Transient hyper-17-OHPnemia unrelated to cross-reactions with residual fetal adrenal cortex products

Objective: To clarify the pathogenesis of transient hyper-17α- hydroxyprogesteronemia, we initiated a laboratory investigation in a pre-term infant with persistently high serum 17α-hydroxyprogesterone (17-OHP) until 2 months of age. Methods: Serum 17-OHP level was measured by high-performance liquid chromatography and radioimmunoassay, and gene analysis of CYP21A2 (21-hydroxylase) was performed. Result: Serum 17-OHP level on the 29th day of life was 25.4 ng/ml, and the urinary steroid profile showed low pregnanetriolone. Gene analysis of 21-hydroxylase disclosed no mutation, and 17-OHP normalized by 3 months of age without specific treatment. Conclusion: Transient elevations in 17-OHP, which do not appear related to cross-reactions with products of a residual fetal adrenal cortex, may occur in the first few months of life.