46XX-17α-羟化酶缺乏症助孕成功1例

Successful assisted reproductive technology treatment for a woman with 46XX-17α-hydroxylase deficiency:A case report

先天性肾上腺皮质增生症(congenital adrenal hyperplasia,CAH)是一类常染色体隐性遗传病,其中17α-羟化酶缺乏症(17α-hydroxylase deficiency,17α-OHD)为CAH少见类型。17α-OHD为CYP17基因突变所致,导致17α-羟化酶部分或完全缺乏,体内不能生成足够的皮质醇及性激素,表现为促肾上腺皮质激素(adrenocorticotropic hormone,ACTH)分泌过多,雌二醇(estradiol,E2)和雄激素降低,孕酮(progesterone,P)、促卵泡生成素(follicle stimulating hormone,FSH)和黄体生成素(luteinizing hormone,LH)升高。患者社会性别多为女性,按照染色体核型可分为46XX和46XY,其中46XX型更少见。临床表现为低血钾和高血压,46XX型患者可出现月经不规律、闭经和不孕。患者症状轻重可因17α-羟化酶缺乏程度不同而异,部分性17α-OHD患者因症状不典型,易漏诊或误诊。染色体核型为46XX的部分性17α-OHD患者可有不同程度内外生殖器官的发育和月经来潮,具备潜在排卵和生育机会,但由于体内高P水平对子宫内膜的不良影响,患者存在不孕的问题。目前关于46XX-17α-OHD助孕治疗的报道国外仅见4例,国内曾有文献报道2例,但未提及其助孕过程。北京大学第三医院生殖医学中心1例46XX-17α-羟化酶缺乏症患者经过体外受精-胚胎移植技术(in vitro fertilization-embryo transfer,IVF-ET)治疗后成功受孕并分娩。首先给予患者糖皮质激素治疗降低P水平,随后采用超长方案促排卵,获卵10枚,冻存胚胎6枚。促性腺激素释放激素激动剂(gonadotropin releasing hormone agonist,GnRH-a)降调节人工周期解冻移植后,患者成功妊娠并于妊娠37周剖宫产分娩1名健康男婴。本例患者的诊治过程提示,46XX-17α-OHD患者可以有良好的卵母细胞和胚胎,IVF联合人工周期解冻移植可以是此类患者助孕的有效方法。

Congenital adrenal hyperplasia(CAH) is an autosomal recessive disorder, and 17α-hydroxylase deficiency(17α-OHD) is a rare type of CAH. 17α-OHD is caused by CYP17 gene mutation, resulting in partial or complete deficiency of 17α-hydroxylase, which in turn leads to the lack of cortisol and sex hormone production. The disease is manifested by excessive secretion of adrenocorticotropic hormone(ACTH), decreased levels of estradiol(E2) and androgen, elevated levels of proges-terone(P), follicle stimulating hormone(FSH), and luteinizing hormone(LH). Most of the patients are female in gender. According to the chromosome karyotype, 17α-OHD can be divided into 46 XX and 46 XY, of which 46 XX is rarer. The clinical manifestations are hypokalemia and hypertension. Patients with 46 XX-karyotype may have irregular menstruation, amenorrhea, and infertility. The severity of symptoms varies according to the degree of 17α-hydroxylase deficiency. Due to its untypical manifestation, the patients with partial 17α-OHD are more likely to be missed or misdiagnosed. Some 17α-OHD patients with 46, XX karyotypes have different degrees of development of internal and external reproductive organ and spontaneous menstrual cycle, so they may have the potential ovulation and fertility opportunities. However, due to the adverse effects of high serum P level on the endometrium, the patients would have infertility problems. To date, four cases from foreign countries have been reported about the infertility treatments among 46 XX-17α-OHD patients, and two cases were mentioned in China without describing the process of treatments. Here, one case with partial 46 XX-17α-OHD was diagnosed and successfully conceived and delivered after in vitro fertilization-embryo transfer(IVF-ET) in the Center for Reproductive Medicine, Peking University Third Hospital. Controlled ovarian stimulation with ultra-long protocol was initiated after glucocorticoid therapy was given to reduce P level. Ten oocytes were obtained and 6 embryos were cryopreserved. Frozen-thawed embryo transfer under hormonal replacement after gonadotropin releasing hormone agonist(GnRH-a) was carried out in an artificial cycle, and then the patient was successfully pregnant and delivered a healthy boy after 37 weeks of gestation by cesarean section. The treatment of this case suggests that patients with partial 46 XX-17α-OHD can obtain oocytes and embryos with good quality. IVF combined with frozen-thawed embryo transfer under artificial cycle is an effective method for patients with partial 46 XX-17α-OHD with infertility.