Treatment outcome and predictors of poor clinical response in extensively drug-resistant gram-negative urinary tract infection among children: A single-institution experience

Introduction: Extensively drug-resistant (XDR) is defined as isolates sensitive only to two or fewer antimicrobial categories. This paper aims to present the treatment outcome and identify factors associated with poor clinical response among children with XDR gram-negative urinary tract infection (UTI). Methods: This is a retrospective cohort conducted at a tertiary pediatric hospital from January 2014 to June 2017. All patients diagnosed with culture-proven XDR gram-negative UTI were identified and analyzed. Descriptive statistics were used to summarize demographic and clinical characteristics. Patients were categorized according to treatment outcomes: success vs. failure. Univariate analysis and multivariate logistic regression were used to assess statistical differences between the groups and determined patient variables that are predictive of poor response. Odds ratio (OR) and corresponding 95% confidence interval (CI) were generated. Results: A total of 29 (19.2%) XDR gram-negative pediatric UTI's were identified within the 42-month study period. No significant differences were noted in demographic characteristics between the groups. Treatment outcome of XDR gram-negative UTI patients showed that combination therapy with colistin had the highest success rate (40.9%), followed by non-colistin (36.4%) and combination therapy without colistin (22.7%). However, univariate analysis showed no significant difference among the different treatment groups (p=0.65). On multivariate logistic regression, receiving immunosuppressant and the presence of indwelling urinary catheters were independent predictors of poor clinical response among pediatric patients with XDR gram-negative UTI (OR 19.44, 95% CI 1.50-251.4, p=0.023 and OR 20.78, 95% CI 1.16-371.28, p=0.039; respectively). Conclusions: The treatment success rate of XDR gram-negative pediatric UTI ranged from 22.7-36.4%. This finding emphasizes the need to advocate antibiotic stewardship to prevent further increase in XDR UTIs. Indwelling urinary catheters and receipt of immunosuppressants are associated with poor clinical outcome.