Recoverability Of Renal Function Research Articles

The importance of preoperative evaluation to predict the outcome of percutaneous nephrostomy

Abstract: Percutaneous nephrostomy (PCN) is an invasive procedure equal to a grade 4 penetrating kidney trauma. It should be carefully considered whether has a greater benefit or risk. There are currently no parameters or scores to predict the outcome of nephrostomy in our center. This study aimed to conduct a review to find out whether there were parameters or scores that could be used to predict the outcome of nephrostomy. This research used relevant studies obtained from Clinical Key, PubMed, Semantic Scholar, Dimensions, and Science Direct published in the last 10 years and written in English. Studies on children and transplant cases were excluded. Studies that met the PICO criteria were selected. The results showed that of the 141 articles collected, and filtered with inclusion criteria, exclusion criteria, and PICO criteria, finally the remaining were three studies selected. The studies discussed about classification, SFU grading system, and complication of nephrostomy; significant variables affecting recoverability of renal function; patients’ characteristics and outcomes of double J ureteral stenting (DJS) and PCN; and 12-month-post-operative creatinine level change. Most patients who failed DJS had increased creatinine level. However, one of the indications for a nephrostomy was stenting failure. In conclusion, predictor factors that can affect the renal recovery after nephrostomy include kidney shape and size, pre-nephrostomy creatinine levels, urine output, state of infection, and degree of hydronephrosis. However, the evidence is still not enough. Further research is needed on the predictor factors for renal recovery after nephrostomy. Keywords: percutaneous nephrostomy; hydronephrosis; kidney function; predictors

Recoverability of Renal Function after Treatment of Adult Patients with Unilateral Obstructive Uropathy: A Prospective Study

Background: Obstructive uropathy refers to any blockage of urine drainage at any level of the urinary tract. It may be chronic or acute and may occur unilateral or bilateral. The prediction of the recoverability of kidney function after treatment of unilateral obstructive uropathy is of great clinical value to the urologists and nephrologists as it may affect the decision of treatment. Objectives: To detect changes in split renal function of unilaterally obstructed kidney after a period of 6 weeks of drainage. Patients and methods: This prospective observational study included 66 adult patients divided into 2 groups; Group A included patients with split function less than 10 % (36 patients) and Group B included patients with split function of 10 % or more (30 patients). Results: The study showed that there were an insignificant difference between the two groups in age, sex, cause of obstruction, laterality of obstruction, method of drainage and patient’s presentation. Also, there was an insignificant difference between pre- and post-drainage for group A (P-value 0.142). While there was a highly significance difference between pre- and post-drainage for group B (P-value < 0.001). Conclusion: the preoperative split function of the obstructed kidney is the independent factor affecting the recoverability of renal function. Where kidneys with split function less than 10% are irreversibly damaged and the decision of treatment can be taken with no need to do drainage followed by repeating renal scan. While stabilization or improvement of renal function is expected after relief of obstruction in kidneys with split function of 10% or greater.

Recoverability of Renal Function after Treatment of Adult Patients with Unilateral Obstructive Uropathy: A Prospective Study

Background: Obstructive uropathy refers to any blockage of urine drainage at any level of the urinary tract. It may be chronic or acute and may occur unilateral or bilateral. The prediction of the recoverability of kidney function after treatment of unilateral obstructive uropathy is of great clinical value to the urologists and nephrologists as it may affect the decision of treatment. Objectives: To detect changes in split renal function of unilaterally obstructed kidney after a period of 6 weeks of drainage. Patients and methods: This prospective observational study included 66 adult patients divided into 2 groups; Group A included patients with split function less than 10 % (36 patients) and Group B included patients with split function of 10 % or more (30 patients). Results: The study showed that there were an insignificant difference between the two groups in age, sex, cause of obstruction, laterality of obstruction, method of drainage and patient’s presentation. Also, there was an insignificant difference between pre- and post-drainage for group A (P-value 0.142). While there was a highly significance difference between pre- and post-drainage for group B (P-value < 0.001). Conclusion: the preoperative split function of the obstructed kidney is the independent factor affecting the recoverability of renal function. Where kidneys with split function less than 10% are irreversibly damaged and the decision of treatment can be taken with no need to do drainage followed by repeating renal scan. While stabilization or improvement of renal function is expected after relief of obstruction in kidneys with split function of 10% or greater.

Effect of losartan on the recoverability of renal function in anuric and oliguric patients with a solitary obstructed kidney: a double-blind randomized placebo-controlled trial.

To assess the role of the angiotensin receptor blocker losartan on the recoverability of renal function after de-obstruction in patients with anuria and oliguria. This was a double-blind randomized placebo-controlled trial in anuric or oliguric patients with calcular obstruction of solitary kidney. Patients with an anomalous kidney or those with an American Society of Anesthesiology score of >3 were excluded. After relief of obstruction, patients were allocated to receive either losartan potassium 25mg or placebo for 3months. Serum creatinine (sCr) and renographic glomerular filtration rate (GFR) were measured at nadir and after 3months. Changes in sCr and renographic GFR were calculated by subtracting the values at nadir from those at 3months. Improvement, stabilization or deterioration of sCr and renographic GFR were defined as percentage increase or decrease from nadir ≥10%, while changes <10% were considered as stabilization. A total of 76 patients completed 3months of follow-up. Demographics and peri-operative data were comparable in the two groups. The median (range) sCr change was -1.05 (-1.8, 0.4) and -0.5 (-1.3, 0.1) mg/dL in the losartan and placebo, groups, respectively (P = 0.07). In the losartan group, renographic GFR had improved in 26 (59.1%) and deteriorated in six (13.6%) patients, while, in the placebo group, it had improved in eight (25%) and deteriorated in 10 patients (31.3%; P = 0.01). Losartan also enhanced renographic GFR improvement vs placebo by a median (range) of 6.9 (-9, 44) vs 1.4 (-10, 32) mL/min (P = 0.004). In patients with anuria and oliguria, losartan treatment contributes to renal function recoverability after relief of calcular obstruction of the solitary kidney.

Functional outcomes after pyeloplasty in solitary kidneys: structured analysis with the implication of Acute Kidney Injury Network (AKIN) staging criteria to predict long-term renal function recoverability.

To assess the long-term functional outcomes after pyeloplasty in solitary kidney (SK) models and to define factors affecting postoperative renal function recoverability in adults. We retrospectively evaluated all adult patients who underwent pyeloplasty for pelvi-ureteric junction obstruction (PUJO) in SK. Long-term renal function was assessed by diuretic scintigraphy and morphological changes were also determined, e.g. renal parenchymal volume (RPV) and parenchymal thickness (PT). We considered a >20% increase in glomerular filtration rate (GFR) as improvement, >20% decrease as deterioration, and changes within 20% as stationary renal function. Univariate and multivariate analysis for factors affecting renal function recoverability, including the Acute Kidney Injury Network (AKIN) Staging System postoperatively, were performed. The study included 62 patients with a mean (SD) age of 29(10.5)years. At a median of 48months, the mean (SD) GFR increased from 41.3(17) to 48.5(20.1)mL/min (P<0.001), with a significant increase in RPV and PT (P=0.02 and P=0.001, respectively). Follow-up renal function was static, improved and decreased in 39 (63.4%), 17 (27%) and six (9.6%) patients, respectively. Functional success was achieved in 90.4%. Patient's age ≥39years, PT ≤0.75cm and higher early postoperative AKIN staging were predictors associated with a 4.8-, 3.2- and 2.7-fold deterioration in renal function. Pyeloplasty in SK preserved renal function in 90.4% of the present patients. Pyeloplasty in SK when associated with older age, decreased PT preoperatively, and early higher AKIN staging postoperatively was associated with poor renal function recoverability.

The Effect of Losartan on the Recoverability of Renal Function in Anuric and Oliguric Patients With Unilateral Obstructed Kidney

The Effect of Losartan on the Recoverability of Renal Function in Anuric and Oliguric Patients With Unilateral Obstructed Kidney

OUTCOME OF PEDIATRIC PYELOPLASTY IN RENAL UNITS WITH SPLIT RENAL FUNCTION LESS THAN 20%

Background: Prenatally diagnosed, hydronehprosis does not mean presence of decompensated obstruction and spontaneously improvement or resolution can occur postnatally. If obstruction persists, the split renal function (SRF) of the diseased kidney will dramatically decrease, and surgical intervention will be necessary. Objective: Evaluation of outcome of pyeloplasty in children with ureteropelvic junction obstruction (UPJO) in renal unit with split function less than 20% and to asses renal function recoverability. Patients and Methods: Cohort (historical and concurrent) study included 88 patients with UPJO with split renal function (SRF) < 20%. Preoperative patient was investigated by abdominopelvic ultrasound, magnetic resonance urography (MRU) or computerized tomography and renal isotope scan. Split renal function and T 1/2 .Preoperative and postoperative were compared. Results of the procedure were evaluated by clinical examination, abdomino-pelvic ultrasound after one month. Urine analysis with culture and sensitivity and renal isotope scan after 6 months. Results: Our study included 88 patients divided into two groups according to SRF (group 1, SRF >20% and group 2, SRF < 20%). Mean preoperative SRF was 31.34 ± 15.27%in all cases, 41.79 ± 7.03% in group 1 and 13.06 ± 4.90% in group 2, which increased postoperatively to 38.35 ± 15.61%, 46.86 ± 8.43% and 20.81 ± 7.67% respectively and this improvement was highly significant. Group 2 included 9 patient with SRF < 10%, mean preoperative SRF was 6.21 ± 2.26% which increased preoperatively to 15.04 ± 7.09% , also in the remaining 23 cases, mean preoperative SRF was 15.74 ± 2.30% increased postoperatively to 23.07 ± 6.75% . Conclusion: Poorly functioning renal unit with SRF < 20%, can show functional improvement and recoverability, so in these renal units, we should not have to rush to nephrectomy and instead of that we can proceed to pyeloplasty.

OUTCOME OF PEDIATRIC PYELOPLASTY IN RENAL UNITS WITH SPLIT RENAL FUNCTION LESS THAN 20

Background: Prenatally diagnosed, hydronehprosis does not mean presence of decompensated obstruction and spontaneously improvement or resolution can occur postnatally. If obstruction persists, the split renal function (SRF) of the diseased kidney will dramatically decrease, and surgical intervention will be necessary. Objective: Evaluation of outcome of pyeloplasty in children with ureteropelvic junction obstruction (UPJO) in renal unit with split function less than 20% and to asses renal function recoverability. Patients and Methods: Cohort (historical and concurrent) study included 88 patients with UPJO with split renal function (SRF) < 20%. Preoperative patient was investigated by abdominopelvic ultrasound, magnetic resonance urography (MRU) or computerized tomography and renal isotope scan. Split renal function and T 1/2 .Preoperative and postoperative were compared. Results of the procedure were evaluated by clinical examination, abdomino-pelvic ultrasound after one month. Urine analysis with culture and sensitivity and renal isotope scan after 6 months. Results: Our study included 88 patients divided into two groups according to SRF (group 1, SRF >20% and group 2, SRF < 20%). Mean preoperative SRF was 31.34 ± 15.27%in all cases, 41.79 ± 7.03% in group 1 and 13.06 ± 4.90% in group 2, which increased postoperatively to 38.35 ± 15.61%, 46.86 ± 8.43% and 20.81 ± 7.67% respectively and this improvement was highly significant. Group 2 included 9 patient with SRF < 10%, mean preoperative SRF was 6.21 ± 2.26% which increased preoperatively to 15.04 ± 7.09% , also in the remaining 23 cases, mean preoperative SRF was 15.74 ± 2.30% increased postoperatively to 23.07 ± 6.75% . Conclusion: Poorly functioning renal unit with SRF < 20%, can show functional improvement and recoverability, so in these renal units, we should not have to rush to nephrectomy and instead of that we can proceed to pyeloplasty.

Predictors of Recoverability of Renal Function after Pyeloplasty in Adults with Ureteropelvic Junction Obstruction

Background: This study aimed to identify factors predicting the recoverability of renal function after pyeloplasty in adult patients with ureteropelvic junction obstruction. Methods: We retrospectively reviewed 138 adults with unilateral renal obstruction-induced hydronephrosis and who underwent Anderson-Hynes dismembered pyeloplasty from January 2013 to January 2016. Hydronephrosis was classified preoperatively according to the Society for Fetal Urology (SFU) grading system. All patients underwent Doppler ultrasonography, excretory urography, computed tomography, and technetium-99m-diethylenetriamine pentaacetic acid radioisotope (99mTc DTPA) renography before and after surgery. Renal resistive index (RRI) and 99mTc DTPA renography were repeated at 1, 3, 6, and 12 months. Results: Multivariate analysis identified age, renal pelvic type, SFU grade, preoperative RRI, decline of RRI, and renal parenchyma to hydronephrosis area ratio (PHAR) as independent predictors of renal function recoverability after pyeloplasty. However, preoperative RRI and RRI decline were not significantly associated with recoverability of renal function in patients aged >35 years. Lower preoperative RRI, greater decline in RRI, higher PHAR, lower SFU grade, and extrarenal pelvis were associated with greater improvements in postoperative renal function. Conclusions: Preoperative differential renal function cannot independently predict the recoverability of postoperative renal function in adult patients with unilateral renal obstruction-induced hydronephrosis. SFU grade, renal pelvic type, PHAR, preoperative RRI, and decline in RRI were significantly associated with the recoverability of renal function in adult patients aged <35 years, while only SFU grade, renal pelvic type, and PHAR were significantly associated with renal function recoverability in patients aged ≥35 years. Renal function recovery was better in patients younger than 35 years when compared with older patients.

Reversibility of glomerular filtration rate after surgery for unilateral obstructive Uropathy

Introduction: Surgical treatment is increasingly finding a place in the treatment of unilateral obstructive uropathy. This study was designed to investigate the recoverability of renal function following surgical treatment of adult patients with unilateral obstructive uropathy using Lasix 99mTc-diethylenetriaminepentaacetate renography (DTPA-R) for measurement of glomerular filtration rate (GFR) before and after surgery. Methods: This was a prospective study which included 29 (20 males and 9 females) consecutive adult patients with a diagnosis of unilateral renal obstruction and a normal contralateral kidney. The obstruction and malfunction of the contralateral kidney were confirmed with Lasix DTPA-R. For all the patients, surgical treatment of the unilateral kidney obstruction was performed, and post-surgical measurement of the function of the treated kidney was also applied using Lasix DTPA-R. Results: The mean age of the patients was 42.24 years. According to our results, the average of pre-operation GFR was 17.48 ± 9.10 ml/minute/1.73 m2 and post-operation GFR was 26.4 ± 11.2 ml/minute/1.73 m2. It is approved that the GFR increased 8.92 ± 6.30 ml/minute/1.73 m2 after surgery. The most increased rate of GFR was observed in the group with the impaired kidney with GFR > 20 ml/minute. It is approved that the rate of recovery in the patients with preoperational total GFR > 75 ml/minute and also 50 10 ml/minute/1.73 m2 or total GFR > 25 ml/minute/1.73 m2 the functional recovery of damaged kidney could be expected following the removal surgery.

Evaluation of Renal Histopathological Changes, as a Predictor of Recoverability of Renal Function Following Pyeloplasty for Ureteropelvic Junction Obstruction.

Background:Pyeloplasty is a widely accepted treatment for ureteropelvic junction obstruction (UPJO). However, the renal function recoverability after pyeloplasty is still a matter of debate. Different parameters have been used to predict renal functional recoverability after corrective surgery, with conflicting results.Objectives:In this study, renal biopsy was carried on a series of cases of UPJO, during pyeloplasty, to study the extent of histological alterations in renal parenchyma, as a result of obstruction, and its predictive value in renal function recoverability after pyeloplasty.Patients and Methods:We retrospectively analyzed the renal biopsy obtained during pyeloplasty in 53 adult patients. Histopathological changes were graded on a scale of 1 to 3, according to their severity, and compared with the differential renal function (DRF) revealed on the preoperative and postoperative follow up diethylene triamine pentaacetic acid (DTPA) renal scan. A Fischer’s t test was used to evaluate statistical differences between values.Results:This study showed a linear relationship between the severity of histological changes and renal function recovery, after pyeloplasty. Out of 24 obstructed renal units (ORU), with minimal histopathological changes (grade I), 21 ORU (87.5%), with > 35% DRF preoperatively, showed significant improvement in renal function after 12 months of pyeloplasty (P < 0.05). On the other hand, all kidneys (n = 29) with moderate to severe obstructive changes (grade II and III) had minimal improvement in DRF, after pyeloplasty, which was clinically insignificant (P > 0.05). Renal function deterioration after pyeloplasty was not observed in any of the cases.Conclusions:The severity of pathological changes in renal parenchyma, due to UPJO, is a good predictor of renal function recoverability, after pyeloplasty. The ORUs, with DRF > 35%, usually have normal (grade I) renal biopsy and might be expected to present better functional recoverability after pyeloplasty.

Prognosis of obstructive nephropathy patients after percutaneous nephrostomy

Background: Percutaneous nephrostomy is a life-saving procedure for the treatment of obstructive uropathy associated with septicaemia and uraemia. It is regarded as a temporary interventional procedure before definitive treatment. Several factors can affect recovery of renal function after nephrostomy, such as patient age, duration of obstruction, function of the contralateral kidney, pyelolymphatic backflow and compliance of the ureter and renal pelvis.Objective: To determine factors that can predict the decrease in creatinine levels after percutaneous nephrostomy (&lt; 2mg/dl).Methods: This is a retrospective analysis descriptive study. All patients previously performed nephrostomy at Sardjito General Hospital Yogyakarta, from January 2009 to December 2012 were identified. The data were analyzed to evaluate the relationship between reduction of serum creatinine level and following variables including: etiology, nephrostomy (unilateral or bilateral), symptom duration (≤14 days or &gt;14 days), comorbid disease (hypertension, diabetes melitus, heart disease) and degree of hydronephrosis (mild, moderate and severe). The data were analyzed with Chi-Square test and multiple logistic regression to obtain predictive factor and predictive scoring equation to measure the possibility of recoverability of renal function after nephrostomy.Results: We analyzed 117 patients that previously treated by percutaneous nephrostomy. It showed the relationship between reduction of serum creatinine level and the following variables: nephrostomy (unilateral or bilateral) (p=0,000), symptom duration (p=0,000), hypertension (p=0,004) and degree of hydronephrosis (p=0,000). Whereas etiology of urinary obstruction and other comorbid diseases showed no relationship. Predictive equation result: P= 1/(1+ey), where y= -0,271 + 1,636 (degree of hydronephrosis) + ((-2,216) unilateral or bilateral nephrostomy) + 1,694 (symptom duration) + ((-0,862) hypertension), with sensitivity 74,3% and specificity 70,7% in predicting renal function recoverability.Conclusions: Bilateral or unilateral nephrostomy, symptom duration, hypertension and degree of hydronephrosis are factors affecting the decrease in serum creatinine level. They role as independent predictor to predict recoverability of renal function can be considered. Key words: obstructive uropathy, percutaneous nephrostomy, multiple logistic regression.

Factors influencing recoverability of renal function after urinary diversion through percutaneous nephrostomy.

Context:Various factors predict recoverability of kidney function preoperatively. Placement of percutaneous nephrostomy (PCN) and measuring the differential creatinine clearance (diff. %CrCl) is still regarded as a simple and reliable method.Aims:The aim was to evaluate correlation between renal cortical thickness (CT), hydronephrosis, intrapelvic pressure (IPP), PCN output, renal morphological factors such as length, width, echogenicity, corticomedullary differentiation (CMD), status of c/l kidney, and presence of infection which can predict recoverable function.Settings and Design:A prospective study done between July 2013 and June 2014 in Urology Department.Subjects and Methods:Hundred and sixty patients of supravesical obstruction for various causes who need PCN either due to chronic renal failure or nonvisualized kidney on contrast study, were included. IPP was measured during PCN placement. After 4 weeks 24 h urine was sent for CrCl and urine pH.Statistical Analysis Used:Correlation of continuous and categorical variables with dependent variable (diff. %CrCl) was formulated using spearman correlation and Mann–Whitney U test. Simple and multiple linear regression analysis were performed.Results:The study includes 160 patients with median age of 65.5 years. Hydronephrosis were due to stone in 76 (47.5%), pelviureteric junction obstruction (PUJO) in 40 (25%), cancer in 32 (20%), others in 12 cases (7.5%). IPP was <10 cm H2O in 48 (30%); 10–20 cm H2O in 64 (40%) and >20 cm H2O in 48 (30%). There was significant correlation between IPP and diff. %CrCl with correlation coefficient ρ = 0.509 (P = 0.0001).Conclusions:CT, parenchymal echogenicity, CMD, pre-PCN creatinine, and status of c/l kidney are the only independent variables which can predict the renal function while other variables like renal size, urine output, infection, hydronephrosis lost their statistical significance in multivariate analysis. Furthermore, IPP measured before PCN directly correlated with daily urine output and diff. %CrCl.

Evaluation of Factors Predicting Recoverability of Renal Function after Pyeloplasty in Adults

Aim: To analyze the status of renal function after pyeloplasty in a large contemporary adult series and to detect which variables predict improvement of renal function. Materials and Methods: 85 adult patients were retrospectively identified who had undergone pyeloplasty between January 2002 and May 2011 with available pre- and postoperative diuretic scintigraphy. Preoperative differential renal function (DRF) and single-kidney GFR (SKGFR) were obtained by ^99mTc-MAG-3 diuretic scintigraphy. Baseline-weighted (bw-) DRF and SKGFR were calculated between baseline conditions and time of last follow-up. Factors that explain the variance of bw-DRF and bw-SKGFR were determined. Results: The mean (SD) preoperative DRF significantly increased from 34% (11.6) to 37.2% (11.8) after pyeloplasty (p < 0.001). Similarly, mean (SD) SKGFR showed a significant improvement from 31.2 (12.9) to 35.9 (15) ml/min (p < 0.001). Patients with a lower baseline DRF (≤40%) showed a significant improvement as opposed to those with a higher baseline DRF (>40%) (p < 0.001 and 0.3, respectively). Baseline DRF and cortical thickness explained the variance in bw-DRF and bw-SKGFR with more contribution of baseline DRF. Conclusions: Renal function showed improvement after pyeloplasty in adults and preoperative DRF and cortical thickness were the predicting variables.

MP27-10 FACTORS PREDICTING RECOVERABILITY OF RENAL FUNCTION AFTER RELIEF OF OBSTRUCTIVE UROPATHY SECONDARY TO BENIGN DISEASES: DOES THE METHOD OF DRAINAGE MATTER?

INTRODUCTION AND OBJECTIVES: We aim at determining factors predicting recoverability of renal function after relief of obstruction with special emphasis on the method of drainage. METHODS: We retrospectively analyzed 137 adult patients with solitary kidneys presented with obstructive oliguria or anuria because of stone and/or stricture diseases and underwent temporal drainage by either PCN or JJ stents between January 2011 and June 2013. Patients< 18 years, or with obstruction because of malignancy or those underwent definitive intervention in the emergency setting were excluded. The primary outcome is the rate of decline of serum creatinine (SCr) after drainage of obstruction. The impact of method of drainage and other potential factors on the primary outcome were determined using univariate and multivariate analyses. RESULTS: A total of 127 patients showed a median (range) decline of SCr of 0.7 (0.05-2.7) mg/dl/day while 10 patients showed no change or rise of SCr and thereby excluded from the analysis. The rate of SCr decline showed non-significant association with gender, duration of obstruction, presence of diabetes mellitus or hypertension or the method of drainage. One the other hand, the rate of SCr decline showed significant correlation with SCr at presentation (r 1⁄4 0.4; p 1⁄4 0.001), urine culture (r 1⁄4 -0.262; p 1⁄4 0.005), fever after drainage (r 1⁄4 -0.225; p 1⁄4 0.017), baseline hemoglobin level (r 1⁄4 0.226; p 1⁄4 0.016) and number of previous episodes of obstructive uropathy (r 1⁄4 -0.251; p 1⁄4 0.007). On multivariate analysis, SCr at presentation (beta 1⁄4 0.308, p 1⁄4 0.001), hemoglobin level (beta 1⁄4 0.248, p 1⁄4 0.004), episodes of previous obstructive uropathy (beta 1⁄4 -0.198, p 1⁄4 0.019) and urine culture (beta 1⁄4 -0.198, p 1⁄4 0.02) were independent predictors of the rate of SCr decline. CONCLUSIONS: The method of temporal drainage of obstructive uropathy does not matter. Higher SCr and Hemoglobin levels at presentation are associated with rapid recovery of renal function while previous episodes of obstructive uropathy and positive urine culture slow down the recovery process.

MP27-11 SLOW DELIVERY RATE VERSUS RAPID DELIVERY RATE SHOCK WAVE LITHOTRIPSY (SWL) FOR PEDIATRIC RENAL UROLITHIASIS: A PROSPECTIVE RANDOMIZED STUDY

INTRODUCTION AND OBJECTIVES: We aim at determining factors predicting recoverability of renal function after relief of obstruction with special emphasis on the method of drainage. METHODS: We retrospectively analyzed 137 adult patients with solitary kidneys presented with obstructive oliguria or anuria because of stone and/or stricture diseases and underwent temporal drainage by either PCN or JJ stents between January 2011 and June 2013. Patients< 18 years, or with obstruction because of malignancy or those underwent definitive intervention in the emergency setting were excluded. The primary outcome is the rate of decline of serum creatinine (SCr) after drainage of obstruction. The impact of method of drainage and other potential factors on the primary outcome were determined using univariate and multivariate analyses. RESULTS: A total of 127 patients showed a median (range) decline of SCr of 0.7 (0.05-2.7) mg/dl/day while 10 patients showed no change or rise of SCr and thereby excluded from the analysis. The rate of SCr decline showed non-significant association with gender, duration of obstruction, presence of diabetes mellitus or hypertension or the method of drainage. One the other hand, the rate of SCr decline showed significant correlation with SCr at presentation (r 1⁄4 0.4; p 1⁄4 0.001), urine culture (r 1⁄4 -0.262; p 1⁄4 0.005), fever after drainage (r 1⁄4 -0.225; p 1⁄4 0.017), baseline hemoglobin level (r 1⁄4 0.226; p 1⁄4 0.016) and number of previous episodes of obstructive uropathy (r 1⁄4 -0.251; p 1⁄4 0.007). On multivariate analysis, SCr at presentation (beta 1⁄4 0.308, p 1⁄4 0.001), hemoglobin level (beta 1⁄4 0.248, p 1⁄4 0.004), episodes of previous obstructive uropathy (beta 1⁄4 -0.198, p 1⁄4 0.019) and urine culture (beta 1⁄4 -0.198, p 1⁄4 0.02) were independent predictors of the rate of SCr decline. CONCLUSIONS: The method of temporal drainage of obstructive uropathy does not matter. Higher SCr and Hemoglobin levels at presentation are associated with rapid recovery of renal function while previous episodes of obstructive uropathy and positive urine culture slow down the recovery process.

Renal recoverability in infants with obstructive calcular anuria: Is it better than in older children?

ObjectiveUrolithiasis in infants can cause considerable morbidity. The literature regarding calcular anuria in this age group is very defective. Our aim was to evaluate impact of intervention on renal recoverability in these infants. Patients and methodsA series of 24 patients presenting with obstructive calcular anuria were included in this study. Mean age was 16.5 ± 6.2 months. They were treated either by initial urinary diversion or definitive endoscopic (ureteroscopy or JJ stenting with medical alkalinization) or open surgical (ureterolithotomy or pyelolithotomy) treatment. ResultsMean serum creatinine was 5.8 ± 2.6 mg/dl. Initial peritoneal dialysis and/or urinary diversion was needed in 11 patients (45.8%). Open surgical treatment was applied in 5 (20.8%), endoscopic treatment was applied in 15 (62.5%), while combined treatment was applied in 4 (16.6%) patients. All patients had normal serum creatinine on discharge. Three (12.5%) had residual stones which were cleared by 2ry ureteroscopic intervention at 6 months. The overall complication rate in this study was 12.5% in the form of postoperative leakage (1) and postoperative fever (2). No mortality or development of chronic renal failure was reported at 6 months follow up. In comparison with these results, a previous study carried out in our centre on an older age group had a higher complication rate (28%) with higher mortalities and lower renal function recoverability rate (94%). ConclusionsAppropriate and timely medical and surgical management of calcular anuria will mostly lead to full recovery of renal functions. In comparison with older children, renal prognosis in those less than 2 years seems more favorable.

Prospectively Estimating the Recoverability of Renal Function after Relief of Unilateral Urinary Obstruction by Measurement of Renal Parenchymal Volume

Renal parenchymal volume (RPV) has been suggested as an indicator of the potential functional residual capacity for a given kidney. The goal of this study was to determine whether the recoverability of renal function could be predicted by RPV as estimated by computed tomography (CT) before an operation. Eighty-two adult patients diagnosed with long-term chronic unilateral ureteral obstruction and a normal contralateral kidney were recruited for evaluation. RPV was measured by nonenhanced CT. Glomerular filtration rate (GFR) was measured by radioisotope renal scan. Animal models were used to validate use of the CT method to measure RPV. RPV and GFR values for all patients were obtained before surgical relief of the urinary obstruction and compared with those values obtained at 12 months postsurgery. There was no statistically significant difference found between RPV measured by CT or by the water displacement method. Among patient age, sex, and pre-RPV and pre-GFR of obstructed and contralateral kidney, pre-RPV and pre-GFR of obstructed kidney were the independent factors that best indicated recoverability of renal function. Pre-RPV correlated well with post-GFR (r = 0.68, P < .01). The cut-off point of pre-RPV to predict recoverability of renal function after the relief operation was 58.2 mL, as determined by receiver operating characteristic curve analysis. Pre-RPV was the independent factor that determines recoverability of renal function. Renal function may stabilize or improve after relief of urinary obstruction when the pre-RPV value is ≥58.2 mL.

Application of 1H NMR metabonomics in predicting renal function recoverability after the relief of obstructive uropathy in adult patients

ObjectiveTo evaluate a method for predicting renal function recoverability after the relief of obstructive uropathy using 1H NMR-based metabonomics. Design and methodsThis study included 16 bilateral ureteral obstruction (BUO) patients and 9 unilateral ureteral obstruction (UUO) patients. The obstructions in all of the patients were successfully relieved after treatment. Urine samples at different time points before and after treatment were obtained, and their 1H NMR spectra were recorded and analyzed using multivariate statistical techniques combined with quantitative statistical analyses. ResultsA distinctive pattern in the metabolite profile of urine samples from preoperation and early and late stages after treatment was observed, which was in good agreement with the clinical chemistry analyses. Some important systemic perturbations in endogenous metabolites were correlated with different recoverability stages of renal function after obstruction relief. In addition, the OPLS-DA model of BUO patients could help predict the recovery of renal function of UUO patients. ConclusionThe results suggest that 1H NMR-based metabonomics can be used to evaluate the recoverability of renal function after obstruction relief. Our results suggest that 1H NMR-based metabonomics may help stratify patients according to disease stages, provide prognostic information, and be useful for postoperative surveillance.

Recoverability of renal functions after relief of partial ureteric obstruction of solitary kidney: impact of ferulic acid

What's known on the subject? and What does the study add? It is known that the kidney damage continues even after release of ureteric obstruction. This study found that giving ferulic acid, antioxidant, after release of ureteric obstruction enhanced the recovery of kidney functions in solitary kidney. To evaluate the effect of ferulic acid (FA) on the recovery of renal function and renal damage after relief of partial ureteric obstruction (PUO) of a solitary kidney. Male mongrel dogs (n = 32) were classified into three groups: sham (eight), control (12) and study (12). A right nephrectomy was carried out and dogs in the study and control groups were subjected to 4 weeks of PUO. Serum creatinine, creatinine clearance (CrCl) and renographic clearance (RC) were measured at baseline, after 4 weeks of obstruction and 8 weeks after relief of obstruction. Markers of lipid peroxidation (malondialdehyde [MDA]), superoxide dismutase (SOD), and reduced glutathione (GSH), and immunostaining of markers of apoptosis (caspase 3 and Bcl2), cell proliferation (Ki67) and interstitial fibrosis in the kidney were evaluated at the end of experiment. Ferulic acid enhanced the recovery of serum creatinine, CrCl and RC by an extra 22%, 26% and 33.7%, respectively, of the basal values at 8 weeks, after relief of 4 weeks' obstruction. In addition, FA caused a significant decrease in MDA and a significant increase in GSH and SOD. Ferulic acid also significantly reduced the interstitial fibrosis, and caspase 3 expression, and significantly increased the expression of Bcl2 and Ki67 in kidney tissues at 8 weeks after relief of the obstruction. Ferulic acid enhances the recoverability of renal function and minimizes the renal damage through reduction of oxidative stress, tubular apoptosis and the interstitial fibrosis in the solitary kidney after relief of PUO.