Time-related changes of metabolic and physicochemical profiles in patients with mechanical ileal neobladders
Martino Marangella1, Andrea Formiconi, Michele Petrarulo
1Nephrology Unit and Renal Stone Centre, Mauriziano Hospital, Turin, Italy.
Objective:
To investigate metabolic disturbances, possibly leading to stone disease, in the Camey II technique for creating a urinary reservoir from an intestinal segment.
Patients, Subjects And Methods:
Thirty patients with a Camey II ileal neobladder and 26 controls had metabolic investigations of blood samples, and 24-h and fasting urine samples, to assess renal function, the risk of stone formation, and bone turnover. The state of saturation with calcium oxalate, uric acid and brushite were calculated using a computer program.
Results:
The patients had lower renal clearances than the controls (P < 0.001), with a slight tendency to decrease with time from surgery. Metabolic hyperchloraemic acidosis occurred in 57% of the patients and tended to be worse at lower glomerular filtration rates (P < 0.05). Severe hypocitraturia in both daily and fasting urine was the most striking urinary feature. There was no difference in the other variables. The state of saturation with brushite was slightly higher in patients due to the slightly higher urinary pH. There was a trend to lower bone turnover, involving markers of both resorption and formation, in the patients.
Conclusions:
The Camey II technique led to only minor functional or metabolic changes; renal function tended to deteriorate and mild metabolic acidosis was the main feature. Fasting and 24-h hypocitraturia occurred in most patients, representing a potential threat for calcium stone formation.
