Deficiencies in Testosterone Biosynthesis
October 30, 2007 on 10:17 am | In Gynecology | Comments OffJoe Leigh Simpson
Male pseudohermaphroditism may result from deficiencies of 17a-hydroxylase, 3b-ol-dehydrogenase, or 17-ketosteroid reductase 17,20-desmolase. These enzymes are required to convert cholesterol to pregnenolone (congenital adrenal lipoid hyperplasia). Deficiencies of 21-hydroxylase or 11b-hydroxylase, the most common causes of female pseudohermaphroditism, do not cause male pseudohermaphroditism. Males (46,XY) show precocious masculinization.
Adrenal biosynthetic defects should be suspected [...]
Male Pseudohermaphroditism in Multiple Malformation Syndromes
October 30, 2007 on 10:16 am | In Gynecology | Comments OffJoe Leigh Simpson
Genital ambiguity may occur in individuals with various multiple malformation syndromes. Coexistence of genital ambiguity with the Meckel-Gruber syndrome, Smith-Lemli-Opitz type I syndrome, brachio-skeletal-genital syndrome, and esophageal-facial-genital syndrome has long been recognized. These disorders are inherited in either autosomal recessive or X-linked recessive fashion.
Drash syndrome is an appellation applied to individuals with Wilms’ [...]
45,X/46,XY Unambiguous Female External Genitalia
October 28, 2007 on 8:46 am | In Gynecology | Comments OffJoe Leigh Simpson
45,X/46,XY individuals may have Turner’s stigmata and thus be clinically indistinguishable from 45,X individuals. Such individuals usually are normal in stature and show no somatic anomalies. As in other types of gonadal dysgenesis, the external genitalia, vagina, and müllerian derivatives remain unstimulated because of the lack of sex steroids. Breasts fail to develop, [...]
Cytogenetic Forms
October 28, 2007 on 8:43 am | In Gynecology | Comments OffJoe Leigh Simpson
45,X/46,XY individuals have both a 45,X cell line and at least one cell line containing a Y chromosome. Based on cohort studies of 45,X/46,XY cases detected without bias in utero (prenatal genetic diagnosis), well over 90% of cases are normal males. However, cases ascertained postnatally differ, manifesting a variety of phenotypes: almost normal [...]
Male Pseudohermaphroditism
October 27, 2007 on 8:43 am | In Gynecology | Comments OffJoe Leigh Simpson
In male pseudohermaphroditism, individuals with a Y chromosome have external genitalia that fail to develop as expected for normal males. This implies external genitalia sufficiently ambiguous to confuse the sex of rearing. Cytogenetic forms of male pseudohermaphroditism (45,X/46,XY and variants) are discussed here to contrast their phenotype with those of genetic male pseudohermaphroditism.
Other Forms of Female Pseudohermaphroditism
October 27, 2007 on 8:41 am | In Gynecology | Comments OffJoe Leigh Simpson
Two siblings had clitoral hypertrophy, a single perineal orifice leading anteriorly to a urethra and posteriorly to a vagina, and numerous skeletal anomalies (hypoplasia of the mandible and maxilla, brachycephaly, narrow vertebral bodies, relatively long slender bones, dislocation of fusion of the radial heads leading to abnormal-appearing elbows, coxa valga, and phalangeal fusion [...]
Teratogenic Forms
October 27, 2007 on 7:23 am | In Gynecology | Comments OffJoe Leigh Simpson
To interfere with genital differentiation, a teratogen also must exert its action during organogenesis. Before that time, no organ-specific structure can be affected. In humans, the genital tubercle first becomes evident at about 5 weeks of embryogenesis (7 weeks of gestation). If an androgenic teratogen is administered before 12 weeks of gestation, labioscrotal [...]
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