Adaptive functional change of the contralateral kidney after partial nephrectomy.

Partial nephrectomy aims to maintain renal function by nephron sparing; however, functional changes in the contralateral kidney remain unknown. We evaluate the functional change in the contralateral kidney using a diethylene triamine penta-acetic acid (DTPA) renal scan and determine factors predicting contralateral kidney function after partial nephrectomy. A total of 699 patients underwent partial nephrectomy, with a DTPA scan before and after surgery to assess the separate function of each kidney. Patients were divided into three groups according to initial contralateral glomerular filtration rate (GFR; group 1: <30 ml·min-1·1.73 m-2, group 2: 30-45 ml·min-1·1.73 m-2, and group 3: ≥45 ml·min-1·1.73 m-2). Multiple-regression analysis was used to identify the factors associated with increased GFR of the contralateral kidney over a 4-yr postoperative period. Patients in group 1 had a higher mean age and hypertension history, worse American Society of Anesthesiologists score, and larger tumor size than in the other two groups. The ipsilateral GFR changes at 4 yr after partial nephrectomy were -18.9, -3.6, and 3.9% in groups 1, 2, and 3, respectively, whereas the contralateral GFR changes were 10.8, 25.7, and 38.8%. Age [ß: -0.105, 95% confidence interval (CI): -0.213; -0.011, P < 0.05] and preoperative contralateral GFR (ß: -0.256, 95% CI: -0.332; -0.050, P < 0.01) were significant predictive factors for increased GFR of the contralateral kidney after 4 yr. The contralateral kidney compensated for the functional loss of the ipsilateral kidney. The increase of GFR in contralateral kidney is more prominent in younger patients with decreased contralateral renal function.

Can cystatin C become an easy and reliable tool for anesthesiologists to calculate glomerular filtration rate?

BACKGROUND AND AIMS: The aim was to evaluate the role of cystatin C as a noninvasive and easy marker of glomerular filtration rate (GFR) estimation in voluntary kidney donors. MATERIALS AND METHODS: We retrospectively evaluated 40 voluntary kidney donors. They underwent complete biochemical and nuclear tests as a part of transplant workup. Serum cystatin C, serum creatinine, and Tc-99m diethylene-triamine-penta-acetic acid (DTPA) were used in our study. We calculated GFR using the chronic kidney disease epidemiology collaboration (CKD-EPI) formula based on creatinine only (GFR-CKD-EPI-creat), CKD-EPI formula using creatinine and cystatin C (GFR-CKD-EPI-cyst-creat), and modification of diet in renal disease (MDRD) and CKD-EPI cystatin C equation (2012) (GFR-cyst). Data was evaluated using the SPSS software (version 11.5). The correlation analysis and analysis of variance was used for statistical computation. Agreement was determined using analyze-it version 2.30 for MS-Excel 12+. RESULTS: The mean age of the donors in our study was 49.83 ± 13.06. The mean cystatin C in females was 0.72 ± 0.12, the mean cystain C in males was 0.87 ± 0.23. On correlating GFR-cyst with GFR-DTPA the Pearson correlation coefficient (ρ) was found to be 0.388 this correlation was significant with P < 0.05. While comparing with DTPA the correlation coefficient of GFR-CKD-EPI-creat group was 0.587 which was significant with P < 0.01. The correlation coefficient of GFR-CKD-EPI-cyst-creat group compared with GFR-DTPA group was 0.543 which was also significant at P < 0.001. GFR-CKD-EPI-creat gave the highest correlation with DTPA in our study. The correlation coefficient of GFR-MDRD group with DTPA group was 0.576 this correlation was also significant with P < 0.01. The results obtained were further statistically analyzed by Bland-Altman analysis the percentage error for GFR-DTPA versus GFR-cyst-creat is 29.72%; for GFR-DTPA versus GFR-EPI-creat is 30.73%; or GFR-DTPA versus MDRD is 31.63% and for GFR-DTPA versus GFR-cyst is 34.37%. CONCLUSION: Cystatin C is a good endogenous marker for calculating GFR as it correlates very well with DTPA and CKD-EPI equation based GFR.

Combined molecular MRI and immuno-spin-trapping for in vivo detection of free radicals in orthotopic mouse GL261 gliomas.

Free radicals play a major role in gliomas. By combining immuno-spin-trapping (IST) and molecular magnetic resonance imaging (mMRI), in vivo levels of free radicals were detected within mice bearing orthotopic GL261 gliomas. The nitrone spin trap DMPO (5,5-dimethyl pyrroline N-oxide) was administered prior to injection of an anti-DMPO probe (anti-DMPO antibody covalently bound to a bovine serum albumin (BSA)-Gd (gadolinium)-DTPA (diethylene triamine penta acetic acid)-biotin MRI contrast agent) to trap tumor-associated free radicals. mMRI detected the presence of anti-DMPO adducts by either a significant sustained increase (p<0.001) in MR signal intensity or a significant decrease (p<0.001) in T1 relaxation, measured as %T1 change. In vitro assessment of the anti-DMPO probe indicated a significant decrease (p<0.0001) in T1 relaxation in GL261 cells that were oxidatively stressed with hydrogen peroxide, compared to controls. The biotin moiety of the anti-DMPO probe was targeted with fluorescently-labeled streptavidin to locate the anti-DMPO probe in excised brain tissues. As a negative control a non-specific IgG antibody covalently bound to the albumin-Gd-DTPA-biotin construct was used. DMPO adducts were also confirmed in tumor tissue from animals administered DMPO, compared to non-tumor brain tissue. GL261 gliomas were found to have significantly increased malondialdehyde (MDA) protein adducts (p<0.001) and 3-nitrotyrosine (3-NT) (p<0.05) compared to normal mouse brain tissue, indicating increased oxidized lipids and proteins, respectively. Co-localization of the anti-DMPO probe with either 3-NT or 4-hydroxynonenal was also observed. This is the first report regarding the detection of in vivo levels of free radicals from a glioma model.

Comparison between Three Techniques for Determining Glomerular Filtration Rates: 99mTc-Diethylene Triamine Penta-Acetic Acid Renography, Double Plasma Sampling Method, and Single Plasma Sampling Method in Vietnamese Patients.

Glomerular filtration rate (GFR) is an important indicator of renal function. Many methods have been developed to determine GFR in clinical examinations. This study aims to correlate between radionuclide plasma sampling methods (single and double blood samples, in vitro methods) and in vivo Gate's method using 99mTc-diethylene triamine penta-acetic acid (99mTc-DTPA) renography. MATERIALS AND METHODS: 43 patients underwent this study, including 31 renal donors (Group 1) and 12 patients with obstructive uropathy (Group 2). All patients were administered with a range of 5-7 mCi of 99mTc-DTPA. Then, renography performed simultaneously after injection and GFR calculation followed by Gate's method. Blood samples were collected at 60- and 120-min postinjection, samples were counted by a thyroid uptake system, and GFR was calculated using a single plasma sample method (SPSM) and a double plasma sample method (DPSM). RESULTS: The mean GFRs calculated by Gate's method in Groups 1 and 2 were 85.8 ± 18.2 ml/min and 118.4 ± 13.9 ml/min, respectively. Meanwhile, using the in vitro blood sampling methods (DPSM and SPSM), the mean GFRs in Group 1 were 73.8 ± 15.4 ml/min and 56.4 ± 20.9 ml/min, respectively, and in Group 2 were 116.8 ± 12.9 ml/min and 106.3 ± 18.5 ml/min, respectively. There is a high correlation between Gate's method and DPSM in two groups (r = 0.86 and 0.72, respectively), and a moderate correlation was found between Gate's method and SPSM in both groups (r = 0.49 and r = 0.37, respectively). The two in vitro methods (DPSM and SPSM) revealed that moderate correlation in both groups (r = 0.74 and r = 0.67, respectively) was observed. CONCLUSION: Renography is a simple method but considered inaccurate for GFR determination. However, in vitro plasma sampling is rarely used in Vietnam. In this study, Gate's method correlated well with DPSM and tended to overestimate GFR. Further, the in vitro methods can be applied to correct the in vivo method as a confirmatory test in some cases.

Role of calculated glomerular filtration rate using percutaneous nephrostomy creatinine clearance in the era of radionuclide scintigraphy.

CONTEXT: Gates method tends to over-estimate glomerular filtration rate (GFR) in borderline functioning kidneys. We study the role of calculated GFR in these cases in decision-making regarding performing kidney-sparing surgery or nephrectomy. AIMS: The aim of this study is to find the correlation between GFR calculated by percutaneous nephrostomy (PCN) urine creatinine clearance in obstructed kidneys and GFR by radionuclide scintigraphy. It also studies the role of this calculated GFR in borderline functioning kidneys. SETTINGS AND DESIGN: Single tertiary care center; retrospective. MATERIALS AND METHODS: A total of 46 patients in whom PCN was inserted as an emergency measure in an obstructed kidney and for whom diethylene-triamine-penta-acetic acid/ethylene-di-cysteine (DTPA/EC) scan was also done (Gates method) were analyzed retrospectively. PCN creatinine clearance was calculated for 3 consecutive days, and the mean value was used. STATISTICAL ANALYSIS USED: Pearson's correlational analysis; Chi-square test. RESULTS: Overall strong correlation was found between the two GFR values (Pearson's r = 0.540692, P < 0.001). Totally 26 patients (56.52%) had comparable GFR values (P > 0.05). Among the 36 patients with borderline functioning kidneys, DTPA/EC scan significantly over-estimated GFR in one-third of the patients. The management plan was changed in 7 out of those patients (46.67%), with nephrectomy performed in all instead of kidney-sparing procedure. When the highest value of calculated GFR was compared, 28 patients had comparable GFRs (60.87%). CONCLUSIONS: GFR based on radionuclide scintigraphy may be insufficient for evaluation of residual renal function to determine the management of obstructed kidney with borderline function. For adequate decision-making, other factors including creatinine clearance via PCN should also be considered. Gates method tends to overestimate GFR as compared to calculated creatinine clearance at low GFR levels.

Use of fibrin glue as a sealant at the anastomotic line in laparoscopic pyeloplasty: A randomised controlled trial.

OBJECTIVE: To assess the effectiveness of fibrin glue as a sealant at the anastomotic line of a stentless laparoscopic pyeloplasty (LPP) repair instead of JJ stent insertion. PATIENTS AND METHODS: In all, 46 patients with pelvi-ureteric junction obstruction scheduled for LPP were randomised into two groups each containing 23 patients. Group A underwent stented repair, while group B had a stentless repair together with sealing of the anastomotic line with fibrin glue. RESULTS: There was no statistically significant difference between the groups for the postoperative improvement in the renal scan and intravenous urography. However, there was a statistically significant decrease in early postoperative adverse events in group B. In group A, all the patients had irritative lower urinary tract symptoms (LUTS) and 16 (72.7%) had postoperative urinary tract infections (UTIs). In group B, no patient had a UTI or irritative LUTS. In all, 21 patients (95.4%) in group A had minimal terminal painful haematuria; while in group B, only one patient (4.3%) had minimal total painless haematuria. Also, patients in group B were spared the need for a second anaesthesia exposure for stent removal. CONCLUSION: The use of fibrin glue is a valid alternative to stenting in LPP with the same excellent outcome but with markedly lower short-term postoperative adverse events.

The embedded nipple: An optimal technique for re-implantation of primary obstructed megaureter in children.

OBJECTIVES: To present a novel ureteric re-implantation technique for primary obstructed megaureter (POM) that ensures success in the short- and long-term, as conventional techniques are not ideal for megaureters especially in children, with ureteric stenosis and reflux being common complications after re-implantation. PATIENTS AND METHODS: Between 2009 and 2012, 22 paediatric patients with POM were enrolled. We performed a new technique for re-implantation of these ureters to ensure minimal incidence of ureteric strictures and easy subsequent endoscopic access. We performed follow-up voiding cystourethrography (VCUG) at 6 months postoperatively. RESULTS: The cohort comprised 14 boys and eight girls, with a median age of 22 months. Six patients underwent bilateral re-implantation. The mean (range) duration of indwelling ureteric catheterisation was 7.8 (4-14) days. There were no complications in the perioperative and postoperative periods. There was no reflux on follow-up VCUG in any of the patients. One patient developed Grade I reflux after 1 year and presented with a urinary tract infection. Diagnostic cystoscopy was performed in 13 patients showing that the nipple was directed similarly to the native ureteric orifice. CONCLUSION: The embedded-nipple technique for re-implantation of POM guarantees successful results and permits easy subsequent ureteroscopic access when needed.

Modification of diet in renal disease and Cockraft-Gaultformula accuracy in glomerular filtration rate estimation in Iranian adults.

INTRODUCTION: The aim of this study was to evaluate the accuracy of modification of diet in renal disease (MDRD) and Cockraft-Gault (C-G) formulas for estimating GFR in a sample of Iranian adult. MATERIALS AND METHODS: This study was an analytic cross-sectional study on 54 patients with chronic kidney disease. Glomerular filtration rate was measured by kidney scan via TC99m-labeled diethylenetriaminepentaacetic acid, and it was estimated by MDRD and Cockraft-Gault formulas. RESULTS: The mean of measured GFR and estimated GFR by MDRD and C-G formulas was 61.64 ± 34.26 ml/min, 51.80 ± 25.47, and 54.29 ± 24 ml/min respectively (P-value < 0.001, r = 0.818 and P-value < 0.001, r = 0.847, respectively). Pearson correlation test showed direct linear relationship between sGFR and GFR as estimated by the Cockraft-Gault and MDRD formulas. CONCLUSION: Based on our results, modification of diet in renal disease (MDRD) and Cockraf-Gault (C-G) formulas are accurate formulas in Iranian adults but they need a correction factor.