Factors causing variation in urinary N-nitrosamine levels in enterocystoplasties

Objective To establish the presence or absence of any diurnal or long-term variation in N-nitrosamine levels (which might be important in the development of cancer in enterocystoplasties) in enterocystoplasty urine, and to assess other factors that might alter enterocystoplasty N-nitrosamine levels. Patients, subjects and methods Thirty-six patients with enterocystoplasties and six normal controls were assessed. Urine samples were collected every 4 h over a 24-h period and N-nitrosamine levels determined using a modification of the Pignatelli method. An additional urine sample was assessed by microscopy, culture and sensitivity. In a subgroup of 16 patients with an enterocystoplasty, the urinary N-nitrosamine levels were re-measured at 3-monthly intervals. Results No diurnal or long-term variation in urinary N-nitrosamine levels was identified. The mean N-nitrosamine levels were significantly higher in the cystoplasty group than in the controls (1.7 vs 1.0 mu mol/L; P=0.008). Mean N-nitrosamine levels were also significantly higher in enterocystoplasty patients with sterile pyuria than in those with no pyuria (P=0.01). Those taking prophylactic antibiotics had significantly lower mean N-nitrosamine levels than those not doing so (P=0.05). Individuals with infected urine and those needing to intermittently catheterize had higher N-nitrosamine levels than their counterparts, but this difference was not significant. Conclusion There were no diurnal or long-term variations in urinary N-nitrosamine levels. Levels were consistently higher in patients with inflamed or infected cystoplasties, those using intermittent self-catheterization and those not taking antibiotic prophylaxis.