Compare serum creatinine versus Renal 99mTc-DTPA scan determined glomerular filtration rates in veterans with traumatic spinal cord injury and meurogenic bladder

Follow-up for the upper urinary tract in patients with high-risk neurogenic lower urinary tract dysfunction

PURPOSE

Patients with neurogenic lower urinary tract dysfunction (nLUTD) can be at risk of preventable damage to the upper urinary tract (UUT), a risk that varies with the underlying diagnosis. Existing literature fails to document precisely which domains of UUT must be followed. This review focusses on surveillance of UUT with special emphasis on high-risk nLUTD.

METHODS

Narrative review of available evidence and current global guidelines to identify patients of nLUTD at higher risk of UUT damage and to define each domain that needs to be followed.

RESULTS

Patients with open spina bifida, spinal cord injury, and anorectal malformation, as well as those with unsafe features on clinical evaluation or urodynamics should be considered at high risk. Structured program should include evaluation of (1) glomerular filtration rate (GFR) which can be estimated ± measured, (2) renal growth (in pre-pubertal children) by ultrasonography, (3) renal scarring by baseline nuclear renogram, (4) hydronephrosis and stones by ultrasonography, (5) vesicoureteral reflux by baseline video-urodynamics, (6) non-GFR measures of renal function (somatic growth, hypertension, proteinuria, anemia and metabolic acidemia). Serum creatinine-based estimations of GFR are more likely to be confounded in select patients with high-risk nLUTD than cystatin-based estimations and measured-GFR. Urological guidelines do not always describe details of UUT surveillance and appear to lack cognizance of nephrology guidelines for evaluation of kidneys.

CONCLUSION

A structured surveillance protocol that includes clear documentation of each domain of the UUT is important in ensuring optimum care for patients with high-risk nLUTD.

Feasibility of 24-h urine creatinine clearance as a renal function monitoring tool in spinal cord injury patients

OBJECTIVE

Renal dysfunction is a major cause of morbidity in patients with spinal cord injury (SCI). A 24-h urine creatinine (Cr) clearance (24-h urine CCr) is cost-effective and easy to implement compared to renal scintigraphy in the evaluation of renal function. This study aimed to verify the feasibility of 24-h urine CCr in the SCI population by assessing the correlation with effective renal plasma flow (ERPF) on renal scintigraphy.

METHODS

Data from 245 SCI patients (189 males, mean age: 50.2 years) were used in this retrospective review. Clinical characteristics, 24-h urine CCr, serum Cr, comorbidities, and body composition analyses were assessed for correlation with laboratory parameters including renal scintigraphy. Strong predictors of ERPF were determined by multivariate linear regression analysis. Areas under receiver-operating characteristic curves were calculated to evaluate the discriminating power of 24-h urine CCr to predict ERPF <250 ml/min.

RESULTS

Spinal cord injury patients showed tubular dysfunction despite normal serum Cr and 24-h urine CCr. There was a significant correlation between 24-h urine CCr and ERPF, and 24-h urine CCr was one of the strongest predictors for ERPF (area under the curve 0.72, 95% CI 0.64-0.80, p < 0.000) among other parameters such as age, appendicular lean mass index, and body mass index. 24-h urine CCr was an independent predictor of ERPF in subacute (R²  = 0.497, p < 0.001) and chronic SCI patients (R²  = 0.664, p < 0.0001). The optimized 24-h urine CCr cut-off was 139.4 ml/min/1.72 m² for predicting decreased ERPF <250 ml/min (sensitivity 67.6% and specificity 64.0%).

CONCLUSION

24-h urine CCr is a sensitive indicator for renal function deterioration of SCI patients. Further longitudinal studies with larger numbers of SCI patients are needed to confirm the feasibility of 24-h urine CCr for monitoring this population.

Comparative Analysis of Trifecta Outcomes in Robot-Assisted Partial Nephrectomy for cT1a Versus cT1b + Renal Tumours-a Single-Centre Study

Robotic assistance is being increasingly utilised for nephron-sparing surgery for complex renal masses. We evaluated the outcomes of robot-assisted partial nephrectomy (RAPN) for cT1a versus cT1b + renal masses by a comparative analysis of trifecta outcomes between these two groups of patients. We utilised our prospectively maintained database to identify patients undergoing RAPN for cT1a (group 1, n = 41) and cT1b + (group 2, n = 37) renal masses from April 2016 to March 2020. The oncological and trifecta outcomes were analysed using appropriate statistical methods. Out of 78 patients, trifecta was achieved in 30 (38.4%) patients. There was no statistically significant difference in trifecta between cT1a and cT1b + tumours (p = 0.152). We found a statistically significant difference between the two groups in terms of RENAL scores (p = 0.0005), PADUA score (p = 0.0002), and robotic console time (133.8 ± 42.8 Vs 170 ± 54.8 min for cT1a versus cT1b + , respectively) (p = 0.002). On multivariate analysis, warm ischemia time (p = 0.069), blood loss (p = 0.345), UCS repair (p = 0.691) and GFR reduction (p = 0.152) were not statistically different. There was no statistically significant difference in intraoperative and post-operative complications (p = 0.9317) or length of hospital stay (p = 0.112). Although recurrences were observed in two patients (5.4%) of the cT1b group, there was no statistical difference in the recurrence-free survival at 12 and 24 months. Our study shows that RAPN can be safely done for cT1b + renal tumours. These findings reinforce the view that RAPN should be considered a viable option for cT1b + lesions whenever technically feasible.

Endocrinological and inflammatory markers in individuals with spinal cord injury: A systematic review and meta-analysis

Spinal cord injury (SCI) can lead to dramatic physiological changes which can be a factor in developing secondary health conditions and might be reflected in biomarker changes in this elevated risk group. We focused specifically on the endocrine and inflammation profile differences between SCI and able-bodied individuals (ABI). Our aim was to determine the differences in inflammatory markers and endocrine profiles between SCI and ABI. We systematically searched 4 electronic databases for relevant studies. Human observational (cross-sectional, cohort, case-control) studies that compared biomarkers of interest between SCI and ABI population were included. Weighted mean difference between SCI and ABI was calculated using random-effects models. Heterogeneity was computed using I² statistic and chi-squared test. Study quality was evaluated through the Newcastle-Ottawa Scale. The search strategy yielded a total of 2,603 studies from which 256 articles were selected for full-text assessment. Sixty-two studies were included in the meta-analysis. SCI individuals had higher levels of pro-inflammatory C-reactive protein and IL-6 than ABI. Creatinine and 25-hydroxyvitamin D₃ levels were lower in SCI than ABI. Total testosterone levels and IGF-1 were also found to be lower, while cortisol and leptin levels were higher in SCI when compared to ABI. Accordingly, meta-regression, subgroup analysis, and leave-one-out analysis were performed, however, they were only able to partially explain the high levels of heterogeneity. Individuals with SCI show higher levels of inflammatory markers and present significant endocrinological changes when compared to ABI. Moreover, higher incidence of obesity, diabetes, osteoporosis, and hypogonadism in SCI individuals, together with decreased creatinine levels reflect some of the readily measurable aspects of the phenotype changes in the SCI group. These findings need to be considered in anticipating medically related complications and personalizing SCI medical care.

Glomerular Filtration Rate Estimation With Commonly Used Methods Among Healthy Live Kidney Donors of South Punjab, Pakistan

Background

Accurate estimation of the donor’s glomerular filtration rate (GFR) is crucial for not only ensuring the medical appropriateness of the donor but also for the prediction of future allograft performance. The aim of this study was to compare the GFR estimation formulas and 24-hour urine creatinine clearance with diethylene triamine pentaacetic acid (DTPA) renal scan GFR.

Methods

This cross-sectional study was done at the Department of Nephro Urology Dialysis & Renal Transplantation, Bahawal Victoria Hospital, Quaid e Azam Medical College, Bahawalpur, Pakistan from September 2018 to September 2021. A total of 92 potential healthy live-related kidney donors of both genders, aged 18 to 60 years having body mass index below 35 kg/m² were included. GFR was calculated with modification of diet in renal disease (MDRD), Cockcroft-Gault (CG), chronic kidney disease epidemiology (CKD-EPI) equations as well as by 24-hour urine creatinine clearance. DTPA renal scan was done to record GFR findings. GFR was compared using analysis of variance (ANOVA) among different methods.

Results

Out of a total of 92 individuals, 49 (53.3%) were male and 43 (46.7%) female. Mean age and BMI were noted to be 34.62±10.57 years and 24.40±2.71 kg/m², respectively. Statistically significant differences existed between various methods of GFR estimation (p<0.001). Mean GFR as per DTPA renal scan findings was noted to be 97.32±9.39 ml/min/1.73 m². Difference of 31.48±20.81, 27.37±21.1, 23.38±6.38, 15.52±37.52 was noted in estimated GFR (ml/min/1.73 m²) with CG formula, MDRD formula, EPI-CKD formula and 24-hour urine creatinine clearance respectively when compared with DTPA renal scan findings. The highest proportion of patients was seen with normal GFR with DTPA renal scan findings as 83 (90.2%) individuals while 24-hour urine creatinine clearance observed these to be 59 (64.1%), CG EPI-CKD formula 44 (47.8%), MDRD formula 39 (42.4%) and 40 (43.5%) with CG formula.

Conclusion

None of the GFR estimation methods resulted in similar findings. With reference to the DTPA renal scan, 24-hour urine creatinine clearance was the closest GFR estimation followed by CKD-EPI and MDRD equations.

Prospective comparison between DCE-MRR and 99m Tc-DTPA-based SPECT for determination of allograft renal function

BACKGROUND

Glomerular filtration rate (GFR) is a preferred indicator of allograft renal function, but direct measurement of GFR remains complicated.

PURPOSE

To prospectively compare dynamic contrast-enhanced MR renography (DCE-MRR) with ^99m Tc-DTPA-based single-photon emission computed tomography (SPECT) for determination of allograft renal function.

STUDY TYPE

Prospective.

POPULATION

Seventy kidney-transplant recipients FIELD STRENGTH: A low-dose DCE-MRR with a 3.0T scanner and a ^99m Tc-DTPA-based SPECT after renal transplantation were performed.

ASSESSMENT

A Baumann-Rudin (BR) and a modified two-compartment model (JZ2C) were used for DCE-MRR analysis. Standard Gate's method was used for SPECT analysis. An endogenous creatinine clearance rate (CCr) constituted the reference standard.

STATISTICAL TESTS

Pearson correlation test and Bland-Altman agreement analysis.

RESULTS

The reference CCr-GFR was 59.58 ± 23.72 mL/min/1.73 m² . GFR determined by eGFR, BR, JZ2C, and SPECT was 90.22 ± 34.38, 36.78 ± 14.46, 48.99 ± 23.88, and 67.32 ± 18.44 mL/min/1.73 m² , respectively. DCE-MRR using JZ2C had the best overall performance, with a Pearson correlation coefficient of 0.81, a bias of -10.58 mL/min/1.73 m² , and a precision of 14.61 mL/min/1.73 m² , as well as high accuracy (30-50% intervals: 74.3-90.0%). Although SPECT had a small bias (7.74 mL/min/1.73 m² ), it had a poor correlation coefficient (0.38), poor precision (23.93 mL/min/1.73 m² ), and low accuracy (64.3-72.3%) as compared with DCE-MRR using JZ2C.

DATA CONCLUSION

DCE-MRR using JZ2C is superior to ^99m Tc-DTPA-based SPECT to determine allograft renal function.

LEVEL OF EVIDENCE

2 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2019;49:262-269.