[Experimental microsurgical gastrocystoplasty]

Stomach tract used for bladder augmentation decreases urinary pH and produces the syndrome of dysuria and hematuria; gastric mucosa in contact with urine may develop prominent histopathological changes including proliferative lesions. The aim of this study was to investigate in an experimental model the possibility of detecting the factors involved in the mucosal damage.

Thirty-five Sprague Dawley rats randomly underwent microsurgical gastrocystoplasty or sham operation (5 controls). During operation elliptical gastric patch was isolated with its gastroepiploic vascular pedicle, bladder was opened with midline incision and anastomosis performed. Urine was aspirated from the bladder for culture, pH and electrolytes evaluation; venous blood was samples for electrolytes, BUN and creatinine. Mean follow-up time was 6 months.

Of the 30 rats subjected to gastrocystoplasty 23 survived (77%). All of cultures were negative, the urinary pH decreased after operation and increased gradually two months later. Urinary sodium and potassium ions concentrations increased significantly in gastrocystoplasty (p < 0.05). There were no significant changes in serum electrolytes or renal function.

This experimental model was useful to investigate the effects related to the presence of gastric mucosa in the urinary tract.