Analysis of factors affecting re-admission after retrograde intrarenal surgery for renal stone

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To investigate the factors associated with hospital readmission (HR) after retrograde intrarenal surgery (RIRS) among renal stone patients.


The study included patients who underwent RIRS from June 2011 to December 2017. Patients who were readmitted due to surgery-related complications were evaluated retrospectively. Patient demographics including age, medical comorbidity, body mass indices, ASA score, perioperative parameters and stone factors were compared with total cohorts. HR was defined as visits to the Emergency Room or unplanned admission within 30 days after discharge. The factors affecting HR rates were analyzed using uni- and multi-variate analyses.


A total of 572 patients were enrolled into the study. The mean age was 57.6 ± 14.1 years and the mean stone diameter was 13.4 ± 6.2 mm. The mean complication rate was 6.1% and the median hospitalization time was 2.1 ± 3.4 days. HR occurred in 20 patients (3.5%). Compared to non-admission patients, readmitted patients had a higher rate of bilateral RIRS (20.0% vs 12.2%, p = 0.035), number of stones (4.65 vs 2.2, p = 0.041) and higher stone complexity score (4.15 vs 2.11, p = 0.003). Multivariate analysis showed bilateral RIRS (OR 1.091, p = 0.031) and stone complexity (OR 1.405, p = 0.003) were significant factors to predict re-admission after RIRS.


Patients with complex renal stones or those who underwent bilateral RIRS were more likely to have a higher rate of re-admission. Proper perioperative management to prevent complications should be planned based on these predictive factors.

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Extracorporeal shock wave lithotripsy


Percutaneous nephrolithotomy


Retrograde intrarenal surgery


Stone-free rates


Hospital readmission


Emergency room


Seoul National University Renal Stone Complexity score


American Society of Anesthesiologists


Body mass index


Odds ratio




Urinary tract infection


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This work was supported by Grant no. SNUBH-02-2016-015 from the SNUBH (Seoul National University Bundang Hospital) Research Fund and supported by Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education (2014R1A1A2069658).

Author information




TJK, IJL, JJO: protocol development, data collection, data analysis, manuscript writing; TJK, IJL, HML, JKL: data collection; TJK, IJL: protocol development, data collection; JJO, CWJ, SKH, SSB: project development, protocol development, data collection, data analysis, manuscript editing.

Corresponding author

Correspondence to Jong Jin Oh.

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All authors have no conflict of interest with any institution or product.

Ethical approval

All procedures performed in our study involving human participants were in accordance with the ethical standards of the institutional and national research committee and with the 1964 Helsinki Declaration and its later amendments.

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Informed consent was obtained from all individual participants included in the study.

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Kim, T.J., Lee, I.J., Lee, J.K. et al. Analysis of factors affecting re-admission after retrograde intrarenal surgery for renal stone. World J Urol 37, 1205–1210 (2019).

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  • Retrograde intrarenal surgery
  • Hospital readmission
  • Renal stone
  • Risk factor