Abstract
Introduction: We aimed to validate Guy Scoring System(GSS) to predict treatment success and complications in patients who underwent percutaneous nephrolithotomy for kidney stones.
Materials and Methods: We retrospec-tively analyzed 568 patients who underwent PNL from January 2012 to August 2015 at Izmir Bozyaka Research And Training Hos-pital Urology Department for kidney stones. 60 patients who had multiple (two or more) access tracts were excluded from the study and 1 patient was excluded because of death while operating. All patients were evaluated with non-contrast spiral abdomen computed tomography (CT) scan before the operation.
All patients analysed with direct urinary system graphs (DUSG) after one month from the surgery. Patients who had symptoms or opacity in DUSG were evaluated with urinary system USG and patients who had nonopac-ity stones were evaluated with abdomen CT scan. Patients who had no symptoms or less than 4 mm renal calculi were accepted stone free.
All patients evaluated one by one with GSS. Stone-free status, operation time, fluo-roscopy time and length of hospital stay were correlated with GSS. Postoperative compli-cations were scored with Modified Clavien scoring systems and correlated with GSS.
Results: The mean Guy stone score was 2,08±0,9 Overall stone free rates was 394 (%77.9). The mean stone size is calculated 502,01 ± 517,5 (55-2869) mm². 112 (%22,1) of the patients had residue stone.
There were a positive correlation between GSS with stone-free rates (p<0,01) and complication rates (p=0,004). There was also statistically significant between GSS with operative time (p<0,01), stone burden (p<0,01) and length of hos-pital stay (p=0,02).
The total number of patients who develop complications were 159 (32.5%).There was statistically significant between GUY scor-ing system and complications.
In addition, cut-off value of GSS which was calculated with youden index method for stone-free and complication were 2.5 (sensitivity %78.4, specificity %51,8), 2.5 (sensitivity %75.7, speci-ficity %37.5) respectively. Cut-off value of stone burden for stone-free was 423 mm2. At 423 mm2, sensitivity and specificity were % 52,7 and %73 respectively. Cut-off value with stone burden for pre-dict complications was 1177 mm2. At 1177 mm2, sensitivity and specificity for complications were %21,7 and %93,5 respectively.
Conclusion: We think that the scoring systems is important for standardization of study about PNL and inform to patients for com-plication and stone-free rates. GSS was found effective and adequate to show prediction of complications and stone-free status.
Keywords: Percutaneous Nephrolithotomy, Guy scoring sys-tem, Modification Clavien score system, Stone-free status
Abstract
Abstract
Introduction: We aimed to validate Guy Scoring System(GSS) to predict treatment success and complications in patients who underwent percutaneous nephrolithotomy for kidney stones.
Materials and Methods: We retrospec-tively analyzed 568 patients who underwent PNL from January 2012 to August 2015 at Izmir Bozyaka Research And Training Hos-pital Urology Department for kidney stones. 60 patients who had multiple (two or more) access tracts were excluded from the study and 1 patient was excluded because of death while operating. All patients were evaluated with non-contrast spiral abdomen computed tomography (CT) scan before the operation.
All patients analysed with direct urinary system graphs (DUSG) after one month from the surgery. Patients who had symptoms or opacity in DUSG were evaluated with urinary system USG and patients who had nonopac-ity stones were evaluated with abdomen CT scan. Patients who had no symptoms or less than 4 mm renal calculi were accepted stone free.
All patients evaluated one by one with GSS. Stone-free status, operation time, fluo-roscopy time and length of hospital stay were correlated with GSS. Postoperative compli-cations were scored with Modified Clavien scoring systems and correlated with GSS.
Results: The mean Guy stone score was 2,08±0,9 Overall stone free rates was 394 (%77.9). The mean stone size is calculated 502,01 ± 517,5 (55-2869) mm². 112 (%22,1) of the patients had residue stone.
There were a positive correlation between GSS with stone-free rates (p<0,01) and complication rates (p=0,004). There was also statistically significant between GSS with operative time (p<0,01), stone burden (p<0,01) and length of hos-pital stay (p=0,02).
The total number of patients who develop complications were 159 (32.5%).There was statistically significant between GUY scor-ing system and complications.
In addition, cut-off value of GSS which was calculated with youden index method for stone-free and complication were 2.5 (sensitivity %78.4, specificity %51,8), 2.5 (sensitivity %75.7, speci-ficity %37.5) respectively. Cut-off value of stone burden for stone-free was 423 mm2. At 423 mm2, sensitivity and specificity were % 52,7 and %73 respectively. Cut-off value with stone burden for pre-dict complications was 1177 mm2. At 1177 mm2, sensitivity and specificity for complications were %21,7 and %93,5 respectively.
Conclusion: We think that the scoring systems is important for standardization of study about PNL and inform to patients for com-plication and stone-free rates. GSS was found effective and adequate to show prediction of complications and stone-free status.
Keywords: Percutaneous Nephrolithotomy, Guy scoring sys-tem, Modification Clavien score system, Stone-free status