197/198/199 - UG Development, Congenital Anomalies, Sexual Differentiation Flashcards Preview

Repro/GU by Minnie (she/her) > 197/198/199 - UG Development, Congenital Anomalies, Sexual Differentiation > Flashcards

Flashcards in 197/198/199 - UG Development, Congenital Anomalies, Sexual Differentiation Deck (58)
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C - congenital adrenal hyperplasia due to 21-alpha-hydroxylase deficiency


  • Testicular DSD will have male external genitalia
  • In partial androgen insensitivity syndrome, gonads are present; will not have XX karyotype



Describe the presentation of posterior urethral valves

  • Prenatal
    • Bilateral hydronephrosis
    • Thick-walled bladder
    • Oligohydraminos
  • Post-natal
    • UTI
    • Renal insufficiency
    • Pulmonary insufficiency
    • Incontinence
    • Poor urinary stream




What is the role of sertoli cells in sexual differentiation?

Produce AMH -> regression of mullerian ducts


E - posterior urethral valves


Which primordial tissue gives rise to the kidney nephrons?

Metanephric mesoderm


Which indifferent-stage structure gives rise to the prostate and prostatic urethra in 46, XY individuals?

What is the corresponding structure in 46, XX individuals?

Urogenital sinus


Lower vagina and urethra in 46, XX individuals


Why is testosterone elevated in 21-alpha-hydroxylase deficiency?

Normally, 21-alpha-hydroxylase turns 17-OH-progesterone into 11-deoxycortisone


Without 21-alpha-hydroxylase, 17-OH-progesterone is shunted towards the testosteone synthesis pathway -> increaesed testosterone


In females, the secondary sex cords will give rise to which adult structure?

What kind of cells is this structure composed of?

Ovarian follicles

Ovum surrounded by epithelium of granulosa cells


Note: Primary sex cords persist as nonfunctional/vestigial rete ovarii


What is the most common congenital cystic kidney disease?

Multicystic dysplastic kidney


Where in the male is junction of the urethra derived from the urogenital sinus and surface ectoderm?


A. Urinary bladder and prostatic urethra

B. Beginning of the penile urethra

C. Proximal and distal halves of the penile urethra

D. Penile urethra and navicular fossa in the glans

E. Penile urethra and distal epidermis of the glans

D. Penile urethra and navicular fossa in the glans


Where in the adult female is the junction of derivatives of the paramesonephric ducts and urogenital sinus?


A. Uterine tubes and uterus

B. Uterine fundus and cervix

C. Uterus and vagina

D. Middle of the vagina

E. Vagina and vestibule

D. Middle of the vagina


Describe the internal and external genitalia that result from complete androgen insensitivity syndrome in a 46, XY individual

Testosterone present, but receptors non-functional

  • Internal
    • Testes, often undescended
    • AMH secreted -> no uterus or Mullerian structures
  • External
    • No testosterone action -> female external genitalia
    • Testosterone aromatized to estrogen -> breast development


Often presents in a female-presenting individual with primary amenorrhea 

5-alpha-reductase deficiency will have female external genitalia but then development of male structures in puberty 2/2 increased testosterone


In a ureteral duplication:

  • Which ureter is more likely to develop obstruction?
  • Which is more likely to develop reflux?

  • Obstruction: Ureter from upper moiety
    • Inserts inferiorly and medially in the bladder
    • Also more likely to have ectopic ureter, ureterocele 
  • Reflux: Ureter from lower moiety
    • Inserts laterally and superiorly in the bladder
    • In general, this is more anatomically normal



Which 2 embryonic primordia form the male urethra?

  • Urogenital sinus (endoderm) -> proximal majority
  • Navicular fossa (ectoderm) -> distal end


Failure of fustion = hypospadias; opening on the ventral surface


A woman is infertile because of an absence of ova.  Where might primordial ova have failed to differentiate?


A. Genital ridge mesoderm

B. Primary sex cords

C. Hindgut endoderm

D. Secondary sex cords

E. Paramesonephric duct

C. Hindgut endoderm


Primordial germ cells orginate in the hindgut, then migrate to the genital ridge

Sex cords give rise to the epithelial components of the gonads only


What is most common cause of ureteropelvic junction obstruction that is...

  • Intrinsic:
  • Extrinsic:

  • Intrinsic: Aperistaltic segment
    • Most common overall cause of UPJ
  • Extrinsic: Crossing vessels



Which cells produce anti-mullerian hormone?

Sertoli cells


No gonads/streak gonad -> no Sertoli cells or Leydig cells -> no AMH or testosterone (respectively) -> Mullerian structures persist, no androgen effect on external genitalia 


Fetal hydronephrosis 2/2 urinary tract dilation is detected on prenatal ultrasound 

How should this be managed?


50-80% of antenatal hydronephrosis will spontaneously resolve; does not necessarily represent a specific pathology


What are the adult derivatives of the labioscrotal folds in...

  • Males:
  • Females:

  • Males: Scrotum
  • Females: Labia majora



C - complete androgen insensitivity syndrome


  • 5-alpha reductase = no breast development 
  • Mixed gonadal dysgenesis is similar, but will not have symmetric inguinal masses (testes)
  • 21-hydroxylase deficiency would present much earlier
    • Salt wasting, hyperkalemia, failure to thrive soon after birth 


Describe the internal and external genitalia that result from 5-alpha-reductase deficiency in a 46, XY individual

  • Internal
    • Testes, synthesize AMH -> no mullerian structures
    • Also synthesize testosterone
  • External
    • Cannot convert testosterone to DHT -> Variable external genitalia
    • Depends on amount of DHT that is produced
    • More DHT -> more development of male structures


Male structures will often begin to develop during puberty due to increased testosterone


Where are sperm synthesized?

Where are they stored?

Synthesis: Testes

Storage: Epididymis


What embryonic structure gives rise to the ureter?

Mesonephric duct -> Ureteric bud


Keys is that the ureteric bud comes from the mesonephric duct, not the urogenital sinus


What causes mixed gonadal dysgenesis?


One side has streak gonad, other has dysgenetic testicle


Most likely dx if testes are asymmetric


Which one of the following could persist as a cystic structure in the middle of the broad ligament of the uterus?

A. Urogenital sinus

B. Mesonephric duct

C. Allantois

D. Paramesonephric duct

E. Metanephric duct

B. Mesonephric duct


Remnant of the mesonephric duct - should only persist in male development


Which side is more susceptibel to ureteropelvic junction obstruction?


(and M > F)


List the steps in the pathway that sperm take from the testes to the outside world

  • Testes (synthesis)
  • Epididymis (storage until ejaculation)
  • Vas deferens (aka ductus deferens
  • Inguinal canal
  • Seminal vesicles (picks up semen here)
  • Ejaculatory duct (after joining the prostatic urethra)
  • Membranous urethra
  • Penile urethra
  • Outside world



Extrophy of the bladder results from failure of mesoderm migration into which fetal structures?

Cloacal membrane/ventral abdominal wall


What is the most common etiology of ureteropelvic junction obstruction that presents with intermittent flank pain?

Crossing vessel


Adynamic segment, high insertion, intrinsic narrowing would either be asymptomatic or constant


What is the fate of the primordial mesonephric duct? (4)

Male internal structures

  • Seminal vesicles
  • Epididymis
  • Ejaculatory duct
  • Ductus deferens (aka vas deferens)



Note: Ureteric bud (-> ureters, pelvis, calyces, collecting duct) comes from the mesonephric duct