Refractory hypertension and hypokalemic myopathy in a phenotypic female: A case of 46, XY 17-alpha hydroxylase deficiency

Abstract

Background: 17-Alpha hydroxylase deficiency (17-OHD) is a rare form of congenital adrenal hyperplasia that presents in 46,XY individuals with failed sex steroid synthesis, a female external phenotype, and accumulation of mineralocorticoid precursors causing hypertension and hypokalemia.

Case summary: We report a 21-year-old phenotypically female patient who presented with refractory hypertension and profound muscle weakness. Laboratory evaluation revealed severe hypokalemia (1.80 mmol/L) and markedly elevated creatine phosphokinase (3876 U/L), diagnostic of hypokalemic myopathy. Endocrine profiling showed suppressed renin (2.2 µIU/ml) and aldosterone (22.2 pg/mL) with elevated ACTH (152 pg/mL); hypergonadotropic gonadotropins (FSH 33.23 IU/L, LH 48.52 IU/L); significantly elevated progesterone (7.61 ng/mL); very low testosterone (<7.00 ng/dL) and estradiol (22.27 pg/mL); and markedly elevated 11-deoxycorticosterone (323 ng/dl), consistent with a mineralocorticoid-excess state. Cytogenetic analysis demonstrated a 46,XY karyotype with absent uterus and ovaries on ultrasonography, confirming 46,XY disorder of sex development; molecular analysis of CYP17A1 is pending. Potassium and CPK levels normalized rapidly following potassium replacement and glucocorticoid therapy.

Conclusion: This case exemplifies the classic mineralocorticoid-excess presentation of 17-OHD, in which elevated deoxycorticosterone drives sodium retention and renal potassium wasting, precipitating an acute myopathy often misdiagnosed as primary neuromuscular disease. 17-OHD should be considered in any phenotypic female presenting with refractory hypertension, severe hypokalemia, and primary amenorrhea, as prompt diagnosis via steroid profiling and karyotyping is essential to manage cardiovascular risk and guide long-term hormone replacement and gender-affirming care.

[J Assoc Clin Endocrinol Diabetol Bangladesh, 2026;5(Suppl 1): S52]