Effects of early vesicostomy in obstructive uropathy on bladder development.
OBJECTIVE
Creation of a vesico-amniotic shunt for obstructive uropathy removes the normal fetal urination cycle. It is unclear how this affects bladder function at term. The authors measured the bladder volume and reviewed the bladder histology after fetal vesicostomy.


METHODS
The authors created an obstructive uropathy in fetal lambs at 60 days' gestation by ligating the urethra and urachus. Vesicostomy (female) or urethrostomy (male) were performed 21 days after obstruction to release the obstruction. The fetuses were killed at term (145 days).


RESULTS
Thirteen fetuses were shunted. Seven fetuses miscarried after shunting. Six survived, and 3 had a successful shunt with a very small bladder (5 to 7 mL). Two had incomplete shunts that failed some time after shunting. These both had huge bladders (399 mL). In one, the obstruction was unsuccessful. Histologic examination showed that the obstruction caused bladder muscle hypertrophy. Shunted lambs had severe fibrosis of the bladder wall and very poor bladder compliance.


CONCLUSIONS
Shunt operations after obstructive uropathy may salvage the kidney but fail to preserve bladder function. The fetus needs a normal urination cycle for normal bladder development. This requirement exists even when the obstruction is successfully bypassed.
Sato
Yuriko
Y
Division of Pediatric Surgery, St Marianna University School of Medicine, Kawasaki, Japan.
Kitagawa
Hiroaki
H
Pringle
Kevin C
KC
Koike
Junki
J
Zuccollo
Jane
J
Robinson
Richard
R
Wakisaka
Munechika
M
Seki
Yasuji
Y
Nakada
Koonosuke
K
D000367:Age Factors; D000818:Animals; D003559:Cystostomy; D004195:Disease Models, Animal; D012756:Sheep; D014524:Urethral Obstruction / Q000150:complications*; D001743:Urinary Bladder / Q000196:embryology* / Q000473:pathology