Home > Riviste > Minerva Urology and Nephrology > Fascicoli precedenti > Minerva Urology and Nephrology 2021 August;73(4) > Minerva Urology and Nephrology 2021 August;73(4):525-31

ULTIMO FASCICOLO
 

JOURNAL TOOLS

eTOC
Per abbonarsi
Sottometti un articolo
Segnala alla tua biblioteca
 

ARTICLE TOOLS

Publication history
Estratti
Permessi
Per citare questo articolo
Share

 

ORIGINAL ARTICLE   

Minerva Urology and Nephrology 2021 August;73(4):525-31

DOI: 10.23736/S2724-6051.20.04055-2

Copyright © 2020 EDIZIONI MINERVA MEDICA

lingua: Inglese

Development and validation of a simple stone score to estimate the probability of residual stones prior to percutaneous nephrolithotomy

Ahmed M. HARRAZ , Ahmed R. EL-NAHAS, Mohamed A. NABEEH, Mahmoud LAYMON, Khalid Z. SHEIR, Hamdy A. EL-KAPPANY, Yasser OSMAN

Urology and Nephrology Center, University of Mansoura, Mansoura, Egypt



BACKGROUND: The aim of the present study was to develop and internally validate a simple stone score (SSS) to estimate the probability of clinically significant residual fragments (CSRF) prior to percutaneous nephrolithotomy (PNL).
METHODS: The files of 1170 PNL procedures between January and December 2015 were evaluated. CT-derived stone characteristics were examined. Caliceal stone distribution (CSD) was assigned three grades based on the number of calices involved regardless of the renal pelvis (I = no or single calix; II = more than one calix; and III = more than 2 calices or complete staghorn stones). CSRF was defined as any residuals >4 mm in postoperative CT. A logistic regression model to predict the CSRF was fitted, and coefficients were used to develop the SSS. The SSS was validated by discrimination, calibration, and decision curve analysis (DCA).
RESULTS: Patients’ data were split into training (936, 80%) and validating (234, 20%) datasets. In the training partition, independent predictors of CSRF were CSD-grade II (OR: 4.2; 95%CI: 2.5-7; P<0.001), grade III (OR: 7.8; 95%CI: 4.2-14.4; P<0.001) and largest stone diameter (LSD) (OR:1.3; 95%CI: 1.1-1.6; P<0.001). Score points 0, 1, 2, and 0, 3, 9 were given to LSD<30, 30-40, >40 mm, and CSD grades I, II, III, respectively. Discrimination of the SSS was 0.79 and after 10-fold cross-validation and internal validation was 0.86. The calibration plot and DCA highlighted the validity and clinical significance of the SSS.
CONCLUSIONS: The novel SSS could be used to describe the risk of CSRF prior to PNL. Further studies are invited for external validation.


KEY WORDS: Nephrolithotomy, percutaneous; Urology; Calculi

inizio pagina