Miller W L
Department of Pediatrics, Child Health Research Center, University of California, San Francisco, USA.
J Urol. 1999 Aug;162(2):537-40.
Congenital adrenal hyperplasia (CAH) due to steroid 21-hydroxylase deficiency is a common cause of genital virilization in female infants resulting from inappropriate fetal adrenal androgen secretion. Some investigators have advocated treating pregnant women who are at risk for carrying a CAH fetus with dexamethasone to suppress fetal adrenal androgen synthesis. Experience to date shows that this treatment can be effective in ameliorating the genital virilization in female fetuses. However, the doses used are supraphysiological, the mechanism of dexamethasone action in the fetus is unclear and no long-term followup studies have been done. To be effective the treatment would need to be started by week 6 of gestation but the genetic diagnosis cannot be made until week 12. If the mother has had a previous CAH child, only 1 in 4 pregnancies will be affected and only the female fetuses stand to benefit from treatment, thus, 7 of 8 fetuses will be treated needlessly. In view of these and other concerns, the prenatal treatment of CAH remains an experimental therapy and, hence, must only be done with fully informed consent in controlled prospective trials approved by human experimentation committees at centers that see enough of these patients to collect meaningful data.
因类固醇21-羟化酶缺乏所致的先天性肾上腺皮质增生症（CAH）是女婴生殖器男性化的常见原因，这是由于胎儿肾上腺雄激素分泌不当所致。一些研究人员主张用地塞米松治疗有生育患CAH胎儿风险的孕妇，以抑制胎儿肾上腺雄激素的合成。迄今为止的经验表明，这种治疗可有效改善女胎的生殖器男性化。然而，所使用的剂量是超生理剂量，地塞米松在胎儿中的作用机制尚不清楚，且尚未进行长期随访研究。要使治疗有效，需要在妊娠第6周前开始，但直到第12周才能做出基因诊断。如果母亲曾生育过患CAH的孩子，那么每4次怀孕中只有1次会受到影响，且只有女胎有望从治疗中获益，因此，8个胎儿中有7个将接受不必要的治疗。鉴于这些及其他问题，CAH的产前治疗仍是一种实验性疗法，因此，必须仅在由有足够数量此类患者以收集有意义数据的中心的人体实验委员会批准的对照前瞻性试验中，并在获得充分知情同意的情况下进行。
