Splenic cyst presenting as severe hydronephrosis in a pediatric patient.

Large cystic abdominal masses can represent a diagnostic dilemma despite advanced diagnostic and imaging techniques. We report a case of a large cystic mass initially managed as a giant ureteropelvic junction obstruction, but ultimately found to be a congenital splenic cyst. Focus is placed on the diagnostic evaluation of large cystic abdominal masses.

Urethral polyp in asymptomatic male infant with prenatal hydronephrosis.

Congenital posterior urethral polyps are rare, benign lesions of the posterior urethra. We report a 1-day-old newborn boy with a solitary fibroepithelial posterior urethral polyp who presented with a history of prenatal mild hydronephrosis, subsequently associated with bladder wall thickening on ultrasonography.

Autoaugmentation gastrocystoplasty: further studies of the sheep model.

OBJECTIVE: To report our experience with autoaugmentation gastrocystoplasty (AAGC, reported to result in an inconsistent augmentation effect in children) in a sheep model, specifically addressing issues of surgical techniques and postoperative bladder drainage that may affect the augmentation result, as many factors have been implicated in the poor outcome. MATERIALS AND METHODS: Ten 6-month-old male lambs had a suprapubic catheter placed by an open laparotomy. Intraoperative urodynamics were evaluated before and after detrusorotomy for autoaugmentation and after completing AAGC. The bladder was drained with no distension for 1 week after surgery and the urodynamic evaluation repeated on control and experimental animals 6 months after surgery. The animals were then killed and the bladders evaluated for gastric flap survival and histological changes in the native bladder and augmentation segments. The results were analysed using a one-sided Student's t-test. RESULTS: The median (range) native bladder volume at leak-point pressure was 110 (40-490) mL. Intraoperative bladder volumes after completing AAGC confirmed adequate augmentation segments in all animals. The urodynamic evaluation at 6 months after AAGC showed increases in bladder volumes in nine of 10 animals (0-1336 mL), significantly greater than the increase in volume in the control sheep (median 337.5 vs 115.3 mL; P < 0.05). The bladder compliance (volume/pressure at leak capacity) 6 months after AAGC was slightly better but not significantly higher than in controls (median 17.3 vs 10.8 mL/cmH(2)O; P > 0.05). The median (range) ratio of surviving gastric flap to native bladder circumferences was 34.5 (31-53)%. Histology showed scarring of the submucosal layer in one of 10 augmentation segments and normal urothelium in all bladders. CONCLUSION: AAGC produces reliable bladder augmentation and excellent bladder compliance in a sheep model of a non-neurogenic bladder. The gastric flap survived well and there was no bladder wall separation with simple postoperative catheter drainage.

Flow cytometry analysis of proliferative lesions at the gastrocystoplasty anastomosis.

PURPOSE: Proliferative epithelial metaplasia that develops in the anastomotic line after gastrocystoplasty has unknown malignant potential. Flow cytometry analysis of cell cycle profiles is used to predict the neoplastic progression of metaplastic lesions in other proliferative epithelium. We used this technique to evaluate transitional cell metaplasia in rat gastrocystoplasty specimens. MATERIALS AND METHODS: A total of 50 prepubescent female Long-Evans rats were randomly assigned to an experimental group (gastrocystoplasty) or a control group (sham operation). At 21 to 27 months (mean 24.9) after operation 12 rats per group survived to sacrifice. Metaplastic lesions were microdissected to yield a minimum of 10(4) cells for DNA flow cytometry and cell cycle analysis. Transitional cell epithelium from sham specimens and gastric epithelium from experimental animals served as controls. RESULTS: Transitional cell hyperplasia and metaplasia with cyst formation were found in the anastomotic line in all 12 augmented bladders (100%). No proliferative lesions developed in control animals. No nuclear pleomorphism or mitotic changes were identified on routine histological examination. The epithelial cell turnover rate was 10 times higher in the gastrocystoplasty junctional zone than in control bladders (mean 2.2% versus 0.1% S phase) but lower than in native stomach epithelium (mean 3.3% S phase). Of 12 experimental specimens 1 showed near diploid DNA aneuploidy. No DNA abnormalities were detected in control bladder or stomach specimens. CONCLUSIONS: In this animal model histologically benign appearing proliferative lesions that develop in the anastomotic zone after long-term gastrocystoplasty harbor cell cycle and DNA ploidy abnormalities.