Are there any predictors of pyonephrosis in patients with renal calculus disease?

Abstract

The objective of the study is to identify factors predicting development of pyonephrosis in patients of renal calculus disease (RCD), as this knowledge is largely unknown. Patients of RCD without pyonephrosis (Group 1) or with pyonephrosis (Group 2) presenting between December 2013 and November 2015 were evaluated. All patients of RCD who had undergone either percutaneous nephrostomy (PCN) or surgical management (percutaneous nephrolithotomy/pyelolithotomy/nephrectomy) were included. Patients treated conservatively, by extracorporeal shock-wave lithotripsy and patients of bilateral RCD were excluded. Data regarding demography, co-morbidities, associated urologic disease, previous intervention, clinical presentation, urinary culture, renal function, grade of hydronephrosis, stone characteristics were collected. 501 patients were included (Group 1: 410; Group 2: 91). Mean age in years (35.02 versus 35.48), sex ratio (2.12:1 versus 2.25:1) and mean body mass index (kg/m) (22.27 versus 22.15) were similar in both groups. Prevalence of diabetes mellitus (3.41% versus 3.29%, p = 1.000) was similar. Group 2 patients had longer duration of symptoms (5.77 versus 8.96 months, p < 0.0001), associated urological diseases such as ipsilateral PUJO and ureteric calculus (4.63% versus 12.08%, p = 0.0125), moderate/severe-grade hydronephrosis (49.75% versus 92.30%, p < 0.0001), presence of staghorn calculus (20.73% versus 62.63%, p < 0.0001), multiple calculi (48.29% versus 68.13% p = 0.0007) and nonfunctioning kidney (1.70% versus 71.42%, p < 0.0001) as predictors of pyonephrosis. In logistic multivariate analysis, additionally, past history of urological surgery (p = 0.044) was found associated with pyonephrosis. Our study identified some conditions associated with patients of pyonephrosis. To prove their role as risk factors we recommend further studies.

Hounsfield unit attenuation value can differentiate pyonephrosis from hydronephrosis and predict septic complications in patients with obstructive uropathy

“…Previous studies evaluated factors associated with PYO in patients with urinary stones. Patodia et al 5 , analysed a cohort of 91 patients with PYO and 410 individuals without PYO treated at a single center for urinary stone disease and showed that risk factors for pyonephrosis were delayed presentation, large stone size, severe hydronephrosis and poor renal function. Our results corroborate these findings.…”

“…In clinical practice the distinction between PYO and uninfected hydronephrosis (HYDRO) is challenging and the molecular mechanisms underlying the shift from HYDRO to PYO in the presence of urinary obstruction are poorly understood 1 , 5 . Previous studies have described various risk factors for PYO in patients with urinary stones such as long-term disease, severe HYDRO, stone size and non-functioning kidney 5 .…”

“…In clinical practice the distinction between PYO and uninfected hydronephrosis (HYDRO) is challenging and the molecular mechanisms underlying the shift from HYDRO to PYO in the presence of urinary obstruction are poorly understood 1 , 5 . Previous studies have described various risk factors for PYO in patients with urinary stones such as long-term disease, severe HYDRO, stone size and non-functioning kidney 5 . Moreover, measurement of computerized tomography attenuation values (Hounsfield Unit—HU) of the fluid in the dilated renal collecting system was found to be a useful marker for differentiating PYO from HYDRO in patients with obstructive uropathy 6 .…”

Challenges and management of laparoscopic treatment of pyonephrosis caused by calculi

“…Patodia retrospectively analyzed 501 patients with kidney stones and found that some factors were closely associated with the occurrence of pyonephrosis, including larger stone volume, severe hydronephrosis, poor renal function, past history of urological surgery, and obstruction caused by other causes than stones [5]. These are considered bene cial in determining which patients with kidney stones are prone to pyonephrosis.…”

Challenges and management of laparoscopic treatment of pyonephrosis caused by calculi

“…However, there is no clear predictive model demonstrating the occurrence of pyonephrosis in patients with kidney stones. Patodia retrospectively analyzed 501 patients with kidney stones and found that some factors were closely associated with the occurrence of pyonephrosis, including larger stone volume, severe hydronephrosis, poor renal function, past history of urological surgery, and obstruction caused by other causes than stones [5]. These are considered bene cial in determining which patients with kidney stones are prone to pyonephrosis.…”