••• Chapter 2^ Embryology of the Genital Tract^21
❍ What is the diagnosis characterized by development of both active ovarian and testicular tissue?
True hermaphroditism.
❍ What percentage of true hermaphrodites are genetic females?
70%.
❍ What develops in the male if fusion of the urethral folds is incomplete, resulting in abnormal openings
along the inferior aspect of the penis?
Hypospadias.
❍ If the caudal portions of the Müllerian ducts fail to fuse along the entire length, what uterine anomaly
will result?
Uterus didelphys.
❍ What condition is characterized by the uterus with two horns and a common vagina?
Bicornuate uterus.
❍ What is the origin of a Gartner duct cyst?
A Gartner duct cyst results from a Wolffian duct remnant, which may be seen in the wall of the vagina or
the uterus.
❍ What is congenital adrenal hyperplasia (CAH)?
Autosomal-recessive defect in steroid biosynthesis. Karyotype is typically 46XX. Most frequent cause of ambiguous
genitalia in the newborn.
❍ Name the four enzymatic defects associated with CAH. Which is the most common?
21-hydroxylase (most common), 11b-hydroxylase, 3b-hydroxysteroid dehydrogenase, and rarely 17a-hydroxylase.
❍ What is the pathophysiology of CAH?
Lack of 21-hydroxylase (or others) → decreased production of cortisol → increased secretion of adrenocorticotropic
hormone (ACTH) → accumulation of intermediate compounds in the pathway prior to the defect such as
17-hydroxyprogesterone → conversion to adrenal androgens (DHEA) and androstenedione that is converted
peripherally to testosterone.
❍ What are the clinical manifestations?
Ambiguous genitalia (cliteromegaly and swollen labial folds), 30% salt wasting, and 5% hypertension.
❍ How is CAH diagnosed?
Increased plasma levels of 17-hydroxyprogesterone.
❍ How is 17a-hydroxylase deficiency different?
Increased ACTH causes increased aldosterone production resulting in sodium retention, hypertension, and low
potassium. Potentially life threatening at birth if not recognized.