Pediatrics

Question 1

What does cranial urogenital sinus become

Answer 1

bladder and pelvic urethra, continous with allantois

Question 2

what does Caudal urogenital sinus become

Answer 2

phalic urethra and distal vagina

Question 3

What does allantois become

Answer 3

Urachus and medial umblical ligament

Question 4

What is the detection rate of bladder prenatally on US?

Answer 4

depends on time
50% at 10 weeks- concurrent with start of urine production
78% 11 weeks
88% 12 weeks
100% 13 weeks
Bladder empties Q 15-20 mins. So if u cant see it try again. Maybe its empty. In 1st trimested will be 6-8 mm.

Question 5

classify prenatally detected bladder anomolies

Answer 5

Dialated with obtruction( congenital urethral strictures, ant and post urethral valves, Urethral atresia, obstructing syringocele, sarcococcygeal teratoma, sacral myelomeniogecle, rectum anomlies
no obstruction: Prunne belly syndrome, neurogenic bladder, congenital megacystitis
Nondialated: clocal and bladder exstrophy, bladder hypoplasia, bladder agensis

Question 6

classify post-natally detected bladder abnormalities

Answer 6

Urachal ( patent urachus, umblical urachus sinus, urachal cyst, vesicourachal diverticulum

Question 7

What are the different types of bladder diverticulum detected post-natally?

Answer 7

Priamry paraureteral (congenital) , secondary paraureteral( often bc of obstruciton, weakening of bladder wall by sx or infection ) 
Iatrogenic, caused by infravesical obstruction or congenital defect

Question 8

what is the gold standard for dx of bladder diverticula in peds?

Answer 8

VCUG

Question 9

what are the different types of bladder duplication and what anomolies are they associated with

Answer 9

Complete or incomplete.
coronal or saggital. associated with abnormalities of external genitalia and lower GI tract. Saggital duplication is most common

Question 10

what is the tx of nephrogenic adenoma in peds?

Answer 10

TUR + ibuporfen and TMP SMX

Question 11

What is the treatment of eosinophilic cystitis in peds?

Answer 11

TUR = Bx of lesion then CS, Antihistamines, =/- abx. observation in very young neonates can be done

Question 12

What 3 steps must occur for normal sexual differentiation?

Answer 12

1- Chromosomal sex at fertilization
2- Gonadal differentiation
3- differentiation of internal duct and ext genitalia

Question 13

What gene is the Testis determining factor? complete name?

Answer 13

SRY( sex-determining region Y- gene)

Question 14

Where is the SRY gene located?

Answer 14

distal portion of the short arm of The Y chromosome

Question 15

name a gene that is involved in sexual determination and is associated with aniridia?

Answer 15

WT1-

associated with WAGR(wilms tumor, aniridia, Genitourinary findings and retardation)

Question 16

Upto what age is the embryo bipotential sex determination?

Answer 16

6 weeks

Question 17

Describe the journey of the primordial germ cells 3-5 weeks gestation?

Answer 17

at 3 weeks they develop and migrate along the wall of the yolk sac to the fetus, reaching their destination at 5 weeks at the gonadal ridge

Question 18

what causes the indifferent gonad to become a testicle?

Answer 18

SRY gene

Question 19

What is the first endocrine product formed by the testis? function?

Answer 19

MIS(mullerian inhibiting substance)/ AKA anti-mullerian hormone at 7-8 weeks, causes regression of ipsilateral mullerian structures

Question 20

What is required for ovarian organogenesis

Answer 20

abscence of SRY gene

duplicate copies of at least one, yet unidentified x chromosomal locus

Question 21

fetal ovaries undergo intense (……) proliferation to reach 20 million cells by (…) weeks GA.

Answer 21

Mitosis, GA

Question 22

What cells formed in the testis at 9 weeks GA produce testosterone?

Answer 22

leydig cells

Question 23

What promotes the production of testosterone in utero?

Answer 23

1- initially, autologus
2- placental hcg
3- LH from pituitary

Question 24

what are 3 functions of testosterone in embryo?

Answer 24

1- virilization of wolfian structures( local/adjacent effect)
2- virilization of urogenital sinus (systemic)
3- virilization of genital tubercle (systemic)

Question 25

What is the role of DHT in sexual development?

Answer 25

external virillization
sexual maturation at puberty
converted from testosterone in the urogential sinus , prostate and external genitalia by 5-AR

Question 26

what effect does estrogen have on female differentiation of internal or external genitalia

Answer 26

none

Question 27

how does the presence of estrogen effect the development of male genitalia?

Answer 27

Blocks MIS and associated with male reproductive tract abnormalities

Question 28

Internal genital analogues for male and female
Indifferent stage, male, female
gonad
mullerian duct
wolfian duct
mesonephrons

Answer 28

Indifferent stage, male, female
gonad M-testis, F- ovary
mullerian duct F- fallopian tube, uterus, upper 2/3 vagina
wolfian duct M-vas deferens, seminal vesicle
mesonephrons M- epididymis

Question 29

what causes wolfian duct to involute?

Answer 29

absense of testosterone

Question 30

When do penile formation, elongation and testicular decent occur?

Answer 30

formation : starts at 10 weeks, complete at 13
elongation 3rd trimester
testicular decent: 3rd trimester