Decrease In Differential Renal Function Research Articles

Laparoscopic Upper-pole Heminephrectomy for the Management of Duplex Kidney: Outcomes of a Multicenter Cohort

ObjectiveTo analyze the outcomes of patients undergoing upper-pole heminephrectomy surgery and to assess the different variables that may have an impact on outcome, specifically regarding morbidity and the need for further surgeries. Materials and MethodsA retrospective study of patients who underwent laparoscopic upper-pole heminephrectomy for a nonfunctional moiety between August 2007 and December 2019 was conducted at 3 centers. A total of 130 patients met the inclusion criteria. A transperitoneal approach was used. The following variables were evaluated: (1) preoperative: presentation, presence of ureterocele and history of ureterocele incision, hydronephrosis grade, presence of vesicoureteral reflux (VUR), and differential renal function (DRF) on renal scintigraphy; and (2) postoperative outcomes: Doppler ultrasound, renal scintigraphy, complications, febrile urinary tract infection, lower urinary tract symptoms, and need for further surgery. Findings were considered statistically significant at P <.05. ResultsPostoperative complications were observed in 5 patients (3.8%). Six patients (4.6%) needed further surgeries after heminephrectomy. The presence of ureterocele and VUR was related with the need for further surgeries odds ratio (OR) 4.91, P = .0415) and the occurrence of postoperative febrile urinary tract infection (OR 2.81, P = .0376). A 13.9% incidence of lower urinary tract symptoms was found with no difference between patients with ureterocele and those with an ectopic ureter. Renal scintigraphy showed a median decrease in DRF of 2.7%. No patient had complete loss of function. ConclusionLaparoscopic upper-pole heminephrectomy showed to be a feasible and safe procedure. In most patients this surgery will be the definitive procedure. Patients with both VUR and ureterocele will need special consideration. No significant loss of function in the remaining lower moiety was found.

Can urinary biomarkers detect obstruction defined by renal functional loss in antenatal hydronephrosis?

Diagnosing obstruction and thus, assessment of need for surgery in the management of antenatal hydronephrosis may be challenging. Current diagnostic tests are not capable of indicating which patients are at risk for obstructive nephropathy. Biomarkers may play an important role in distinguishing these patients. The aim of this study is to evaluate if urinary biomarkers could differentiate obstruction (OBS) from non-obstructive dilation (NOD) in patients with antenatal hydronephrosis (AH) that underwent pyeloplasty due to loss of differential renal function (DRF). Children with a history of AH and postnatal anteroposterior (AP) diameter ≥15mm were included in this study of prospectively collected data between 2010 and 2018. The OBS group included patients who underwent pyeloplasty due to solely ≥10% subsequent decrease in DRF on a MAG-3 scan during follow-up. Patients with stable or improving hydronephrosis with no significant reduction in ipsilateral DRF (<10%) during follow-up formed the NOD group. Healthy children with no history of AH and a normal urinary ultrasound were taken as the control group. Urinary IP-10, MCP-1, KIM-1, NGAL, and Ca19-9 levels using ELISA were measured. In the OBS group, urine samples were obtained preoperatively and at 3rd post operative-month whereas in the NOD and control groups, samples were collected at the time of enrollment. There were 24 children in the OBS and 27 children in the NOD groups. The control group consisted of 27 healthy children. The pre-operative bladder urine levels of biomarkers of the OBS group were significantly higher than in the NOD and control group (p<0.05, for all). In terms of differentiating OBS from NOD, results of ROC analyses for the given cut-off values were as follows: 135.06 ng/mgCr (sensitivity 75%; specificity 66%, AUC=0.735) for IP-10, 0.89 ng/mgCr (sensitivity 79.2%; specificity 88%, AUC=0.802) for KIM-1, 367.65 pg/mgCr (sensitivity 62.5%; specificity 52%, AUC=0.660) for MCP-1, 16.15 ng/mgCr (sensitivity 70.8%; specificity 70.4%, AUC=0.669) for NGAL, and 55.5 U/mgCr (sensitivity 75%; specificity 66%, AUC=0.676) for Ca 19-9. Moreover, when KIM-1 was combined with IP-10 and Ca19-9, sensitivity and specificity levels were 83% and 85% (AUC=0.919), respectively. In this novel study, which focused on scintigraphic DRF loss, KIM-1 was the most successful among all the biomarkers evaluated. Combination of IP-10, Ca19-9 and KIM-1 resulted increased diagnostic ability.

Best ultrasound parameter for prediction of adverse renal function outcome after pyeloplasty.

To evaluate the clinical value of preoperative ultrasound parameters for post-pyeloplasty outcomes in pediatric patients with ureteropelvic junction obstruction. The medical records of 187 pediatric and adolescent patients who underwent pyeloplasty as a result of ureteropelvic junction obstruction between 2010 and 2016 were retrospectively reviewed. The severity of hydronephrosis was measured by the Society for Fetal Urology grade, anteroposterior pelvic diameter, urinary tract dilation, hydronephrosis index, and the hydronephrosis area to renal parenchyma ratio at 3, 6 and 12months. Adverse renal function outcome was defined as ≥10% decrease in postoperative differential renal function compared with preoperative values. Of the 187 patients, preoperative hydronephrosis was categorized as Society for Fetal Urology grade3 in 26 patients (13.9%) and grade4 in 161 patients (86.1%). No surgical failures, defined as requirement of repeat surgery or deterioration of hydronephrosis grade, were noted. The mean changes in Society for Fetal Urology grade, anteroposterior pelvic diameter, urinary tract dilation and hydronephrosis area to renal parenchyma ratio showed similar trends of recovery during the follow-up period. In total, 19 patients (10.2%) showed >10% decrease in differential renal function during follow up (mean 42months). Multivariate logistic regression analysis showed that the hydronephrosis area-to-renal parenchyma ratio was the only significant prognostic factor for adverse renal function outcome (hazard ratio 1.806, 95% confidence interval 1.210-2.859, P=0.005). Receiver operating characteristic analysis showed that the hydronephrosis area-to-renal parenchyma ratio was the most significant predictive value (area under the curve 0.711, 95% confidence interval 0.618-0.804, P=0.006). Pediatric patients with high hydronephrosis area-to-renal parenchyma ratio values before surgery are more likely to show renal function decline after pyeloplasty.

Correction of differential renal function for asymmetric renal area ratio in unilateral hydronephrosis.

Children with unilateral hydronephrosis are followed up with anteroposterior pelvic diameter (APD), hydronephrosis grade, mercaptoacetyltriglycine (MAG-3) drainage pattern and differential renal function (DRF). Indeterminate drainage preserved DRF in higher grades of hydronephrosis, in some situations, complicating the decision-making process. Due to an asymmetric renal area ratio, falsely negative DRF estimations can result in missed optimal surgery times. This study was designed to assess whether correcting the DRF estimation according to kidney area could reflect the clinical situation of a hydronephrotic kidney better than a classical DRF calculation, concurrently with the hydronephrosis grade, APD and MAG-3 drainage pattern. We reviewed the MAG-3, dimercaptosuccinic acid (DMSA) scans and ultrasonography (US) of 23 children (6 girls, 17 boys, mean age: 29 ± 50 months) with unilateral hydronephrosis. MAG-3 and DMSA scans were performed within 3 months (mean 25.4 ± 30.7 days). The closest US findings (mean 41.5 ± 28.2 days) were used. DMSA DRF estimations were obtained using the geometric mean method. Secondary calculations were performed to correct the counts (the total counts divided by the number of pixels in ROI) according to kidney area. The renogram patterns of patients were evaluated and separated into subgroups. The visual assessment of DMSA scans was noted and the hydronephrotic kidney was classified in comparison to the normal contralateral kidney's uptake. The correlations of the DRF values of classical and area-corrected methods with MAG-3 renogram patterns, the visual classification of DMSA scan, the hydronephrosis grade and the APD were assessed. DRF estimations of two methods were statistically different (p: 0.001). The categories of 12 hydronephrotic kidneys were changed. There were no correlations between classical DRF estimations and the hydronephrosis grade, APD, visual classification of the DMSA scan and uptake evaluation. The DRF distributions according to MAG-3 drainage patterns were not different. Area-corrected DRF estimations correlated with all: with an increasing hydronephrosis grade and APD, DRF estimations decreased and MAG-3 drainage patterns worsened. A decrease in DRF (< 45 %) was determined when APD was ≥ 10 mm. When APD was ≥ 26 mm, a reduction of DRF below 40 % was determined. Our results suggest that correcting DRF estimation for asymmetric renal area ratio in unilateral hydronephrosis can be more robust than the classical method, especially for higher grades of hydronephrotic kidneys, under equivocal circumstances.

Complications After Common Sheath Reimplantation in Pediatric Patients With Complicated Duplex System

To report our experience of common sheath reimplantation (CSR) for ectopic ureterocele (EU) combined with ureteral duplication, describing success rates and postoperative complications, along with risk factors for developing postoperative incontinence. When the upper tract approach is not indicated in patients with EU, a bladder-level approach, involving either CSR or total reconstruction, is the remaining option. However, concerns exist about the high morbidity of bladder-level approaches. We retrospectively examined the postoperative results of 39 patients who underwent CSR between January 2001 and December 2012. Risk factors for the development of postoperative incontinence and decreases in differential renal function (DRF) were additionally analyzed. The median age at operation was 16.5months. After CSR, upper urinary tract dilatation decreased in 36 patients (92.3%). During a median follow-up of 75.9months, an additional operation was required in 7 patients (17.9%). Postoperative incontinence developed in 3 patients (7.7%). Median preoperative DRF was significantly lower in the postoperative incontinence group (P= .004). DRF decreased postoperatively in 5 of 36 patients (13.9%). No preoperative factors were related to the decrease in DRF. No patient developed hypertension or proteinuria. CSR decompressed the upper urinary tract effectively in our EU patients. Postoperative incontinence does not seem to be related to operation factors, but with preoperative DRF. When the upper tract approach is not indicated, CSR is a reasonable alternative. Total reconstruction isunnecessary as the remnant upper pole kidney after CSR does not lead to complications.

The risk factors and clinical significance of acute postoperative complications after unstented pediatric pyeloplasty: A single surgeon’s experience

PurposeTo analyze the risk factors and clinical significance of postoperative complications after unstented pediatric pyeloplasty. Materials and MethodsWe analyzed 285 kidney units (KUs) on which unstented pyeloplasty was performed between April 2002 and March 2010. Measures included preoperative factors, postoperative complications, change in postoperative differential renal function (DRF), and failure of pyeloplasty. Risk factors for acute complications requiring additional ureteral stenting and decreased DRF were analyzed. ResultsDuring a median follow-up period of 67.0months, an additional ureteral stenting was required in 28 KUs (9.8%) due to the development of acute postoperative complications after unstented pyeloplasty. The incidence of complications increased significantly as preoperative DRF increased. DRF of more than 60% was the only independent risk factor for acute complications. Postoperative decrease in DRF was observed in 58 KUs (22.4%) among 259 KUs analyzed. Pyeloplasty failure was observed in 10 KUs (3.5%). The development of acute complications was not a risk factor for a decrease in DRF or pyeloplasty failure. ConclusionsUrinary diversion during pyeloplasty is not related to a decrease in DRF or pyeloplasty failure. However, in patients with a preoperative DRF of greater than 60%, diversion could be considered due to the high prevalence of complications.

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There have been many reports concerning pediatric uretero-pelvic junction obstruction (UPJO). However, most of them focused on the technical aspects of operation such as the diversion method, laparoscopic pyeloplasty or robotic pyeloplasty. The natural course of UPJO or the prediction of renal outcome in individual patient has been left vague. Although decrease in differential renal function (DRF) on renal scintigraphy and the aggravation of hydronephrosis on ultrasonography have been widely accepted as indications for pyeloplasty, these indications have a fundamental limitation. Only after we encounter disease progression can we perform surgery to prevent further progression with such indication. If we could know the degree of renal injury just before it happens or predict renal function deterioration correctly, we could perform surgery before damage in some patients and also prevent unnecessary operation in other patients. Editorial CommentUrologyVol. 81Issue 4PreviewThis article attempts to address one of the most challenging problems facing pediatric urology—how to evaluate, when ureteropelvic junction obstruction seems to be present, whether surgical intervention will at least stabilize renal function, may allow improvement in ipsilateral renal function, and, most difficult of all, how to predict the potential for renal deterioration if surgery is not done. For the most part, the available data, as incomplete as it may be, has been generated from cases of unilateral obstruction, in which the contralateral normal kidney can be used as an intrinsic control. Full-Text PDF

Does Hydronephrosis After Extravesical Ureteral Reimplantation Deteriorate Renal Function?

We analyzed whether newly developed or aggravated hydronephrosis deteriorates differential renal function after extravesical ureteral reimplantation. We performed extravesical ureteral reimplantation in 93 patients with unilateral vesicoureteral reflux between January 2006 and December 2009. Excluding 3 patients with other combined disease, a retrospective cohort analysis of 90 consecutive patients was conducted. We performed ultrasonography before and 1 month after extravesical ureteral reimplantation, and dimercapto-succinic acid scan before and 6 months after extravesical ureteral reimplantation. Of the patients 83 underwent final dimercapto-succinic acid scan at 6 months postoperatively. We analyzed the preoperative studies and perioperative parameters to evaluate the factors affecting newly developed or aggravated hydronephrosis at 1 month, and decrease in differential renal function at 6 months after extravesical ureteral reimplantation. Newly developed or aggravated hydronephrosis was observed in 25 patients (28.4%) 1 month after extravesical ureteral reimplantation. Younger age at surgery was a risk factor (p = 0.003). Of the patients 23 showed improvement on ultrasound 6 months postoperatively. In 12 patients (15.7%) a decrease in differential renal function of more than 5% was observed 6 months postoperatively. Preoperative parenchymal reduction on dimercapto-succinic acid scan was the only significant factor (p = 0.008). There was no correlation between newly developed or aggravated hydronephrosis and final decrease in differential renal function (p >0.999). Although newly developed or aggravated hydronephrosis after extravesical ureteral reimplantation is common, especially in younger patients, it is transient and does not affect differential renal function. A postoperative decrease in differential renal function without further urinary tract infection could develop when there is a parenchymal reduction on preoperative dimercapto-succinic acid scan.

Observation of infants with SFU Grades 3–4 hydronephrosis: Worsening drainage with serial diuresis renography indicates surgical intervention and helps prevent loss of renal function

Purpose Early pyeloplasty is indicated for ureteropelvic junction obstruction (UPJ) obstructions with reduced differential renal function (DRF) and/or no drainage on diuretic renography (DR). Optimal management of Society of Fetal Urology (SFU) Grades 3 and 4hydronephrosis with preservation of DRF and indeterminate drainage is less straightforward. We review our experience using serial DR to guide the management of kidneys with high-grade hydronephrosis, emphasizing preservation of DRF. Methods After IRB approval we reviewed the charts of 1398 patients <1-year-old referred for prenatal hydronephrosis. Only patients with SFU Grades 3 and 4 hydronephrosis without ureterectasis were included in the study. Initial evaluation included a baseline DR. Follow-up included DR or ultrasound (US). Results 115 patients (125 kidneys) were eligible for study inclusion. 27 kidneys underwent early surgery (median 64 days) due to reduced DRF and/or severely impaired drainage. 98 kidneys were initially observed. Of these, 21 underwent delayed surgery (median 487 days) due to worsening drainage. Only 2 patients had an irreversible decrease in DRF of >5%. 77 kidneys demonstrated improved drainage and stable DRF. Comparison of observation ( n = 77) and surgery groups ( n = 48) revealed more kidneys with SFU Grade 3 hydronephrosis in the observation group ( p = 0.0001). Conclusion Infants with Grades 3 and 4 hydronephrosis and preserved DRF may be safely followed with serial DR. Patients with SFU Grade 4 hydronephosis are more likely to require surgery. Worsening drainage on serial DR is a useful indicator for surgical intervention which limits the number of pyeloplasties while preserving DRF.

Megauréter primario no refluyente detectado prenatalmente

Most primary non-refluxing megaureters resolve spontaneously and the indications for surgery are not sufficiently well established. To analyze the clinical features, treatment and outcome of asymptomatic primary non-refluxing megaureter. We retrospectively studied 58 infants with primary non-refluxing megaureter. The diagnostic methods used were renal ultrasound, renal isotopic renogram, DMSA scan, and evaluation of renal function. The mean age at postnatal diagnosis was 24 days. The mean follow-up was 4 years. Sixty-nine percent of the patients were male. Fifty-seven percent were left megaureters and 22% were bilateral (71 affected renal units). Eleven percent of megaureters were grade I, 48% were grade II, and 41% were grade III. Only nine patients (15%) received surgical treatment. The indications for surgical treatment were severe megaureter (3/9 patients; 33%), prolonged T1/2 (3/9 patients; 33%), reduced function (1/9 patients; 11%), prolonged T1/2 plus reduced function (1/9 patients; 11%) and increased dilation (1/9 patients; 11%). The mean age at surgery was 7 months. Outcomes in the non-surgical group (85% of the patients; 60 renal units) were as follows: 90% of megaureters were corrected or improved on ultrasound scan and 10% showed no change. In the first renogram, function was low in 4/60 kidneys (7%) and T1/2 was prolonged in 3/60 (5%). Finally, all kidneys in the non-surgical group had normal function, except one, which was injured from the beginning. T1/2 was normal in all kidneys. Outcomes in the surgical group (10 megaureters) were as follows: 80% of megaureters were corrected or improved after surgical intervention and 20% showed no change. At diagnosis, 4/10 kidneys (40%) had reduced function. In the post-surgical renogram 2/10 kidneys (20%) continued to show reduced function, 1/10 kidney (10%) showed restored renal function, and 1/10 kidney (10%) was nephrectomized. Initial T1/2 was prolonged in 4/10 patients (40%), and after surgery T1/2 was normal in all patients. The final DMSA scan showed 5/71 kidneys (7%) with irreversible damage (one slightly injured, two moderately injured, and three severely injured). The remaining 66 kidneys were normal. Overall renal function and blood pressure were normal in all patients. Primary non-refluxing megaureter is usually a functional and benign congenital malformation that resolves during the first months of life. Although the malformation can persist, only a few patients require surgical treatment. Most authors agree that initial treatment should not be surgical and that surgery should be reserved for patients who develop ureteral dilation, a decrease in differential renal function, and/or severe symptoms during follow-up. In a few patients (7% of our series), the renal unit belonging to the megaureter shows irreversible congenital injury. In these patients, surgery is not useful.

Delayed decrease in differential renal function after successful pyeloplasty in children with unilateral antenatally detected hydronephrosis

The aim of this study was to evaluate functional outcome of congenital hydronephrotic kidney. The records of consecutive children who underwent pyeloplasty for unilateral prenatally detected ureteropelvic junction obstruction were reviewed. Renal function was assessed renographically before and after surgery. Mean follow-up period was 100 months. Sufficient pre- and postoperative data were available for 60 children. Differential renal function (DRF) improved in 14 (23%) and decreased in nine (15%) of 60 patients in the early postoperative period. DRF improved in seven (18%) and decreased in 13 (34%) of 38 patients at the end of follow-up. Five of 14 patients with increased DRF at early postoperative scan returned to the preoperative level at the end of follow-up. No patients with decreased DRF at early postoperative scan showed any recovery in DRF and progressive decrease was seen in four of nine children. The DRF was not stable in some patients after successful pyeloplasty. In some patients impairment of renal function came to be apparent with time. Improvement of DRF may be a transient phenomenon seen in the early postoperative period. To avoid overestimation of functional recovery, long-term follow-up with delayed renographic evaluation is recommended.

Diagnóstico prenatal de hidronefrosis: utilidad del renograma isotópico diurético

To investigate the value of diuretic renography in patients with prenatally diagnosed unilateral hydronephrosis. We reviewed 44 patients who underwent ultrasonography in the first week of life and 1 month after birth, and cystography and diuretic renography at 1 month to evaluate differential renal function and the diuretic washout pattern. Patients with vesicoureteral reflux were followed-up according to the protocol for this disorder. In the remaining patients, ultrasonography and/or diuretic renography was performed every 3-6 months. In 4/44 patients vesicoureteral reflux was detected as cause a of hydronephrosis. In the remaining 40 patients, diuretic renography showed a washout pattern not suggestive of obstruction in 32 (only one patient needed surgery due to pyohydronephrosis). An indeterminate washout pattern was detected in one patient (who required surgery due to worsening of the washout pattern). A pattern suggestive of obstruction was detected in seven patients, four of whom required surgery (three due to a decrease in differential renal function and one due to worsening of the degree of pelvic dilatation). Diuretic renography is highly useful in risk stratification and in the management of newborn infants with hydronephrosis since infants with washout patterns not suggestive of obstruction will rarely develop obstructive hydronephrosis and can initially be followed-up with ultrasonography alone. In indeterminate and obstructive patterns, however, close monitoring that includes diuretic renography is mandatory.

Does delayed operation for pediatric ureteropelvic junction obstruction cause histopathological changes?

We studied histopathological changes in kidneys with demonstrable ureteropelvic junction obstruction in relation to patient age, differential renal function and urinary tract infection. Renal biopsy was performed in 42 children (44 kidneys) with a mean age of 3 years 6 months who underwent open pyeloplasty due to ureteropelvic junction obstruction. Each specimen was examined for reversible inflammatory cell infiltration and irreversible change, including interstitial fibrosis, arteriolar thickening and glomerular sclerosis. Each pathological finding was scored 0 to 3 in increasing grades of severity, and correlated with patient age, differential renal function and history of urinary tract infection. Of the 44 kidneys 20 (45%) had irreversible change. Correlation study revealed no association between patient age and histological findings, and there was no statistically significant difference in any histopathological category regardless of age. Differential renal function correlated with inflammatory cell infiltration and interstitial fibrosis. There were significantly worse histopathology scores in all categories when differential renal function was less than 30 versus 40% or greater. Interstitial fibrosis was significantly worse in the 30 to 40% group than in the greater than 40% group. The histopathological score of interstitial fibrosis was significantly higher in patients with than without urinary tract infection. Early correction in infants with ureteropelvic junction obstruction may not be necessary when initial differential renal function is greater than 40%. However, any decrease in differential renal function or recurrent urinary tract infections despite antibiotic prophylaxis warrant surgical correction of obstruction.

DOES DELAYED OPERATION FOR PEDIATRIC URETEROPELVIC JUNCTION OBSTRUCTION CAUSE HISTOPATHOLOGICAL CHANGES?

Purpose We studied histopathological changes in kidneys with demonstrable ureteropelvic junction obstruction in relation to patient age, differential renal function and urinary tract infection. Materials and Methods Renal biopsy was performed in 42 children (44 kidneys) with a mean age of 3 years 6 months who underwent open pyeloplasty due to ureteropelvic junction obstruction. Each specimen was examined for reversible inflammatory cell infiltration and irreversible change, including interstitial fibrosis, arteriolar thickening and glomerular sclerosis. Each pathological finding was scored 0 to 3 in increasing grades of severity, and correlated with patient age, differential renal function and history of urinary tract infection. Results Of the 44 kidneys 20 (45%) had irreversible change. Correlation study revealed no association between patient age and histological findings, and there was no statistically significant difference in any histopathological category regardless of age. Differential renal function correlated with inflammatory cell infiltration and interstitial fibrosis. There were significantly worse histopathology scores in all categories when differential renal function was less than 30 versus 40% or greater. Interstitial fibrosis was significantly worse in the 30 to 40% group than in the greater than 40% group. The histopathological score of interstitial fibrosis was significantly higher in patients with than without urinary tract infection. Conclusions Early correction in infants with ureteropelvic junction obstruction may not be necessary when initial differential renal function is greater than 40%. However, any decrease in differential renal function or recurrent urinary tract infections despite antibiotic prophylaxis warrant surgical correction of obstruction.