Endocrine Abstracts

Introduction: 17 alpha-hydroxylase deficiency (17OHD) is a rare autosomal recessive disease caused by mutations in the CYP17A gene, representing 1% of cases of Congenital Adrenal Hyperplasia (CAH). The accumulation of mineralocorticoids and the glucocorticoid effect of corticosterone induce high blood pressure (HBP) and hypokalemia.

Clinical Case: A 44 year-old female reporting HBP since the age of 20 years and without chronic medication, presented at the emergency department (ED) complaining of generalized asthenia and polyarthralgia for about two weeks. On examination, she was hypertensive (174/100 mmHg); blood analysis revealed severe hypokalemia − K⁺ 1.2 mEq/l (3.5-5.1). In the ED, she had an episode of ventricular tachycardia evolving to asystole. After resuscitation, she was transferred to the Intensive Care Unit with rapid clinical improvement under antihypertensive therapy and hydrocortisone. Further laboratory evaluation showed: cortisol <0.4 mg/dl (3.7-19.4), ACTH 213 pg/ml (<46), aldosterone (decubitus) 27.4 ng/dl (1-16), renin <1.8 mcUI/ml (2.8-39.9). Due to these findings, she was transferred to the Endocrinology ward. On examination, she had an uncharacteristic morphotype, BMI 16.7 kg/m² (175 cm; 51.2 kg), cutaneous hyperpigmentation and Tanner stage M1P1. Hormonal evaluation showed: LH 64 mIU/ml (follicular phase 1.8-11.8), FSH 97 mIU/ml (3.03-8.08), estradiol 17 pg/ml (21-251), progesterone 5.2 ng/ml (0.1-0.3), 17-OHP 0.19 ng/ml (0.21-1.45), total testosterone 0.03 ng/ml (0.11-0.56). CT scan revealed bilateral adrenal hyperplasia (right width 11.5 mm; left width 12.9 mm) and absence of female internal genitalia (explaining primary amenorrhea referred by the patient). Genetic diagnosis was confirmed by the identification of the c.3G>A p.(Met1?) variant in homozygosity in the CYP17A1 gene. Karyotype analysis was compatible with 46 XY. At the last appointment, the patient was normotensive under dexamethasone 0.5 mg id, spironolactone 50 mg id, olmesartan 40 mg id, nifedipine 60 mg bid and nebivolol 5 mg id; blood analysis showed K+ 4.7 mEq/l and aldosterone 20.4 ng/dl.

Conclusion: The association of severe hypokalemia, hypertension, hypocortisolism, oligo/amenorrhea and the absence of secondary sexual characteristics favored the diagnosis of 17OHD, confirmed by genetic testing. As in other published cases, diagnosis outside pediatric age is not rare and should be considered in cases of severe hypokalaemia in hypertensive adults and lack of secondary sexual development.