Vesicoamniotic shunt for complete urinary tract obstruction is partially effective.
OBJECTIVE
The long-term outcome for children after antenatal intervention for obstructive uropathies is disappointing. We reported that renal dysplastic changes are well established 3 weeks after obstruction in a fetal lamb model. We used this model to explore renal development and bladder function after fetal intervention.


METHODS
We created an obstructive uropathy in fetal lambs at 60 days gestation by ligating the urethra and urachus. A vesicostomy (female) or urethrostomy (male) were performed 21 days later. The fetuses were killed at term (145 days) and bladder volume and compliance were measured. The urinary tract was processed for histologic examination.


RESULTS
Twenty two fetuses were shunted. Nine were miscarried or were still-born. Thirteen survived, and 11 had a successful shunt with a small bladder (8 +/- 5 mL) compared with controls (71 +/- 19 mL) (P < .05). Shunted bladders had poor compliance. Histologically, they had thickened submucosal connective tissue with hypertrophied muscle. Histology of the renal tissue demonstrated relatively well-preserved renal architecture with reduced nephron mass (oligonephronia) in 2 lambs and multicystic dysplastic change in 3. Six (55%) had normal nephrogenesis.


CONCLUSIONS
In our model, shunt operations after obstructive uropathy fail to preserve bladder function. Shunting ameliorated the development of cystic dysplasia, but half of the lambs had oligonephronia or multicystic dysplastic kidney. These might develop renal failure later in life.
Division of Pediatric Surgery, St. Marianna University School of Medicine, Kawasaki 216-8511, Japan. h2kita@marianna-u.ac.jp
Hiroaki
H
Kitagawa
Kevin C
KC
Pringle
Junki
J
Koike
Jane
J
Zuccollo
Yasuji
Y
Seki
Munechika
M
Wakisaka
Yuriko
Y
Sato
Hideaki
H
Sato
Hideki
H
Nagae
Koonosuke
K
Nakada
D000650:Amnion / Q000601:surgery*; D000714:Anastomosis, Surgical; D000818:Animals; D005315:Fetal Diseases / Q000601:surgery*; D005333:Fetus / Q000601:surgery*; D012756:Sheep; D014524:Urethral Obstruction / Q000473:pathology / Q000601:surgery*; D001743:Urinary Bladder / Q000601:surgery*