Abstracts from the New England Section of the AUA 2020: A Virtual Experience

NE AUA 2020 Abstracts Inpatient Urologic Consultation is not Necessary to Ensure Follow up in Patients with Uncomplicated Ureterolithiasis Meredith C. Wasserman, MD, MS , David W. Sobel, MD, Siddharth Marthi, BS, Edmond Godbout, PA, Chris Tucci, MS RN, Gyan Pareek, MD, MS Brown University, Providence, RI Introduction: The incidence of nephrolithiasis continues to increase and efficacious and safe emergency department management of acute renal colic is critical to patient outcomes. In 2016 we developed a novel Stone Observation Pathway (SOP) within our institution’s Clinical Decision Unit (CDU) for patients with acute renal colic to have up to 24 hours of observation in order to control pain and treat associated symptoms with the goal of a safe discharge on MET without requiring hospital admission or urologic consultation. We found the overall follow-up rate was 54% prompting further investigation into factors that may affect this. Materials & Methods: A retrospective review of all patients discharged from the CDU through the SOP for uncomplicated ureterolithiasis from January 2016 to November 2019 was conducted. Patient characteristics, axial imaging, and follow-up information were analyzed. Of note, it was assumed if a patient did not follow up with a urologist within our department, they did not followup. Patients known to followwith an outside urologist were excluded from analysis. Inpatient urologic consultation was not required during observation, however the on-call urologist was alerted to patients with acute kidney injury, severe hydronephrosis or calculi > 10 mm. It was to the urologist’s discretion if an inpatient consult was performed. Statistical analysis was performed using the chi-squared test. Results: 141 patients with uncomplicated ureterolithiasis discharged from the CDU without intervention were included in the analysis. The mean stone size for all patients discharged was 4.1 mm (SD +/- 1.9 mm). Table 1 summarizes results and data analysis. 76 patients discharged from the CDU followed upwith a urologist (54%). 28% of patients had a urologic consultationwhile under observation in the unit. Inpatient urologic consultation was not associated with follow-up rates (chi squared = 1.678, p < 0.05). Outpatient follow- up with a urologist was, however, associated with a prior stone history as well as prior care established with a urologist (chi squared = 0.0064, p < 0.05; chi squared = 0.0146, p < 0.05, respectively). Of note, 54 of 76 patients (71%) who followed up had never seen a urologist before and 40 of 61 patients (66%) with a history of nephrolithiasis followed up with a urologist. Conclusions: Inpatient urologic consultation for patients admitted to a CDU with uncomplicated ureterolithiasis undergoing stone observation does not affect outpatient urologic follow-up rates.Additionally, patients with a history of nephrolithiasis were less likely to follow up suggesting these patients may be more comfortable with outpatient MET. Based on these results, in person consultation by a urologist is likely not necessary to ensure follow up in patients with uncomplicated ureterolithiasis and may represent an area to improve overuse of urgent inpatient specialty care. Risk Factors for Polymicrobial Stones in Patients Undergoing PCNL William C. Daly, BS 1 , Erin Santos, PA-C 2 , Christopher Stockdale, MD 2 , Johann Ingimarsson, MD 2 1 MaineMedicalCenterResearchInstitute,Center forOutcomesResearchandEvaluation,Portland, ME; 2 Maine Medical Center Department of Urology, Portland, ME Introduction: Numerous studies have shown discordance between voided urine culture (UC) and stone culture (SC). This study sought to determine the correlation between polymicrobial stones and sepsis following percutaneous nephrolithotomy, and given poor concordance between UC and SC, other predicting factors for polymicrobial stones in patients undergoing PCNL. Materials & Methods: Retrospective chart review was performed on 153 consecutive patients who underwent PCNL at Maine Medical Center between October 2016 and December2018. Patient demographic factors, comorbidities, infection history, culture data, stone factors and surgical factors were recorded. Sepsis was defined by SIRS criteria for severe sepsis. Multivariate logistic regression was used to evaluate categorical variables. Results: 17 of 153 (11%) patients were found to have polymicrobial stones. Of those, 7 (41%) developed post-operative sepsis as compared to 3/33 (9%) in single organism stones and 4/103 (4%) in sterile stones. Presence of polymicrobial stone was significantly associated with post-op sepsis (OR 18, p = 0.001). Diabetes (OR 7.7; p = 0.003), neurogenic bladder (OR 11.7; p = 0.001) a history of urosepsis (OR 6.5; p = 0.005), stone diameter >= 26 mm (OR 3.8; p = 0.026), and infected stone as indication (OR 9.08; p = 0.001) were all independently associatedwith polymicrobial stone. Limited upper or lower extremitymobility (OR 31; p < 0.001), neurologic disease (OR 8.95; p = 0.001) (specifically multiple sclerosis (MS) (OR 6.3; p = 0.040)) and contractures (OR 55; p = 0.002) were associated with polymicrobial stones. While indication for PCNL because of infected stone, or having any positive pre-op urine culture had high specificity and negative predictive value for predicting polymicrobial stone, positive predictive value was low (0.27 and 0.19, respectively) (Table 1). However, combining these with information on DM, MS, spina bifida, ileal conduit or limited lower extremity mobility resulted in high positive predictive values, negative predictive value and specificity (Table 1). Conclusions: Patients with polymicrobial stones have a substantially higher risk of post PCNL sepsis compared to stones with a single or no microbe species. There are a number of easily identifiable patient attributes significantly associated with polymicrobial stones. These allow for simple risk stratification to help identify PCNL patients at higher risk for polymicrobial stone and therefore sepsis and have implications for instituting modified treatment strategies such as broader peri-operative antibiotics. Further research is needed to study the effect of these strategies. 19 18 9 Scientific Session II: Stones I