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Updated: May 20, 2026
In Vivo Functional Study of Disease-associated Rare Human Variants Using Drosophila
Published on: August 20, 2019
17α-hydroxlyase/17, 20-lyase deficiency in three siblings with primary amenorrhea and absence of secondary sexual
1Department of Obstetrics and Gynecology, Samsung Medical Center, Seoul, Korea.
Background:
17α-hydroxlyase/17, 20-lyase deficiency (17OHD) is a rare phenotype of congenital adrenal hyperplasia that can cause primary amenorrhea.
Case:
Three phenotypically female siblings visited the adolescent gynecologic clinic complaining of primary amenorrhea and absence of secondary sexual developments. All had constant high blood pressure and showed a hypergonadotropic hypogonadal state with high progesterone and low testosterone levels. Two were genotypically females and one was genotypically a male; all were confirmed to have 17OHD, and estrogen replacement, glucocorticoids, and antihypertensive drugs were Prescribed to the patients.
Summary And Conclusion:
Identifying a 17OHD patient complaining of primary amenorrhea in a gynecologic clinic is important for proper management.
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