American Urological Association (AUA) guidelines recommend percutaneous nephrolithotomy (PCNL) for total stone burden greater than 20mm, yet it is unclear if the number of stones affects adherence to this guideline. We aim to assess the impact of stone multiplicity on the choice of ureteroscopy (URS) versus PCNL as a first line therapy for patients with high burden (>20mm), and examine whether AUA guideline-discordant care impacts patient outcomes.
Data was collected from the Registry for Stones of the Kidney and Ureter (ReSKU) database, a prospectively collected registry of patients with stones disease. Multivariate logistic regression (MLR) was used to estimate the association between stone multiplicity and the decision to perform URS for high stone burden (>20mm) patients. MLR was further used to estimate the association between performing URS and the following outcomes: stone-free rate, need for second operation, and complications. Post-operative hospital stay was compared between patients receiving URS versus PCNL using student's t-test.
125 patients were included in this analysis. For patients with total stone burden exceeding 20mm, those with more than 3 stones had roughly nine-times the likelihood of undergoing URS over PCNL compared to patients with a single stone (aOR 9.21, 95% CI 2.55 - 40.58, p = 0.001). Stone-free rates, Clavien-Dindo scores, and frequency of second-look operations did not differ significantly between URS and PCNL patients. URS patients were discharged an average of 1.26 days earlier than patients who received PCNL (95% CI 0.72 - 1.81, p<0.001).
Stone multiplicity strongly predicts which patients with stone burden >20mm will undergo URS and which will undergo PCNL. These deviations from AUA guidelines do not appear to worsen patient outcomes. These results suggest that careful consideration of each patient may warrant deviation from guidelines.
Journal of endourology. 2019 May 02 [Epub ahead of print]
Samuel Zetumer, Scott Wiener, David Bayne, Manuel Armas-Phan, Samuel L Washington, David T Tzou, Marshall Stoller, Thomas Chi
University of California San Francisco, School of Medicine , 500 Parnassus Ave , San Francisco, California, United States , 94143 ; ., University of California San Francisco, Urology, San Francisco, California, United States ; ., University of California San Francisco, Urology , 400 Parnasus Avenue, A610 , San Francisco, California, United States , 94143 ; ., University of California San Francisco, School of Medicine, San Francisco, California, United States ; ., University of California San Francisco, Urology, San Francisco, California, United States ; ., University of California San Francisco, 8785 , 400 Parnassus Avenue , San Francisco, California, United States , 94143 ; ., University of California San Francisco, Urology, San Francisco, California, United States ; ., University of California San Francisco, Urology , 400 Parnassus Ave , 6th floor Urology Clinics A638 , San Francisco, California, United States , 94143 ; .