1986 Volume 17 Issue 1 Pages 53-64
Reliability of 17α-hydroxyprogesterone (17-OHP) values determined by direct extraction with mixed solvent and enzyme immunoassy (EIA) in dried serum samples on filter paper disc (disc serum) was evaluated as a means for mass-screening of congenital adrenal hyperplasia (CAH) due to 21-hydroxylase deficiency. Furthermore, to clarify the cause of false positive cases, serum 17-OHP concentrations were followed during neonatal period in low birth weight infants and compared with normal infants and the infants with high risk disorders. Values of 17-OHP determined by EIA in disc serum were in good correlation with those determined by radioimmunoassay and 17-OHP concentrations in the same serum samples. Depending on the duration of storage, 17-OHP values in disc serum decreased gradually but were not influenced by the temperature of storage. In contrast to normal infants in whom serum 17-OHP concentrations decreased rapidly after birth, low birth weight infants tended to remain their serum 17-OHP concentrations in high level during neonatal period, particularly remarked in the infants under 1000g of body weight at birth, less than 32 weeks of fetal life or 35 weeks of equivalent gestational age. In the infants with high risk disorders showed almost as same course of serum 17-OHP concentrations after birth as normal infants. There were no significant correlations between 17-OHP, dehydroepiandrosterone-sulfate, cortisol and ACTH concentrations in the same serum samples in normal and in low birth weight infants. In conclusion : (1) estimation of 17-OHP in disc serum by direct extraction and EIA is useful for mass-screening of CAH due to 21-hydroxylase deficiency, but caution must be given to the duration of storage of samples, (2) low birth weight infants are major cause of false positive in mass-screening of CAH due to 21-hydroxylase deficiency because of persistent high level of 17-OHP concentration in serum during neonatal period probably through functioning fetal adrenal cortex.
