Homma Keiko, Hida Mariko, Ikeda Kazushige, Yamaga Nobuo, Murata Mitsuru, Hasegawa Tomonobu
Central Clinical Laboratories, Keio University Hospital, Tokyo, Japan.
Clin Pediatr Endocrinol. 2009 Jul;18(3):77-80. doi: 10.1297/cpe.18.77. Epub 2009 Aug 1.
Immunochemical measurement of serum 17α-hydroxyprogesterone (17OHP), the most important parameter for diagnosis of classical 21-hydroxylase deficiency (21OHD) in newborn infants, is known to be inaccurate due to the cross-reactivity of antibodies with a large quantity of fetal adrenal steroids. The aims of this study were 1) to establish reference values for the serum 17OHP level in Japanese newborn infants using non-immunochemical stable isotope dilution -gas chromatography/mass spectrometry (SID-GC/MS) and 2) to compare the serum 17OHP levels determined by SID-GC/MS with those determined by radioimmunoassay (RIA). The first study subjects were used for determination of reference values and included 57 healthy full-term newborn infants (4-5 d of age). The second study subjects were used for comparison of SID-GC/MS with RIA and included 27 healthy full-term newborn infants (3-6 d of age) and two subjects with neonatal transient hyper 17OHPnemia; these two subjects were 16 and 27 d of age, respectively. In the first study subjects, the intra-assay coefficient of variation for SID-GC/MS was 3% (n=5), the recovery rate was 98%, the sensitivity was 0.2 ng/ml, and the range of linearity was 0.5-200 ng/ml. The reference values for the serum 17OHP level determined by SID-GC/MS ranged from 0.3-1.5 (0.6) (ng/ml) (median). In the second study subjects, the serum 17OHP levels determined by SID-GC/MS were lower in one of the 27 subjects and both of the two subjects with neonatal transient hyper 17OHPnemia compared with the levels determined by RIA. Measurement of the serum 17OHP level using SID-GC/MS may be clinically useful for definitive diagnosis of classical 21OHD in newborn infants.
血清17α-羟孕酮（17OHP）的免疫化学测定是新生儿经典21-羟化酶缺乏症（21OHD）诊断的最重要参数，但由于抗体与大量胎儿肾上腺类固醇的交叉反应，该测定方法已知不准确。本研究的目的是：1）使用非免疫化学稳定同位素稀释-气相色谱/质谱法（SID-GC/MS）建立日本新生儿血清17OHP水平的参考值；2）比较通过SID-GC/MS测定的血清17OHP水平与通过放射免疫分析（RIA）测定的水平。第一项研究的对象用于确定参考值，包括57名健康足月儿（4-5日龄）。第二项研究的对象用于比较SID-GC/MS与RIA，包括27名健康足月儿（3-6日龄）和两名新生儿暂时性高17OHP血症患者；这两名患者分别为16日龄和27日龄。在第一项研究对象中，SID-GC/MS的批内变异系数为3%（n=5），回收率为98%，灵敏度为0.2 ng/ml，线性范围为0.5-200 ng/ml。通过SID-GC/MS测定的血清17OHP水平参考值范围为0.3-1.5（0.6）（ng/ml）（中位数）。在第二项研究对象中，与RIA测定的水平相比，27名受试者中的1名以及两名新生儿暂时性高17OHP血症患者中的两名通过SID-GC/MS测定的血清17OHP水平较低。使用SID-GC/MS测定血清17OHP水平可能对新生儿经典21OHD的明确诊断具有临床实用性。
