Urinary changes in patients following restorative proctocolectomy

Following restorative proctocolectomy, the physiological function of the large intestine to absorb water and electrolytes is lost. Therefore, the kidney plays an important role in adjusting the water and electrolyte balance along with the ileal pouch. The reservoir function of the ileal pouch, however, may affect the functional adaptation of urinary changes. To observe the functional adaptation of urinary changes in ileal pouch patients, their changes in urinary output and electrolytes were investigated. Urinary output, pH, and electrolytes were all measured at 1 month, 6 months, and 1 year after surgery in patients with a J-pouch (n = 30) and compared with those in patients who had undergone ileostomy (n = 11) and healthy controls (n = 22). In the patients with a J-pouch, the urinary output, pH, and sodium concentration were significantly lower than those of the controls at 1 month after the operation. However, they gradually increased to near the control values at 1 year. In patients with an ileostomy, the urinary output, pH, and sodium concentration were lower than the control values up to 1 year postoperatively, but the urinary uric acid concentration was higher than that in the controls in both groups up to 1 year. The patients who had persistent aciduria were given a citrate mixture (3g/day), which effectively normalized the aciduria and also possibly prevented urinary uric acid stone formation.