Disorders of Sex Development Flashcards
46, XX DSD
- internal genitalia
- external genitalia
- fertility
- gender assignment
- normal ovaries, uterus
- virilized
- potential to bear children
- female
can be due to exposure of exogenous androgens through mother
46, XY DSD
- internal genitalia
- external genitalia
- fertility
- gender assignment
- wolffian structures can be normal, hypo plastic, or absent; no mullerian structures
- under-virilized
- ?
- male, exception: complete androgen resistance, completely feminized genitalia, family decision
low: testosterone
What are the types of gender reassignment surgeries?
Which is easier to do?
- reduction of size of phallus, creation of vagina (easier)
2. constructing a phallus
steroidogenic factor 1 (SF1)
transcription factor, nuclear receptor: testicular development
development of genital ridge into biopotential gonad
mutation: 46, XY sex reversal or ambiguous genitalia
disease: gonadal and adrenal dysgenesis
Wilms tumor 1 (WT1)
transcription factor: testicular development
development of genital ridge into biopotential gonad; also important for KIDNEY
mutation: 46, XY sex reversal or ambiguous genitalia
disease: Frasier syndrome, Denys-Drash syndrome with Wilms tumor
LIM1
gene
gonadal development
EMX2
gene
gonadal development
SRY
Y chromosome
transcription factor: required for differentiation of gonad into testis (absent: gonad becomes ovary)
mutation: gonadal dysgenesis
SOX9
transcription factor: testicular development
mutation: campomelic dysplasia, male gonadal dysgenesis or XY sex reveral
RSPO1
development of ovary
WNT4
development of ovary
DAX1
transcriptional regulator, nuclear protein receptor: inhibits gonad from becoming a testis
mutation: gonadal dysgenesis, congenital adrenal hypoplasia
AMH/MIS
protein: causes regression of fetal mullein duct, Leydig cell inhibitor
mutation: persistent mullerian duct syndrome
StAR
steroidogenic acute regulatory protein: cholesterol into mitochondria
mutant: congenital lipoid adrenal hyperplasia
DHH
pro testis
AR
androgen receptor transcription factor
mutant: male pseudohermaphrodism, complete or partial androgen insensitivity syndrome
AMH/MIS type II receptor
kinase receptor
mutant: persistent mullerian duct syndrome
HSD17B3
17B-hydroxysteroid dehydrogenase, 17-ketosteroid reductase
mutant: male pseudohermaphroditism
SRD5A2
5a-reductase typer 2
mutant: male pseudohermaphroditism
virilization may occur at puberty
CYP17
17-hydroxylase; 20-22-lyase mutant: male pseudohermaphroditism low: cortisol increased deoxycortisone Sx: HTN, hypokalemia
CYP21
21-hydroxylase
mutant: congenital adrenal hyperplasia, female pseudohermaphroditism
HSD3B2
3B-hydroxysteroid dehydrogenase type II
mutant: congenital adrenal hyperplasia
can cause 46, XX or 46, XY DSD
CYP11B1
11B-hydroxylase
mutant: congenital adrenal hyperplasia
FOXL2
development of ovary
Leydig cell
secrete: testosterone
Sertoli cell
secrete: AMH
urogenital sinus
male: prostate gland
genital tubercle
male: glans penis
female: clitoris
labiourethral folds
male: urethra, ventral shaft of penis
female: labia minora
labiosacral folds
male: scrotum
female: labia majora
congenital adrenal hyperplasia
MOST COMMON cause of ambiguous genitalia
AR
46, XX DSD
potentially FERTILE
most common defect: 21-hydroxylase deficiency (CYP21); 11-B-hydroxylase deficiency (CYP11B1), 3B-hydroxysteroid dehydrogenase deficiency (HSD3B2 and also a cause of 46, XY DSD)
elevated: 17-hydroxyprogesterone, DHEA, androstenedione, ACTH, PRA (indicates aldosterone deficiency)
low: cortisol
Sx: HTN, areolar hyperpigmentation, dehydration, hyponatremia, hyperkalemia, metabolic acidosis
classic: newborn, salt wasting
Tx: glucocorticoids, fludrocortisone
testosterone biosynthetic defects
AR
46, XY DSD
HCG stimulation: low testosterone and DHT
Leydig cell hypoplasia
AR
46, XY DSD
HCG stimulation: low testosterone and DHT
5a-reductase deficiency
AR
46, XY DSD
mutation: SRD5A2
elevated: testoterone/DHT ratio (after HCG stimulation)
puberty: virilization occurs in many
skin fibroblast culture for 5a-reductase deficiency
androgen insensitive syndrome
X linked 46, XY DSD mutation: AR elevated: AMH normal: testosterone levels with normal rise with HCG stimulation risk: gonadoblastoma
gonadal dysgenesis (Swyer syndrome)
sporadic and familial sex chromosome DSD mutation: SRY (most it is intact) elevated: gonadotropins low: AMH HCG stimulation: low testosterone and DHT risk: germ cell tumor complete: phenotypic females (not ambiguous) Sx: amenorrhea at puberty
ovotesticular DSD
- internal genitalia
- external genitalia
- fertility
- gender assignment
sporadic and familial
most: 46, XX; also sex chromosome DSD
1. both testicular and ovarian tissue, most uterus
2. usually ambiguous; can have normal male or female
3. ?
4. depends on external/internal genitalia (many develop gynecomastia and menstruate)
risk: gonadoblastoma
What should the penile length be of a full-term newborn?
greater than 2.5 cm
anogenital ratio
AF/AC
AF: distance from the anus to the fourchette
AC: distance from the anus to the base of the clitoris
anogenital ratio greater than 0.5: fusion of labioscrotal folds (virilization)
normal full term phallus: 2.5 cm
sex chromosome DSD
- internal genitalia
- external genitalia
- fertility
- gender assignment
karyotype is not typical 46, XX or 46, XY
- one dysgenic testis, one streak gonad, no ovarian tissue
- ambiguous
- ?
- MGD: most female
mixed gonadal dysgenesis (partial gonadal dysgenesis)
45,X/46,XY
sex chromosome DSD
ambiguous asymmetrical external genitalia: enlarged labioscrotal fold on side with testis
risk: germ cell tumor
chimerism
46,XX/46,XY
sex chromosome DSD
Turner syndrome
45,X
sex chromosome DSD with un-ambigious genitalia
Klinefelter syndrome
47,XXY
sex chromosome DSD with un-ambigious genitalia
aromatase deficiency
46, XX DSD
disorders of androgen synthesis or action
- internal genitalia
- external genitalia
- fertility
- gender assignment
46, XY DSD 1. testes in abdomen 2. female 3. ? 4. ? mutations: StAR, CYP11A low: testosterone elevated: LH HCG stimulation: no rise in testosterone
congenital lipoid adrenal hyperplasia
46, XY DSD
mutation: StAR, CYP11A
no steroid hormones are made, severe salt wasting
often fatal
CYP11A
cholesterol side chain cleavage enzyme
mutation: congenital lipoid adrenal hyperplasia
3B-hydroxysteroid dehydrogenase deficiency
46, XY DSD mutation: HSD3B2 low: cortisol increased deoxycortisone Sx: HTN, hypokalemia
17B-hydroxysteroid dehydrogenase or 17-ketosteroid reductase deficiency
46, XY DSD
mutation: HSD17B3
NO signs of CAH
HCG stimulation: low testosterone, DHT
persistent mullerian duct syndrome
46, XY
NO ambiguous genitalia
mutation: AMH or AMHRII
Sx: cryptorchidism, hernia uteri inguinale
few are fertile, high incidence of postnatal testicular degeneration
congential anorchia
testes function at least until 16 week of gestation then disappeared
elevated: LH, FSH
low: testosterone, AMH
Tx: testosterone therapy at puberty
Denys Drash syndrome
WT1 mutation
nephropathy, wilms tumor, genital abnormalities
Frasier syndrome
WT1 mutation
normal external female genitalia with XY karyotype
streak gonads that often develop into gonadoblastoma
nephrotic syndrome
Smith-Lemli Optiz
mutaiton in 7-dehydrocholesterol reductase leading to increase in 7-dehydrocycholesteol
look female
XY: undervirilized