Amongst children undergoing routine UPJ repair, the incidence of postoperative febrile UTI in our cohort is relatively low (5%), consistent with current reported rates of 1–3% [4]. When evaluating potential risk factors for development of febrile UTI in the initial 30-day postoperative period, we did not identify an association between the use of perioperative Abx, surgical approach, or urinary drainage method. However, younger age and the presence of a positive culture within the month to surgery did correlate with a higher rate of postoperative febrile UTI. Furthermore, additional analysis indicate that insurance status might also impact the presentation of UTIs. Similar results were seen in Ferroni et al., where postoperative antibiotics did not alter the rate of UTIs in patients undergoing minimally-invasive UPJ repair [5]. Our study population included various surgical techniques, generalizable to the overall pediatric surgery population. While our study indicates that antibiotic Abx is not effective in reducing post-pyeloplasty UTIs in majority of our patients, there is a selective group of young children who might benefit from prophylactic Abx. Our analysis indicates that children younger than 3 years old have a higher risk of postoperative febrile UTIs. This might be related to toilet-training, similar to the population included in the recent AAP UTI guideline [3].
While there has been concern for potential infection risk associated with ureteral stent usage due to high colonization rates [6], the risk of infection is low when they are maintained for less than 90 days [7]. Since our post-pyeloplasty stents remain in place for at most 4–6 weeks, it makes sense that we did not find any association between use of a ureteral stent and postoperative febrile UTI. We also used patient insurance type, Medicaid versus non-Medicaid, as a surrogate for potential socioeconomic status. In our cohort, patients with Medicaid did not show a higher risk of febrile UTI postoperatively. However, they were more likely to have a febrile event postoperatively when we include febrile UTIs and fever with positive urinalysis. Our study was not powered to study this difference; moving forward, future study would be needed to if there to assess is a social factor as potential barrier to care access. In our study population, the results of a positive urine cultures within 30 days of surgery did significantly correlate with incidence of symptomatic UTI. Perhaps this is a cohort of patients who should be maintained on postoperative antibiotics, and these patients should be selectively treated with antibiotics to prevent a febrile UTI. There is another patient population that are at risk for postoperative UTIs. Studies have shown that febrile UTI’s represent the most common type of complication in young patients diagnosed with bronchiolitis patients and are particularly common in infants with bronchiolitis (positive RSV culture with symptoms) [7–10]. The current AAP guidelines on bronchiolitis recommend treating only patients with symptoms for concurrent UTI and bronchiolitis [11]. Based on these studies, we suggest a preoperative culture within 30 days of surgery for patients under 2 years of age with a history of bronchiolitis. A urine culture is particularly high yield for this cohort and could help determine whether to treat with prophylactic Abx. A complicating factor in our analysis of the effect of antibiotic prophylaxis is the high rate of Abx treatment for “UTI’s” without use of urinalysis or urine culture. A 2013 analysis by Copp et al. estimated that, of all patients treated with antibiotics for UTI, 76% receive a urinalysis and only 57% receive urine culture [12]. This rapid treatment paradigm likely comes from the desire to limit renal scarring. As the study by Shaikh, et al. shows, a delay in antibiotic treatment greater than 48 hours is associated with significant risk for renal scarring in children younger than 6 years of age [13]. This risk encourages physicians to quickly respond to suspected febrile UTI’s, but we believe there is an opportunity for more judicious prophylactic Abx use. To more closely consider the effect of this treatment paradigm, we included patients who presented with a fever and positive urinalysis within 30 days of surgery in our analysis. These patients often received antibiotics. However, the addition of prophylactic Abx did not affect the rate of febrile urinary events of either type. While our study did show a limited potential for Abx use in patients undergoing UPJ, our study was limited by its retrospective nature in a single institution. Furthermore, most patients had ureteral stents and robotic surgery, which makes comparison of the different urinary drainage options and surgical approaches limited by numbers. Since we were only able to gather data available during our patient encounters, it is possible that patients were seen at outside facilities for febrile UTIs with no records of urinalysis or culture results, and these events were missed in our analysis. Lastly, most of the urine cultures obtained for patients undergoing pyeloplasty were done intraoperatively at the time of surgery, and therefore these patients could not be treated prior to surgery based on results. This is mainly limited by patient convenience to present for a separate appointment prior to surgery to obtain a urine culture. Based on our current model, the intraoperative urine culture results can be used to guide use of antibiotics postoperatively on day of discharge, usually the day after surgery. Finally, due to the overall low number of events of febrile UTIs after pyeloplasty, larger groups are needed to better define an algorithm guiding prophylactic antibiotic use in higher risk patients.
