Duplex

Question 1

what is embryology of duplex kidney

Answer 1

metanephros is kidney
ureteric bud from lower mesonephric duct grows cranially
meet the metanephros at 32 days
by recipricol induction, they generate a kidney
urine production begins at 10 weeks
if extra ureteric bud generated will head to the metanephros and develop into second ureter
ureteric bud that meets more cranial metanephros will generate the upper moeity ureter
which will be from more caudal mesonephric duct resulting in more caudal position when mesonephric duct subsumed into bladder
meyer weigert rule upper moeity ureter inserting lower and more medially

Question 2

incidence duplex

Answer 2

1:125

Question 3

complications associated duplex

Answer 3

obstruction upper moeity and non function
lower moeity reflux
ureterocele of upper moeity
upper moeity ectopic
the more ectopic the ureter the more dysplastic the kidney and more difficult to find

Question 4

bilateral incidence

Answer 4

40%

Question 5

incidence complete duplication

Answer 5

0.1%

Question 6

ureteric bud where form

Answer 6

caudal accessory ureteric bud
will insert superolaterally and connect lower pole moeity
has a shorter intramural length more likely reflux
or refluxes due to distortion of abnormal insertion other ureter

cranial accessory ureteric bud
UO inferomedial position
often with ureterocele
connects upper pole associated obstruction

Question 7

incision of ureterocele

Answer 7

as close to bladder neck as possible

Question 8

risk of heminephrectomy

other alternatives to

Answer 8

Treatment of choice upper pole moiety heminephrectomy via laparoscopy and child will be dry afterwards
down side of heminephrectomy is risk of loss of function of lower normal moiety at rate of 5-10%
Can do lap ligation of upper pole ureter with ureteric catheter in correct ureter beforehand
Ureteroureterostomy at lower end