Zhu Ziyang, Ni Shining, Gu Wei
Department of Endocrinology, Nanjing Children's Hospital Affiliated to Nanjing Medical University Nanjing 210008, China.
Int J Clin Exp Med. 2015 Oct 15;8(10):19132-7. eCollection 2015.
Combined with the literature, recognize the clinical features and molecular genetic mechanism of the disease. 17a-hydroxylase/17,20-lyase deficiency, a rare form of congenital adrenal hyperplasia, is caused by mutations in the cytochrome P450c17 gene (CYP17A1), and characterized by hypertension, hypokalemia, female sexual infantilism or male pseudohermaphroditism. We presented the clinical and biochemical characterization in two patients (a 13 year-old girl (46, XX) with hypokalemia and lack of pubertal development, a 11 year-old girl (46, XY) with female external genitalia and severe hypertension). CYP17A1 mutations were detected by PCR and direct DNA sequencing in patients and their parents. A homozygous mutation c.985_987delTACinsAA (p.Y329KfsX418) in Exon 6 was found in patient 1, and a homozygous deletion mutation c.1459_1467delGACTCTTTC (p.Asp487_Phe489del) in exon 8 in patient 2. The patients manifested with hypertension, hypokalemia, sexual infantilism should be suspected of having 17a-hydroxylase/17,20-lyase deficiency. Definite diagnosis is depended on mutation analysis. Hydrocortisone treatment in time is crucial to prevent severe hypertension and hypokalemia.
结合文献，认识该疾病的临床特征和分子遗传机制。17α-羟化酶/17,20-裂解酶缺乏症是先天性肾上腺皮质增生症的一种罕见形式，由细胞色素P450c17基因（CYP17A1）突变引起，其特征为高血压、低钾血症、女性性幼稚或男性假两性畸形。我们介绍了两名患者的临床和生化特征（一名13岁女孩（46,XX），有低钾血症且青春期未发育；一名11岁女孩（46,XY），有女性外生殖器且患有严重高血压）。通过聚合酶链反应（PCR）和直接DNA测序检测患者及其父母的CYP17A1突变。在患者1中发现外显子6的纯合突变c.985_987delTACinsAA（p.Y329KfsX418），在患者2中发现外显子8的纯合缺失突变c.1459_1467delGACTCTTTC（p.Asp487_Phe489del）。对于表现为高血压、低钾血症和性幼稚的患者，应怀疑患有17α-羟化酶/17,20-裂解酶缺乏症。明确诊断依赖于突变分析。及时进行氢化可的松治疗对于预防严重高血压和低钾血症至关重要。
