Independent validation of a predictive nomogram for risk of reinfection in women with recurrent non-complicated urinary tract infections.

Aims: Independent external validation of a predictive nomogram for risk of reinfection in women with a history of non-complicated recurrent urinary tract infection (UTI).

Methods: A retrospective longitudinal study was conducted to validate the LUTIRE nomogram in a Brazilian female cohort. The nomogram was applied to 81 women presenting non-complicated recurring UTI screened at a urological clinic. External validation was performed using the nomogram variables in patients followed up from January 2014 to December 2016 at a urological clinic. Accuracy of the nomogram was obtained by analyzing the predictive capacity observed in the area under the receiver operating characteristic (ROC) curve. A multivariate logistic regression model was used to assess the ability of the nomogram variables to predict the recurrence of UTI over 12 months. The time to recurrence of infection was calculated using a Kaplan-Meier curve and the log-rank test with calculation of the hazard ratio.

Results: The mean age of the study population was 42.8 years; 57 women (70.37%) had recurrence. The independent variables with statistical significance in the multivariate analysis were gram-negative bacteria [odds ratio (OR) 18.38;  = 0.03897] and number of UTIs in the past 12 months (OR 25.11;  = 0.00006). The accuracy of the nomogram for discriminating patients who had UTI recurrence was 82.6% (95% CI = 72.5-90.1).

Conclusion: The LUTIRE nomogram showed good accuracy among Brazilian women with recurrent UTI.