The CKD-EPI equation for estimating GFR from serum creatinine: real improvement or more of the same?

Glomerular filtration rate is an independent prognostic factor in patients with B-large cell lymphoma

Chronic kidney dysfunction is associated with increased mortality in multiple cancer types. Preliminary evidence suggests the same to be true for B-large cell lymphomas (B-LCL). To analyze the relationship of glomerular filtration rate (GFR) and outcome of B-LCL in detail we collected data on outcomes of 285 consecutive patients with newly diagnosed B-LCL treated at our institution with standard rituximab-containing regimens who did not have preexisting kidney disease or urinary tract obstruction at presentation. Median age was 59, range 18 to 87, 145 were male and 140 females. Forty-four had GFR < 60 mL/min, 123 had 60 to 90 mL/min, and 118 > 90 mL/min. Median follow-up of surviving patients was 49 months and estimated 3-year survival 76%. In univariate analysis age (P < .001), GFR (P = .014), stage (P < .001), performance status (P = .044), chemotherapy regimen (P < .01), and international prognostic index (IPI) (P < .001) were statistically significant prognostic factors. In multivariate analysis, age and GFR remained the only independent prognostic factors. Subtracting 1 from the IPI score of patients who had GFR > 90 mL/min and IPI > 1 resulted in a prognostic index that divides patients into 3 prognostic groups (low risk = 0-1, intermediate risk = 2-3 and high risk = 4-5) with an acceptable patient distribution frequency (38%, 39%, and 23%, respectively) and improved statistical significance and separation in comparison to IPI (5-year survival rates of 92%, 74%, and 42%, respectively). GFR is an important independent prognostic factor for B-LCL that should be taken into account in clinical decision making and data analysis and probably be incorporated in prognostic indices.

Intraoperative mean arterial pressure and acute kidney injury after robot-assisted laparoscopic prostatectomy: a retrospective study

Intraoperative hemodynamics can affect postoperative kidney function. We aimed to investigate the effect of intraoperative mean arterial pressure (MAP) as well as other risk factors on the occurrence of acute kidney injury (AKI) after robot-assisted laparoscopic prostatectomy (RALP). We retrospectively evaluated the medical records of 750 patients who underwent RALP. The average real variability (ARV)-MAP, standard deviation (SD)-MAP, time-weighted average (TWA)-MAP, area under threshold (AUT)-65 mmHg, and area above threshold (AAT)-120 mmHg were calculated using MAPs collected within a 10-s interval. Eighteen (2.4%) patients developed postoperative AKI. There were some univariable associations between TWA-MAP, AUT-65 mmHg, and AKI occurrence; however, multivariable analysis found no association. Alternatively, American Society of Anesthesiologists physical status ≥ III and the low intraoperative urine output were independently associated with AKI occurrence. Moreover, none of the five MAP parameters could predict postoperative AKI, with the area under the receiver operating characteristic curve values for ARV-MAP, SD-MAP, TWA-MAP, AUT-65 mmHg, and AAT-120 mmHg being 0.561 (95% confidence interval [CI], 0.424-0.697), 0.561 (95% CI, 0.417-0.704), 0.584 (95% CI, 0.458-0.709), 0.590 (95% CI, 0.462-0.718), and 0.626 (95% CI, 0.499-0.753), respectively. Therefore, intraoperative MAP changes may not be a determining factor for AKI after RALP.

The Predictive Value of Donor Renal Functions, Graft Weight, Recipient Body Mass Index, and Human Leucocyte Antigen Match Regarding Early Graft Functions

Background and objective Graft performance is the most important postoperative parameter for patients undergoing kidney transplantation (KTx). The renal function of the donor is reported to be correlated with graft function after KTx. The body mass index (BMI) is also one of the important parameters involved in the prediction of graft function. The aim of this retrospective study was to examine the relationship between early postoperative graft function in patients undergoing KTx and donor cystatin C and estimated glomerular filtration rate (e-GFR) levels, graft weight/recipient BMI (G/B) ratio, and human leukocyte antigen (HLA) tissue compatibility. Materials and methods A total of 215 cases (215 donors, 215 recipients) who underwent KTx at our center between January 2018 and December 2022 were included in the study. Patients' age, sex, BMI, preoperative donor serum cystatin C and e-GFR levels, HLA tissue compatibility, graft weights, and recipient creatinine levels were recorded one week postoperatively. The Kolmogorov-Smirnov test and histogram plots were used to analyze the conformity of the variables to the normal distribution and Spearman's correlation test was used to analyze the relationship between variables. Results A negative correlation was identified between recipient creatinine level and G/B ratio and donor e-GFR (r = -0.256 and -0.137, respectively). Donor cystatin C level showed a positive correlation with recipient creatinine level (r = 0.242). No significant correlation was noted in terms of tissue matching rates (p = 0.616). Conclusion Although these three parameters are correlated with early graft functions, the graft weight/recipient BMI ratio has the strongest correlation.

Association between 20% Albumin Use and Acute Kidney Injury in Major Abdominal Surgery with Transfusion

Red blood cell (RBC) transfusion and albumin administration can affect kidney function. We aimed to evaluate the association between intraoperative 20% albumin administration and acute kidney injury (AKI), along with the duration of hospitalization and 30-day mortality in patients undergoing major abdominal surgery with RBC transfusion. This retrospective study included 2408 patients who received transfusions during major abdominal surgery. Patients were categorized into albumin (n = 842) or no-albumin (n = 1566) groups. We applied inverse probability of treatment weighting (IPTW), propensity score (PS) matching (PSM), and PS covariate adjustment to assess the effect of albumin administration on the outcomes. In the unadjusted cohort, albumin administration was significantly associated with increased risk of AKI, prolonged hospitalization, and higher 30-day mortality. However, there was no significant association between albumin administration and AKI after adjustment (OR 1.26, 95% CI 0.90-1.76 for the IPTW; OR 1.03, 95% CI 0.72-1.48 for the PSM; and OR 1.04, 95% CI 0.76-1.43 for the PS covariate adjustment methods). While albumin exposure remained associated with prolonged hospitalization after adjustment, it did not affect 30-day mortality. Our findings suggest that hyper-oncotic albumin can be safely administered to patients who are at risk of developing AKI due to RBC transfusion.

A risk scoring system integrating postoperative factors for predicting early mortality after major non-cardiac surgery

We aimed to develop a risk scoring system for 1-week and 1-month mortality after major non-cardiac surgery, and assess the impact of postoperative factors on 1-week and 1-month mortality using machine learning algorithms. We retrospectively reviewed the medical records of 21,510 patients who were transfused with red blood cells during non-cardiac surgery and collected pre-, intra-, and postoperative features. We derived two patient cohorts to predict 1-week and 1-month mortality and randomly split each of them into training and test cohorts at a ratio of 8:2. All the modeling steps were carried out solely based on the training cohorts, whereas the test cohorts were reserved for the evaluation of predictive performance. Incorporation of postoperative information demonstrated no significant benefit in predicting 1-week mortality but led to substantial improvement in predicting 1-month mortality. Risk scores predicting 1-week and 1-month mortality were associated with area under receiver operating characteristic curves of 84.58% and 90.66%, respectively. Brain surgery, amount of intraoperative red blood cell transfusion, preoperative platelet count, preoperative serum albumin, and American Society of Anesthesiologists physical status were included in the risk score predicting 1-week mortality. Postoperative day (POD) 5 (neutrophil count × mean platelet volume) to (lymphocyte count × platelet count) ratio, preoperative and POD 5 serum albumin, and occurrence of acute kidney injury were included in the risk score predicting 1-month mortality. Our scoring system advocates the importance of postoperative complete blood count differential and serum albumin to better predict mortality beyond the first week post-surgery.

Predictive models for chronic kidney disease after radical or partial nephrectomy in renal cell cancer using early postoperative serum creatinine levels

Background

Several predictive factors for chronic kidney disease (CKD) following radical nephrectomy (RN) or partial nephrectomy (PN) have been identified. However, early postoperative laboratory values were infrequently considered as potential predictors. Therefore, this study aimed to develop predictive models for CKD 1 year after RN or PN using early postoperative laboratory values, including serum creatinine (SCr) levels, in addition to preoperative and intraoperative factors. Moreover, the optimal SCr sampling time point for the best prediction of CKD was determined.

Methods

Data were retrospectively collected from patients with renal cell cancer who underwent laparoscopic or robotic RN (n = 557) or PN (n = 999). Preoperative, intraoperative, and postoperative factors, including laboratory values, were incorporated during model development. We developed 8 final models using information collected at different time points (preoperative, postoperative day [POD] 0 to 5, and postoperative 1 month). Lastly, we combined all possible subsets of the developed models to generate 120 meta-models. Furthermore, we built a web application to facilitate the implementation of the model.

Results

The magnitude of postoperative elevation of SCr and history of CKD were the most important predictors for CKD at 1 year, followed by RN (compared to PN) and older age. Among the final models, the model using features of POD 4 showed the best performance for correctly predicting the stages of CKD at 1 year compared to other models (accuracy: 79% of POD 4 model versus 75% of POD 0 model, 76% of POD 1 model, 77% of POD 2 model, 78% of POD 3 model, 76% of POD 5 model, and 73% in postoperative 1 month model). Therefore, POD 4 may be the optimal sampling time point for postoperative SCr. A web application is hosted at https://dongy.shinyapps.io/aki_ckd.

Conclusions

Our predictive model, which incorporated postoperative laboratory values, especially SCr levels, in addition to preoperative and intraoperative factors, effectively predicted the occurrence of CKD 1 year after RN or PN and may be helpful for comprehensive management planning.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12967-021-02976-2.

Chronic kidney disease and cardiovascular mortality in patients with atrial fibrillation: European Society of Hypertension project - ESH A Fib

Our aim was to analyze characteristics of atrial fibrillation (AF) patients with chronic kidney disease (CKD) from the Croatian cohort of the ESH A Fib survey and to determine the association of estimated glomerular filtration rate (eGFR) with cardiovascular (CV) mortality after 24 months of follow-up.Consecutive sample of 301 patients with AF were enrolled in the period 2014 to 2018. Hypertension was defined as BP > 140/90 mm Hg and/or antihypertensive drugs treatment, CKD was defined as eGFR (CKD Epi) < 60 ml/min/1.73 m2 which was confirmed after 3 months.CKD was diagnosed in 45.2% of patients (13.3% in CKD stage > 3b). CKD patients were older than non-CKD and had significantly more frequent coronary heart disease, heart failure and valvular disease. CKD patients had significantly higher CHA2DS2-VASc score and more CKD than non-CKD patients had CHA2DS2-VASc > 2. Crude CV mortality rate per 1000 population at the end of the first year of the follow-up was significantly higher in CKD vs non-CKD group who had shorter mean survival time. CV mortality was independently associated with eGFR, male gender, CHA2DS2VASc and R2CHA2DS2VASc scores.Prevalence of CKD, particularly more advanced stages of CKD, is very high in patients with AF. Observed higher CV mortality and shorter mean survival time in CKD patients could be explained with higher CHA2DS2VASc score which is a consequence of clustering of all score components in CKD patients. However, eGFR was independently associated with CV mortality. In our cohort, R2CHA2DS2VASc score was not associated significantly more with CV mortality than CHA2DS2VASc score.

Comparison of high glomerular filtration rate thresholds for identifying hyperfiltration

BACKGROUND

High glomerular filtration rate (GFR) is often used as a surrogate for single-nephron hyperfiltration. Our objective was to determine the definition for high GFR that best reflects clinical and structural characteristics of hyperfiltration.

METHODS

We studied living kidney donors at the Mayo Clinic and Cleveland Clinic. Potential donors underwent evaluations that included measured GFR (mGFR) by iothalamate clearance and estimated GFR (eGFR) by the serum creatinine-based Chronic Kidney Disease-Epidemiology collaboration (CKD-EPI) equation. High GFR was defined by the 95th percentile for each method (mGFR or eGFR) using either overall or age-specific thresholds. High mGFR was defined as both corrected and uncorrected for body surface area. The association of high GFR by each definition with clinical characteristics and radiologic findings (kidney volume) was assessed. In the subset that donated, the association of high GFR with kidney biopsy findings (nephron number and glomerular volume) and single-nephron GFR was assessed.

RESULTS

We studied 3317 potential donors, including 2125 actual donors. The overall 95th percentile for corrected mGFR was 134 mL/min/1.73 m2 and for eGFR was 118 mL/min/1.73 m2. The age-based threshold for uncorrected mGFR was 198 mL/min - 0.943×Age, for corrected mGFR it was 164 mL/min/1.73 m2 - 0.730×Age and for eGFR it was 146 mL/min/1.73 m2 - 0.813×Age. High age-based uncorrected mGFR had the strongest associations with higher single-nephron GFR, larger glomerular volume, larger kidney volume, male gender, higher body mass index and higher 24-h urine albumin, but also had the strongest association with high nephron number. A high age-height-gender-based uncorrected mGFR definition performed almost as well but had a weaker association with nephron number and did not associate with male gender.

CONCLUSIONS

High age-based uncorrected mGFR showed the most consistent associations reflective of hyperfiltration. However, high age-based uncorrected mGFR has limited clinical utility because it does not distinguish between hyperfiltration and high nephron number.

Prospects for improved glomerular filtration rate estimation based on creatinine-results from a transnational multicentre study

BACKGROUND

The Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) creatinine equation is routinely used to assess renal function but exhibits varying accuracy depending on patient characteristics and clinical presentation. The overall aim of the present study was to assess if and to what extent glomerular filtration rate (GFR) estimation based on creatinine can be improved.

METHODS

In a cross-sectional analysis covering the years 2003-17, CKD-EPI was validated against measured GFR (mGFR; using various tracer methods) in patients with high likelihood of chronic kidney disease (CKD; five CKD cohorts, n = 8365) and in patients with low likelihood of CKD (six community cohorts, n = 6759). Comparisons were made with the Lund-Malmö revised equation (LMR) and the Full Age Spectrum equation.

RESULTS

7In patients aged 18-39 years old, CKD-EPI overestimated GFR with 5.0-16 mL/min/1.73 m2 in median in both cohort types at mGFR levels <120 mL/min/1.73 m2. LMR had greater accuracy than CKD-EPI in the CKD cohorts (P30, the percentage of estimated GFR within 30% of mGFR, 83.5% versus 76.6%). CKD-EPI was generally the most accurate equation in the community cohorts, but all three equations reached P30 above the Kidney Disease Outcomes Quality Initiative benchmark of 90%.

CONCLUSIONS

None of the evaluated equations made optimal use of available data. Prospects for improved GFR estimation procedures based on creatinine exist, particularly in young adults and in settings where patients with suspected or manifest CKD are investigated.

Estimated Glomerular Filtration Rate as a Risk Stratification Tool for Early Complications in Revision Total Hip and Knee Arthroplasty

BACKGROUND

Establishing an association between postoperative outcomes and the spectrum of renal function would allow for more informed decisions to manage surgical risks and improved patient-specific care. Estimated glomerular filtration rate (eGFR) can be calculated from standard prescreening measurements to gauge renal function. This work investigates the effect of eGFR, as a continuous and categorical variable, on mortality and major and minor complications in patients undergoing revision total knee and hip arthroplasty.

METHODS

25,056 patients having undergone revision total hip and knee arthroplasty from 2013 to 2016 were identified using the National Quality Improvement Program database. The investigated outcomes included 30-day mortality, major complications, and minor complications. Multivariate regression models were created to evaluate the effect of eGFR on the outcomes of interest. Multivariate spline regressions were generated to assess for nonlinear relationships between eGFR as a continuous variable and the outcomes.

RESULTS

Our study revealed that as eGFR decreased <60 mL/min/1.73 m², mortality (P = .0001), any major complication (P < .001), and any minor complication (P < .001) increased. Patients with eGFR 15-30 mL/min/1.73 m² had increased risk for mortality (P = .033). There was an increased risk for any major complication at an eGFR 30-60 and <15 mL/min/1.73 m², (P < .05). There was an increased risk of minor complications for those with hyperfiltration and <60 mL/min/1.73 m².

CONCLUSION

Patients with lower preoperative eGFR generally display an increased risk for complications after revision total hip and knee arthroplasty. Proper consideration should be given to this patient population before surgical intervention to allow for preventative measures to be taken to improve patient outcomes.

Acute Kidney Injury after CAR-T Cell Therapy: Low Incidence and Rapid Recovery

Chimeric antigen receptor (CAR) T cell therapy using engineered cytotoxic T cells has shown promising responses in various hematologic malignancies. Cytokine release syndrome (CRS) and immune effector cell-associated neurologic syndrome (ICANS) are recognized toxicities of CAR-T, whereas kidney injury remains less well recognized. The objective of the present study was to identify the incidence of acute kidney injury (AKI) after CAR-T cell therapy, potential risk factors, and recovery of kidney function. We performed a retrospective review of 46 adult patients with non-Hodgkin lymphoma treated with CAR-T therapy between February 2018 and February 2019 at our institution. Serum creatinine values before CAR-T therapy through day 100 were used to assess AKI, as defined by the Kidney Disease Improving Global Outcomes (KDIGO) criteria: grade 1, 1.5- to <2-fold of baseline; grade 2, 2- to <3-fold of baseline; grade 3, ≥3-fold of baseline. CRS and ICANS were graded using the consensus criteria of the American Society of Transplantation and Cellular Therapy. The overall incidence of CRS was 78.3% (95% confidence interval [CI], 66% to 90.5%), of whom 13% (95% CI, 3.3% to 22.8%) developed grade 3-4 CRS, whereas the overall incidence of ICANS was lower at 45.7% (95% CI, 3.1% to 60.3%). The cumulative incidence of any grade AKI by day 100 was 30% (95% CI, 16.9% to 43.9%), with a grade 1 AKI incidence of 21.7% (95% CI, 9.7% to 33.8%) and a grade 2-3 AKI incidence of 8.7% (95% CI, .4% to 17%). No patients developed severe AKI necessitating renal replacement therapy. Patients with previous autologous or allogeneic stem cell transplantation, those requiring intensive care unit level care and with grade 3-4 CRS had a higher incidence of AKI. Most patients recovered, with kidney function returning to baseline within 30 days. We conclude that with early recognition and management of CAR-T complications, the incidence of AKI is low, the severity of injury is mild, and most patients recover kidney function within 30 days.

Lower number of plasma exchange sessions and glomerular filtration rate decline are associated with second relapses in patients with myasthenia gravis

The aims were to determine the impact of dysphagia and glomerular filtration rate (GFR) in the prediction of myasthenia relapse and analyse whether different number of plasma exchange sessions could prolong the time before future relapse.This was a retrospective, longitudinal follow-up study with 60 enrolled patients. The patients were followed-up for a total of 50 months.Patients without relapses had significantly higher GFR and higher number of plasma exchange sessions when compared to patients with relapses. Mean time before next myasthenia relapse was significantly longer in patients with GFR ≥ 60 mL/min. Time before next and number of following myasthenia relapses were significantly higher in patients with symptoms of dysphagia.Decline in GFR levels is strongly associated with the presence of dysphagia and independently impacts the onset of myasthenia relapses. Timely initiation of plasmapheresis therapy and adequate hydration of patients with prolonged dysphagia should be one of the treatment goals for clinicians treating this disease.

Incidence and Risk Factors for Acute and Chronic Kidney Injury after Adult Cord Blood Transplantation

Although cord blood transplantation (CBT) extends allograft access, patient comorbidities, chemoradiation, and nephrotoxic medications all contribute to acute kidney injury (AKI) risk. We analyzed AKI in adult myeloablative CBT recipients who underwent transplantation from 2006 to 2017 for hematologic malignancies using cyclosporine A (CSA)/mycophenolate mofetil immunosuppression. Maximum grades of AKI were calculated using Kidney Disease: Improving Global Outcomes (grade 1, 1.5 to <2-fold; grade 2, 2 to <3-fold; or grade 3, ≥3-fold over baseline) definitions. In total, 153 patients (median 51 years [range, 23-65], 114/153 [75%] acute leukemia, 27/153 [18%] African, 88/153 [58%] cytomegalovirus seropositive, median age-adjusted hematopoietic cell comorbidity index 3 [range, 0-9], median pretransplant albumin 4.0 g/dL [range, 2.6-5.2]) underwent transplantation. The day 100 cumulative incidence of grade 1-3 AKI was 83% (95% confidence interval [CI], 77%-89%) (predominantly grade 2, median onset 40 days, range 0 to 96), and grade 2-3 AKI incidence was 54% (95% CI, 46%-62%) (median onset 43 days, range 0 to 96). Mean CSA level preceding AKI onset was high (360 ng/mL, target range 300-350). In multivariate analysis, African ancestry, addition of haploidentical CD34⁺ cells, low day -7 albumin, critical illness/intensive care admission, and nephrotoxic drug exposure (predominantly CSA and/or foscarnet) were associated with AKI. In a day 100 landmark analysis, 6% of patients with no prior AKI had chronic kidney disease (CKD) at 2 years versus 43% with prior grade 1 and 38% with prior grade 2-3 AKI (overall P= .02). Adult CBT recipients are at significant AKI risk, and AKI is associated with increased risk of CKD. Prevention strategies, early recognition, and prompt intervention are critical to mitigate kidney injury.

The association of the decline in glomerular filtration rate with aggressive endometrial cancers

PURPOSE

Most site-specific cancer incidence is increased with the decrease of glomerular filtration rate (GFR). We analyzed endometrial cancers depending on different type, staging, and histology grades. We hypothesized that patients with lower GFR levels have an increased risk for higher staging and histology grades of endometrial cancers.

METHODS

Patients were divided into two subgroups regarding GFR; the first group with GFR < 60 ml/min and the second group with GFR > 60 ml/min and regarding different histology grades and cancer stages. Cancers were also divided by stages (1-4). Patients were followed up during 1 year through regular controls in the outpatient clinic and during that time cancer recurrence was recorded.

RESULTS

GFR was the strongest predictor for higher cancer histology grade and higher cancer staging. Patients with reduced GFR had OR for higher histology grade and higher staging of 1.06 and 1.06. Traditional risk factors for endometrial cancer development were not associated with higher histology grade or higher cancer staging.

CONCLUSION

Higher staging and histology grades in patients with endometrial cancers are associated with reduced GFR. Patients with mild-to-moderate CKD had significantly higher number of cancers with higher histology grades and higher stages than patients with mild or normal GFR category. Decline in GFR was independently associated with more aggressive cancers without other well-known risk factors for endometrial cancer development like age, menopause, diabetes, and obesity.

The association of preoperative reduced glomerular filtration rate with higher staging and histology grades in patients with urinary tract cancers

PURPOSE

Studies have shown the increased incidence of urinary tract cancers which are associated with a decrease in glomerular filtration rate (GFR). We hypothesized that patients with GFR < 60 ml/min/1.73 m² have an increased risk for higher staging and histology grades of cancers and, therefore, the increased risk for cancer recurrence and cancer-related death.

METHODS

Retrospective clinical data and pathology reports were completed for 2116 patients. Patients were divided into two subgroups regarding GFR; the first group with GFR < 60 ml/min/1.73 m² and the second group with GFR > 60 ml/min/1.73 m² and regarding cancer recurrence. Cancers were also divided by stages (1-4) according to TNM classification. Patients were followed-up during 3 years.

RESULTS

We have found significantly higher number of cancers with higher histology grades and higher staging in group of patients with GFR < 60 ml/min/1.73 m² in all urinary tract localizations. GFR was the strongest predictor for higher cancer histology grade and only significant predictor for higher cancer staging. Patients with GFR < 60 ml/min/1.73 m² had OR for higher histology grade, higher staging, and cancer recurrence of 10.7, 5.3, and 11.3 compared to patients with GFR > 60 ml/min.

CONCLUSIONS

Higher staging and histology grades in patients with urinary tract cancers are associated with reduced GFR. Reduced GFR in these patients is a risk factor for cancer recurrence and cancer-related survival. Possible involvement of uremic toxins must be taken into account especially when cancers are predominantly located in estrogen sensitive organs. These patients should be intensively monitored and probably be more aggressively treated.

Biochemical evaluation of kidney disease

Different biochemical markers exist in both blood and urine for assessing renal function. Most of these biomarkers have advantages and limitations associated with their use, which is important to consider when ordering and utilising them in the clinical setting. The ideal marker should be able to detect acute kidney injury (AKI) at the onset and be used for the diagnosis and ongoing monitoring and management of kidney disease. The search for such a marker is ongoing, as all potential candidates thus far are associated with certain limitations. This article will attempt to compare and contrast established and emerging kidney disease markers.

Renal Dysfunction after Living-Donor Liver Transplantation: Experience with 500 Cases

Introduction. The possible risk factors for chronic kidney disease in transplant recipients have not been thoroughly investigated after living-donor liver transplantation. Material and Methods. A retrospective cohort study of consecutive adults who underwent living-donor liver transplantation between May 2004 and October 2016, in a single center, was conducted. Kidney function was investigated successively for all the patients throughout the study period, with 12 months being the shortest follow-up. Postoperative renal dysfunction was defined in accordance with the Chronic Kidney Disease Epidemiology Collaboration criteria. The patients' demographic data, preoperative and intraoperative parameters, and outcomes were recorded. A calcineurin inhibitor-based immunosuppressive regimen, either tacrolimus or cyclosporine, was used in all the patients. Results. Of the 413 patients included in the study, 33 (8%) who survived for ≥1 year experienced chronic kidney disease 1 year after living-donor liver transplantation. Twenty-seven variables were studied to compare between the patients with normal kidney functions and those who developed chronic kidney disease 1 year after living-donor liver transplantation. Univariate regression analysis for predicting the likelihood of chronic kidney disease at 1 year revealed that the following 4 variables were significant: operative time, P < 0.0005; intraoperative blood loss, P < 0.0005; preoperative renal impairment, P = 0.001; and graft-to-recipient weight ratio (as a negative predictor), P < 0.0005. In the multivariate regression analysis, only 2 variables remained as independent predictors of chronic kidney disease at 1 year, namely, operative time with a cutoff value of ≥714 minutes and graft-to-recipient weight ratio as a negative predictor with a cutoff value of <0.91. Conclusion. In this study, prolonged operative time and small graft-to-recipient weight ratio were independent predictors of chronic kidney disease at 1 year after living-donor liver transplantation.

Changes in Trace Elements During Early Stages of Chronic Kidney Disease in Type 2 Diabetic Patients

Trace elements can influence glucose metabolism and be related to oxidative stress in type 2 diabetes mellitus. Moreover, trace elements play important roles in the nephrotic complications of these patients. Nevertheless, few investigations have been made into the changes in the levels of trace elements in diabetic patients at various stages of chronic kidney disease (CKD). The aims of this present study were to determine the levels of some important trace elements in diabetic patients during the early stages of CKD and to identify the relationship between these elements and CKD progression in type 2 diabetic patients. One hundred and forty-eight type 2 diabetic patients with chronic kidney diseases were recruited into this study. The subjects were grouped into four stages (1, 2, 3a, 3b) of CKD, according to their urine protein levels and estimated glomerular filtration rates (eGFRs). The levels of serum zinc and iron exhibited a statistically significant decreasing trend (P trend = 0.032 and 0.047, respectively) from stage 1 to stage 3b after adjustment for age, gender, smoking, alcohol consumption, education, hypertension, and body mass index. The other tested elements, including copper, magnesium, selenium, chromium, and manganese, did not display any significant trends upon proceeding from stage 1 to stage 3b. Thus, serum zinc and iron appear to be useful markers when evaluating the early progression of CKD in type 2 diabetic patients.

The Divalent Elements Changes in Early Stages of Chronic Kidney Disease

As the glomerular filtration rate (GFR) decreases, it can cause imbalance in some divalent elements. These imbalances can cause increased oxidative stress in patients with renal impairment. The aim of present study was to investigate the changes of these divalent elements with CKD progression. One hundred and ninety-four patients with chronic kidney diseases (CKD) were divided into five stages, stage 1, 2, 3a, 3b, 4, and were recruited into this study. The divalent elements, calcium, magnesium, phosphorus, as well as iron, zinc, and copper were determined in clinical chemistry analyzer. Higher CKD stages were found to be associated with increased levels of phosphorus and copper; P_trend values were 0.002 and 0.004, respectively. Also, higher CKD stages were associated with decreased levels of zinc; P_trend value was 0.002, after adjustment for age, gender, smoke, education, diabetes, hypertension, and BMI. Decreased levels of zinc and elevated levels of phosphorus and copper might increase the oxidative stress and complications in CKD patients. Future randomized studies are needed to show whether adjusting dietary intake of phosphorus, copper, and zinc might affect the progression of CKD.

GFR estimation: from physiology to public health

Estimating glomerular filtration rate (GFR) is essential for clinical practice, research, and public health. Appropriate interpretation of estimated GFR (eGFR) requires understanding the principles of physiology, laboratory medicine, epidemiology, and biostatistics used in the development and validation of GFR estimating equations. Equations developed in diverse populations are less biased at higher GFRs than equations developed in chronic kidney disease (CKD) populations and are more appropriate for general use. Equations that include multiple endogenous filtration markers are more precise than equations including a single filtration marker. The CKD-EPI (CKD Epidemiology Collaboration) equations are the most accurate GFR estimating equations that have been evaluated in large diverse populations and are applicable for general clinical use. The 2009 CKD-EPI creatinine equation is more accurate in estimating GFR and prognosis than the 2006 MDRD (Modification of Diet in Renal Disease) Study equation and provides lower estimates of prevalence of decreased eGFR. It is useful as a "first test" for decreased eGFR and should replace the MDRD Study equation for routine reporting of serum creatinine-based eGFR by clinical laboratories. The 2012 CKD-EPI cystatin C equation is as accurate as the 2009 CKD-EPI creatinine equation in estimating GFR, does not require specification of race, and may be more accurate in patients with decreased muscle mass. The 2012 CKD-EPI creatinine-cystatin C equation is more accurate than the 2009 CKD-EPI creatinine and 2012 CKD-EPI cystatin C equations and is useful as a confirmatory test for decreased eGFR as determined by serum creatinine-based eGFR. Further improvement in GFR estimating equations will require development in more broadly representative populations, including diverse racial and ethnic groups, use of multiple filtration markers, and evaluation using statistical techniques to compare eGFR to "true GFR."

The prevalence of chronic kidney disease in the general population in Romania: a study on 60,000 persons

INTRODUCTION

Chronic kidney disease (CKD) is a major public health problem worldwide, due to its epidemic proportions and to its association with high cardiovascular risk. Therefore, screening for CKD is an increasingly important concept, aiming for early detection and prevention of progression and complications of this disease.

MATERIALS AND METHODS

We studied the prevalence of CKD in the adult population of Iaşi, the largest county in Romania, based on the results of a national general health screening program from 2007 to 2008. The patients were tested for CKD with serum creatinine and urinary dipstick. We used two different methods to estimate the glomerular filtration rate (eGFR): the simplified Modification of Diet in Renal Disease (MDRD) and the CKD Epidemiology Collaboration (CKD-EPI) equations. Based on the Kidney Disease Improving Global Outcomes (KDIGO) criteria, we defined CKD as the presence of either eGFR < 60 ml/min/1.73 m(2) and/or dipstick proteinuria. The classification of CKD by stage was also done according to the KDIGO criteria.

RESULTS

The study population included 60,969 people. The global prevalence of CKD was found to be 6.69% by the MDRD formula and 7.32% when using the CKD-EPI equation. The prevalence of CKD was much higher in women than in men: 9.09% versus 3.7%, by MDRD, and 9.32% versus 4.85%, by CKD-EPI. By age groups, the prevalence of CKD was 0.95% and 0.64% in persons aged 18-44 years old, 4.27% and 3.57% (45-64 years old), 13.36% and 15.34% (65-79 years old), and 23.59% and 34.56% (>80 years old), according to MDRD and CKD-EPI, respectively. By stages, the prevalence of CKD stage 3a (eGFR 59 to 45 ml/min/1.73 m(2)) was 5.72% by MDRD and 5.96% according to CKD-EPI, whereas the prevalence of stages 3b, 4, and 5 taken together (eGFR < 45 ml/min/1.73 m(2)) was 0.96% (MDRD) and 1.35% (CKD-EPI). Patients with CKD were significantly older (71.0 years versus 53.7 years) and had lower levels of serum Hb, total cholesterol, and glutamic pyruvic transaminase, and significantly higher serum creatinine and blood glucose, in comparison with the individuals without CKD. Impaired fasting glucose (106 mg/dl) was found in the CKD population, but not in non-CKD individuals.

CONCLUSIONS

Our study is one of the largest ever reported on the prevalence of CKD worldwide, the first one in Romania, and one of the very few of its kind in Europe (particularly in Eastern Europe). The study showed that the prevalence of CKD in our country is around 7%, which is lower than in other countries; however, this could be underestimated due to population selection bias. The prevalence is similar with the MDRD and the CKD-EPI equations; it increases with age and is much higher in women than in men. Impaired fasting glucose was detected in CKD patients, a finding that should probably raise the awareness of the high cardiovascular risk associated with CKD.

Chronic kidney disease staging in nursing home and community older adults: does the choice of cockcroft-gault, modification of diet in renal disease study, or the chronic kidney disease epidemiology collaboration initiative equations matter?

OBJECTIVE

To compare the chronic kidney disease (CKD) stages derived from GFR estimates using 3 different formulae in a sample of older adults from the community and long term care settings.

PARTICIPANTS

Data from 1535 older, hospitalized patients (2000-2008) were collected; individuals were hospitalized for acute illness unrelated to renal function.

MEASUREMENTS

Patient demographics, pertinent medical history, and routine laboratory test results were collected. Estimate of glomerular filtration rate and creatinine clearance values were determined by the Cockcroft-Gault, Modification of Diet in Renal Disease Study, and Chronic Kidney Disease Epidemiology Collaboration equations.

RESULTS

The Cockcroft-Gault equation generated significantly lower mean estimate of glomerular filtration rate values than either Modification of Diet in Renal Disease Study or Chronic Kidney Disease Epidemiology Collaboration equations in the total sample (P < .0005) and in a subset of patients diagnosed as renal insufficiency (P < .00005). Using the 3 formulae produced a significant disconnect in CKD staging resulting in the potential for different recommendations for monitoring and management across formulae (National Kidney Foundation Guidelines) (P < .0005). When stratified by age, the 3 equations produce nearly identical glomerular filtration rate estimates in patients younger than 70 years (P = .989) but significantly different glomerular filtration rate estimates in patients from 70 to 104 years (P < .0005).

CONCLUSIONS

The Cockcroft-Gault equation systematically provides lower (more severe) estimates of renal function than the Modification of Diet in Renal Disease Study and Chronic Kidney Disease Epidemiology Collaboration equation in patients older than 70 years. However, significant differences in CKD staging derived from estimate of glomerular filtration rate or creatinine clearance were not observed in adults from 59 to 69 years of age. These findings do not validate one formula over the others, but demonstrate that disparities exist; it may be prudent to use the same formula over time in a given patient to monitor changes in renal function.