic condition should bejudged by multiple PT samples. Second, the therapeutic periods of 15 participants withCYP21A2 deficiency were classified using auxological data and Cushing-like symptoms, andthe PT levels were analyzed in each period retrospectively. The 95% confidence intervalsfor the means of the PT levels in the excessive, good and poor control periods were0.03–1.25 (n=26), 1.23–2.09 (n=116), and 5.35–8.37 (n=72) mg/m²/day,respectively. In conclusion, 1.2–2.1 mg/m²/day of PT values can be used as anindex of optimal control in CYP21A2 deficiency.