24-hour Creatinine Clearance Research Articles

Concordancia en pacientes críticos entre las ecuaciones diseñadas para la estimación del filtrado glomerular y el aclaramiento de creatinina en orina de 24 h

Objective To study the behavior of the different equations used to estimate glomerular filtration rate (GFR) applied to critical care patients compared to the standard method: 24-hour creatinine clearance (24-CrCl). Design Retrospective analysis of data base from a previous observational prospective study. Setting Polyvalent ICU in a tertiary Hospital. Population All adult patients admitted to our Unit during the study who had a bladder catheter inserted. Anuric patients were excluded. Interventions We measured 24-CrCl and estimated GFR by MDRD, modified Jelliffe (JF), Mayo-Clinic (CM) and Cockroft-Gault (C-G) equations. Variables To evaluate degree of agreement, we grouped patients regarding 24-CrCl as normal (>70), moderate dysfunction (69–50) or severe renal dysfunction (< 50 mL/min/1.73 m 2). Results 307 patients, aged 54±18, 69.7% males. Measured 24-CrCl was 109.2±78.2 mL/min/1.73 m 2 and the estimate one 95.5±56.7 for JF, 87.4±53.4 for C-G, 86.9±55.9 for MDRD and 85.6±39.9 for CM. The difference was significant (p<0.001) for all estimates but lower for (13.7±53.2 mL/min/1.73 m 2) than C-G (21.9±58.3), CM (23.6±59.6) or MDRD (22.3±60.4). Correlation coefficient was 0.73 for JF, 0.67 C-G or CM and 0.64 for MDRD. The degree of agreement was only fair for all measures (Kappa 0.55 for JF or MDRD, 0.51 for C-G and 0.5 for CM). Conclusions Modified Jelliffe equation showed higher agreement with 24-CrCl than Cockroft-Gault, MDRD or Mayo-Clinic equations when used in critically ill patients. However, when exact measurement is needed, none of the equations can be considered adequate and in these cases, the CrCl should be calculated.

Performance of Simplified Modification of Diet in Renal Disease and Cockcroft-Gault Equations in Patients With Chronic Spinal Cord Injury and Chronic Kidney Disease

IntroductionThe purpose of the study was to compare the performance of the simplified Modification of Diet in Renal Disease (MDRD) and Cockcroft-Gault (CG) equations with 24-hour urinary creatinine clearance (Ccr) in patients with spinal cord injury (SCI) and chronic kidney disease. MethodsA retrospective diagnostic accuracy study of 116 patients with chronic SCI followed at the Memphis Veterans Affairs Medical Center Spinal Cord Injury Unit with measured Ccr (mCcr) <90mL/min/1.73m2. ResultsLinear regression analysis relating estimated glomerular filtration rate (eGFR) to mCcr showed a highly significant correlation between mCcr and eGFR (n=116; r=0.81, r2=0.65, P<0.0001); however, the relationship was more variable in the quadriplegic subjects (n=52; r=0.74, r2=0.54, P<0.0001) than in the paraplegic subjects (n=64; r=0.86, r2=0.73, P<0.0001). Both eGFR equations overestimated glomerular filtration rate (GFR) at all ranges of GFR in both subgroups of paraplegic subjects and quadriplegic subjects, with an MDRD fractional prediction error of 49% and 62%, respectively. Addition of a correction factor of 0.7 for MDRD and 0.8 for CG equations resulted in clinically acceptable fractional prediction error (below 20%) in both subgroups, especially in paraplegics with 3.9% and 3.6%, respectively. There was marked improvement in the performances of both eGFR equations, with better accuracy and precision after application of the correction factors. ConclusionsBoth MDRD and CG equations overestimate GFR in patients with chronic SCI at all stages of chronic kidney disease, particularly in quadriplegic subjects. An empirically derived correction factor markedly improved the performance and accuracy of both prediction equations.

Predictive Factors for Resolution of Congenital High Grade Vesicoureteral Reflux in Infants: Results of Univariate and Multivariate Analyses

We studied variables with impact on cessation of congenital high grade vesicoureteral reflux in univariate analyses and provide a multivariate model for prediction of reflux resolution. A total of 80 male and 35 female infants (median age 2.7 months) were included in this prospective observational study. Of the cases 71% were diagnosed after urinary tract infection and 26% after prenatal ultrasound. Reflux was bilateral in 70% of the patients and maximum grade was III in 16%, IV in 45% and V in 39%. The study protocol included repeat videocystometries, renal scintigrams, chromium edetic acid clearances and free voiding observations. Median followup was 36 months. Overall spontaneous reflux resolution, including cases downgraded to grade I to II, was 38%. Variables significantly negatively correlated to resolution were breakthrough febrile urinary tract infection, bladder dysfunction, higher grade of reflux at inclusion, renal abnormality, subnormal renal function, increased bladder capacity, residual urine and passive occurrence of reflux. Multivariate Cox proportional hazard model with stepwise selection identified 3 independent predictors--renal abnormality (hazard ratio 0.45, 95% CI 0.31-0.64, p <0.0001), bladder dysfunction (hazard ratio 0.43, 95% CI 0.29-0.64, p <0.0001) and breakthrough urinary tract infection (hazard ratio 0.38, 95% CI 0.18-0.78, p = 0.009). Performance of the model was evaluated by the receiver operating characteristic curve, with a calculated area under the curve of 83%. Overall resolution rate in congenital high grade vesicoureteral reflux is high during the first years of life. By multivariate analyses renal abnormality, bladder dysfunction and breakthrough febrile urinary tract infection were identified as strong independent negative predictive factors for reflux resolution.

Renoprotective Effects of Various Angiotensin II Receptor Blockers in Patients with Early-Stage Diabetic Nephropathy

Background: There is increasing evidence that inhibition of the renin-angiotensin system provides renoprotection independent of blood pressure lowering. The aim of the present study was to determine whether various angiotensin II receptor blockers (ARBs) affect urinary albumin excretion (UAE), urinary liver-type fatty acid-binding protein (L-FABP) and 8-hydroxy-2′-deoxyguanosine (8-OHdG) levels in early-stage diabetic nephropathy patients with microalbuminuria. Methods: Sixty-eight diabetic nephropathy patients with microalbuminuria were randomly allocated to 1 of 4 treatment groups: losartan 100 mg/day (group A), candesartan 12 mg/day (group B), olmesartan 40 mg/day (group C), or telmisartan 80 mg/day (group D). Treatment was continued for 12 months. UAE, L-FABP and 8-OHdG excretion, serum creatinine, and 24-hour creatinine clearance (Ccr) were measured. Results: The serum creatinine and 24-hour Ccr were not affected during the experimental period in any of the groups. Systolic and diastolic blood pressures, UAE, urinary L-FABP and 8-OHdG excretion were significantly reduced after 6 and 12 months compared with baseline in any of the groups. ΔL-FABP and Δ8-OHdG were significantly greater in group D than in the other 3 groups after 12 months. Conclusions: ARBs have renoprotection and this effect of telmisartan appears to be more potent than that of losartan, candesartan, or olmesartan in early-stage diabetic nephropathy patients.

Diagnostic value of cystatin C for predicting acute kidney injury in patients with liver cirrhosis

Background/AimsThe present study aimed to determine the role of cystatin C as a prognostic factor for acute kidney injury and survival in cirrhotic patients.MethodsThe study investigated 53 liver cirrhosis patients. The renal function was evaluated by serum creatinine, serum and urine cystatin C, and 24-hour creatinine clearance on admission. Acute kidney injury was defined as a serum creatinine level exceeding the normal range (>1.2 mg/dl) and an increase of at least 50% from the baseline value. Multivariate analysis, receiver operating characteristic curve, and survival analysis were used to investigate prognostic factors for acute kidney injury and survival.ResultsNine of the 53 cirrhotic patients (17.0%) developed acute kidney injury within 3 months. Both serum creatinine and cystatin C were predictive factors for acute kidney injury in univariate analysis, with a diagnostic accuracy of 0.735 (95% confidence interval (CI), 0.525-0.945; p=0.028) for serum cystatin C and 0.698 (95% CI, 0.495-0.901, p=0.063) for creatinine. In multivariate analysis, only serum cystatin C was an independent risk factor for acute kidney injury. The sensitivity and specificity of a serum cystatin C level of >1.23 mg/L to acute kidney injury were 66% and 86%, respectively. Serum cystatin C was positively correlated with the Model for End-Stage Liver Disease (MELD) and MELD-Na scores (r=0.346 and p=0.011, and r=0.427 and p=0.001, respectively). Comparison of the survival rates over the observation period revealed that a serum cystatin C level of >1.23 mg/L was a useful marker for short-term mortality (p<0.001).ConclusionsThe accuracy in predicting acute kidney injury and short-term mortality was higher for a serum cystatin C level of >1.23 mg/L than for the serum creatinine concentration in patients with cirrhosis.

Pharmacokinetics of Laropiprant and Glucuronide Metabolite in Patients with Severe Renal Insufficiency

Flushing symptoms limit the use of niacin as an effective treatment for dyslipidemia; laropiprant, a prostaglandin D2 receptor subtype 1 antagonist, reduces niacin-induced flushing and is being developed in combination with niacin. The aims of this study were to both determine the effect of renal insufficiency on plasma pharmacokinetics of laropiprant and to assess safety and tolerability in patients with severe renal insufficiency. This open-label study compared the pharmacokinetics of a single laropiprant 40-mg dose in 8 nondialyzed, severe renal insufficiency patients (RIs) with healthy matched subjects (HSs) (24-hour creatinine clearance <30 mL/min/1.73 m(2) and >80 mL/min/1.73 m(2) for RIs and HSs, respectively). In RIs, laropiprant was well tolerated and the area under the concentration time curve (AUC(0-infinity)) was modestly higher (ratio of geometric least-squares means [GMR] for RIs to HSs was 1.58; 90% confidence interval [CI], 1.06-2.35); neither the maximum laropiprant plasma concentration (C(max)) nor the time to C(max) (T(max)) was significantly affected. The apparent terminal half-life (t(1/2)) was 26.0 and 14.8 hours for RIs and HSs, respectively (P = 0.007). Similarly, for the inactive laropiprant glucuronide metabolite, the GMR for AUC(0-infinity) was 2.17 (90% CI, 1.44-3.27), and the apparent t(1/2) values were 25.3 to 14.5 hours (P = 0.037) in RIs and HSs, respectively. Renal insufficiency had no clinically significant effect on laropiprant pharmacokinetics. Because niacin and its metabolites are excreted through the kidneys, the combination of niacin with laropiprant should be used with caution in patients with renal impairment.

Effect of red wine on urinary protein, 8-hydroxydeoxyguanosine, and liver-type fatty acid–binding protein excretion in patients with diabetic nephropathy

The aim of the present study was to determine whether red or white wine affects urinary protein, 8-hydroxydeoxyguanosine (8-OHdG), and liver-type fatty acid–binding protein (L-FABP) excretion in type 2 diabetic nephropathy patients. Twenty-four type 2 diabetes mellitus patients with nephropathy were randomly allocated to drink a 118-mL (4-oz) glass of red wine (n = 12, group A) or white wine (n = 12, group B) daily for 6 months. Twelve type 2 diabetes mellitus patients with nephropathy who did not drink any wines served as control subjects (group C). Serum creatinine, 24-hour creatinine clearance, hemoglobin A 1c, urinary protein, urinary 8-OHdG, and urinary L-FABP were measured before and 3 and 6 months after the start of the study. In groups A, B, and C, serum creatinine, 24-hour creatinine clearance, and hemoglobin A 1c changed little during the experimental period. However, urinary protein, 8-OHdG, and L-FABP excretions were significantly decreased at 3 ( P < .05) and 6 months ( P < .01) compared with the baseline values in group A. In contrast, these markers changed little during the experimental period in groups B and C. Thus, these urinary markers were significantly lower in group A than in groups B and C at 3 and 6 months. These results suggest that red wine is renoprotective whereas white wine has no such effect in type 2 diabetes mellitus patients with nephropathy. The renoprotective effect of red wine may be due in part to its ability to reduce oxidative stress.

Independent determinants of soluble form of receptor for advanced glycation end products in elderly hypertensive patients

Advanced glycation end product receptor (RAGE) interaction plays an important role in atherosclerosis. Although exogenously administered soluble form of RAGE (sRAGE) has been shown to suppress the development and progression of atherosclerosis in animals, the kinetics and role of endogenous sRAGE in humans are not fully understood. In this study, to clarify whether endogenous sRAGE could capture and efficiently eliminate RAGE ligands such as circulating AGEs and high-mobility group box–1 (HMGB-1), we investigated the correlation between sRAGE and RAGE ligands and examined independent determinants of serum levels of sRAGE in hypertensive humans. Two-hundred seventy-one consecutive nondiabetic outpatients with essential hypertension (83 male and 188 female; mean age, 76.5 ± 9.2 yeas) underwent a complete history, physical examination, and determination of blood chemistries, including serum levels of sRAGE, AGEs, and HMGB-1. Univariate regression analysis showed that serum levels of sRAGE were associated with body mass index ( r = −0.313, P < .0001), waist ( r = −0.214, P < .0001), alanine aminotransferase ( r = −0.172, P = .005), γ-glutamyltranspeptidase ( r = −0.213, P < .0001), 24-hour creatinine clearance ( r = −0.348, P < .0001), B-type natriuretic peptide ( r = 0.138, P = .027), tumor necrosis factor– α ( r = 0.138, P = .002), and alcohol intake ( r = −0.155, P = .010). By the use of multiple stepwise regression analyses, 24-hour creatinine clearance ( P < .0001), γ-glutamyltranspeptidase ( P < .001), body mass index ( P = .007), and tumor necrosis factor– α ( P = .024) remained significant independently. The present study demonstrated for the first time that there was no significant correlation between serum levels of sRAGE and RAGE ligands such as circulating AGEs and HMGB-1 in hypertensive patients. Anthropometric and inflammatory variables and liver and renal function may be the determinants of endogenous sRAGE levels in nondiabetic hypertensive patients.

Dose Individualization Can Minimize Nephrotoxicity due to Carboplatin Therapy in Patients With Ovarian Cancer

Carboplatin (Carbo-Pt), an alkylating agent cleared from the plasma through glomerular filtration, is commonly used for the treatment of ovarian cancer. When administered at high dosage or to patients with reduced renal function, Carbo-Pt may be nephrotoxic. The dose of Carbo-Pt is calculated with Calvert formula, using the value of 24-hour creatinine clearance (24h Ccr) as an estimate of glomerular filtration rate (GFR). The aim of this study was to evaluate the possibility of individualizing the dose of Carbo-Pt using an alternative method to estimate GFR, based on body composition analysis, and then to assess the nephrotoxicity of Carbo-Pt therapy individualized with this new method. First, we evaluated the agreement between GFR (renal clearance of diethylene triamine pentaacetic acid (99mTc-DTPA)), 24h Ccr, and the new estimate of GFR (BCMGFR) calculated on the basis of individual values of body cell mass (BCM) and plasma creatinine. BCMGFR gave a better estimate of GFR than 24h Ccr. Then, we evaluated the nephrotoxicity of a combination chemotherapy based on Carbo-Pt (AUC(5-6)) in 23 patients affected by ovarian cancer. The dose of Carbo-Pt was adjusted to residual renal function of patients, evaluated as BCMGFR. No case of acute renal failure was observed with this treatment regimen. Urinary excretion of proteins (albumin, beta2-microglobulin, and retinol-binding protein) and tubular enzymes, measured as markers of tubular damage, increased significantly and transiently only in the first days after chemotherapy, whereas no evidence of chronic nephrotoxic effect was documented. Dose individualization, using the value of BCMGFR, may minimize nephrotoxicity due to Carbo-Pt therapy.

Over-increased creatinine renal clearance in septic patients and implications for vancomycin optimization

The hyperdynamic stage occurring in sepsis may be responsible for an increase in renal blood flow that may lead to increased elimination of some drugs, namely vancomycin. The aim of this study was to evaluate the effects of 24-hour creatinine clearance (CrCL) higher than 130 ml/min/1.73 m2on vancomycin serum levels, and to identify an accurate marker of this condition.

A Comparison of Prediction Equations for Estimating Glomerular Filtration Rate in Pregnancy

Objective: To compare existing glomerular filtration rate (GFR) prediction equations with the gold standard, inulin clearance, in pregnancy. Methods: Five equations were assessed for precision, bias, and accuracy in prediction of true GFR, measured by inulin clearance in 12 healthy, pregnant women during the second (T2) and third (T3) trimesters and in postpartum (PP). Results: Precision was greatest with 24-hour creatinine clearance estimation of GFR (R2 = 13% (T2), R2 = 26% (T3)). Other than 100/SCr, all equations underestimated true GFR. 30% accuracy was greatest in 100/SCr (83% (T2), 92% (T3)). Conclusions: Current GFR prediction formulae do not appear to be sufficient for estimating GFR in the gravid state.

A Comparison of the Predictive Performance of Different Methods of Kidney Function Estimation in a Well-Characterized HIV-Infected Population

Background: Glomerular filtration rate (GFR) estimation equations have never been validated in the HIV population. This pilot study aimed to compare all currently available methods of kidney function assessment with nuclear GFR in HIV-infected adults. Methods: Patients underwent GFR measurement with ^99mTc-diethylenetriaminepentaacetic acid (Tc-99m Pentetate), and measured values were compared with results of creatinine-based estimation equations [abbreviated 4-variable Modification of Diet in Renal Disease (MDRD) formula and Cockcroft-Gault (CG) formulae], 24-hour urine creatinine clearance and estimated cystatin C GFR. Results: Twenty-seven HIV-infected adults were studied. Most were male and Caucasian, with a mean age of 52 years. Median CD4 was 290 cells/mm³, 70% of patients had HIV RNA <50 copies/ml and all were receiving highly active antiretroviral therapy (median 5 drugs). Median Tc-99m Pentetate-GFR was 91 ml/min/1.73 m². Despite greater bias and similar accuracy, the MDRD formula was more precise than the CG formula, regardless of whether CG estimations were corrected for ideal body weight or body surface area. Relative accuracy within 30% of nuclear GFR was greater for the MDRD formula than for all other methods. The performance of 24-hour urine creatinine clearance was similar to that of the MDRD formula for patients with GFR <90 ml/min/1.73 m², although it performed less well at higher GFR. The performance of cystatin C GFR was inferior to that of all the creatinine-based methods. Conclusions: While no method of kidney function estimation performed highly, both 24-hour urine creatinine clearance and the MDRD formula performed with a level of precision and accuracy sufficient for clinical decision making. Our findings support the preferential use of the MDRD formula in the treated HIV population and suggest that there are no HIV-specific factors that limit equation applicability. Larger validation studies are needed to confirm our findings and allow generalization to the HIV population at large.

The Modification of Diet in Renal Disease (MDRD) and the Prediction of Kidney Outcomes After Lung Transplantation

Chronic kidney disease (CKD) is prevalent after lung transplantation. This study evaluated the ability of the 24-hour urine creatinine clearance (CrCl) and the Modification of Diet in Renal Disease (MDRD) equation at the time of listing to predict CKD after lung transplantation and to determine risk factors for CKD. This was a retrospective cohort study of 122 patients who underwent lung transplantation at Columbia Presbyterian Medical Center between May 2002 and August 2006. The primary end point was CKD Stage 3 or higher, defined as glomerular filtration rate (GFR) </= 59 ml/min/1.73 m(2) or renal replacement therapy, for at least 3 months. Patients were a mean age of 51 +/- 14 years, 55% women, and 83% non-Hispanic white. CKD developed in 62% by 1 year after lung transplantation. Older age, female gender, a diagnosis of sarcoidosis, and diabetes mellitus independently increased the risk of CKD (all p < 0.05). The MDRD equation was significantly better than CrCl at predicting CKD Stage 3 or higher at 1 year after transplantation, with an area under the receiver operating characteristic curve of 0.71 for MDRD (95% confidence interval [CI], 0.61-0.81) and 0.51 for CrCl (95% CI, 0.40-0.61) (P < 0.001). Older age, female gender, and diabetes mellitus increased the risk of developing CKD after lung transplant. The MDRD estimate of GFR at listing was a better predictor of CKD than CrCl. MDRD estimates should be used during lung transplant evaluation for risk stratification for CKD.

Retinol binding protein 4 concentrations are influenced by renal function in patients with type 2 diabetes mellitus

Retinol binding protein 4 (RBP-4), a newly discovered adipocytokine, has been involved in glucose and lipid metabolism. We assess the impacts of renal function on plasma RBP-4 levels in patients with type 2 diabetes mellitus with a wide range of nephropathy. Plasma RBP-4 levels were measured using the enzyme immunoassay method in 38 type 2 diabetes mellitus patients with nephropathy and were compared with those in 20 patients with normoalbuminuria. The levels of plasma RBP-4 were increased by 1.4- and 3.3-fold in patients with renal disease with macroalbuminuria ( P = .04) and end-stage renal disease (plasma creatinine level >2.0 mg/dL) ( P < .0001) compared with those in patients with normal renal function. In addition, RBP-4 levels were correlated with the creatinine level and 24-hour creatinine clearance (Ccr) on simple and multiple regression analyses in all patients. Furthermore, in patients having Ccr of more than 60 mL/min, RBP-4 levels were correlated with the homeostasis model assessment (HOMA)-r index and triglyceride (TGL) both on simple and multiple regression analyses. Interestingly, in patients having Ccr of less than 60 mL/min, RBP-4 levels were not correlated with the HOMA-r index and TGL on simple regression analysis. The RBP-4 concentrations are influenced by renal function in type 2 diabetes mellitus patients. In addition, RBP-4 levels were correlated with HOMA-r and TGL in diabetic subjects without end-stage renal disease.

A Study of the Predictive Method of 24-Hour Creatinine Clearance in Calculating the Appropriate Dosage of Carboplatin

The carboplatin (CBDCA) dosage is usually calculated using the formula of Calvert. Instead of the glomerular filtration rate (GFR), 24-h creatinine clearance (24 CLcr) is often used in this formula, which is calculated based on 24-h urine collection in clinical practice. We studied the adequacy of 24 CLcr in calculating the appropriate dosage of CBDCA using the formula of Calvert and compared CLcr and GFR using various substitutable predictive formulas (the formulae of Cockcroft and Gault, Yasuda, Orita, Jellife, Mawer, MDRD, and modified MDRD) when we were not able to use 24 CLcr. We retrospectively studied 193 patients who received CBDCA as chemotherapy during the period April 2004 through November 2006. We evaluated the adequacy of 24-h urine collection for measurement of creatinine production and excretion. We also evaluated the appropriate urine collection within a 15% range of the difference. The correlation between the appropriate 24 CLcr resulting in the urine collection and the CLcr or GFR was examined using past predictive formulae in the patients with appropriate urine collection. The accuracy of 24 CLcr was evaluated in 83 patients (43%). There was a significant correlation between CLcr or GFR using various predictive formulas and the appropriate 24 CLcr. There was an especially close and significant correlation with the formulae of Cockcroft and Gault and Yasuda (r>0.950, p<0.001). When using the Calvert formula, the accuracy of 24 CLcr should be evaluated. Patients evaluated as having inaccurate urinary collection should use the formulae of Cockcroft and Gault and Yasuda.

Predicting Glomerular Filtration Rate in Heart Transplant Recipients Using Serum Creatinine–based Equations With Cimetidine

In this study we evaluated the use of cimetidine on the performance of glomerular filtration rate (GFR) estimating equations and 24-hour creatinine clearance (24-hour CrCl) against radionuclide GFR in 43 heart transplant recipients with stable renal function. Pearson correlation coefficients for the 24-hour CrCl, Cockcroft-Gault, Nankivell and Modification of Diet in Renal Disease study (MDRD) equations without cimetidine were 0.76, 0.70, 0.81 and 0.76, and cimetidine-aided coefficients were 0.82, 0.80, 0.80 and 0.72, respectively. All the tested equations without cimetidine use predicted GFR with moderate accuracy in this population. The addition of cimetidine improved the predictive ability of the 24-hour CrCl and Cockcroft-Gault formulas, but not the Nankivell and MDRD GFR estimating equations, in heart transplant recipients.

Predictors of Faster Decline of Residual Renal Function in Taiwanese Peritoneal Dialysis Patients

Loss of residual renal function (RRF) in peritoneal dialysis (PD) patients is a powerful predictor of mortality. The present study was conducted to determine the predictors of faster decline of RRF in PD patients in Taiwan. The study enrolled 270 patients starting PD between January 1996 and December 2005 in a single hospital in Taiwan. We calculated RRF as the mean of the sum of 24-hour urea and creatinine clearance. The slope of the decline of residual glomerular filtration rate (GFR) was the main outcome measure. Data on demographic, clinical, laboratory, and treatment parameters; episodes of peritonitis; and hypotensive events were analyzed by Student t-test, Mann-Whitney U-test, and chi-square, as appropriate. All variables with statistical significance were included in a multivariate linear regression model to select the best predictors (p < 0.05) for faster decline of residual GFR. All patients commencing PD during the study period were followed for 39.4 +/- 24.0 months (median: 35.5 months). The average annual rate of decline of residual GFR was 1.377 +/- 1.47 mL/min/m(2). On multivariate analysis, presence of diabetes mellitus (p < 0.001), higher baseline residual GFR (p < 0.001), hypotensive events (p = 0.001), use of diuretics (p = 0.002), and episodes of peritonitis (p = 0.043) independently predicted faster decline of residual GFR. Male sex, old age, larger body mass index, and presence of coronary artery disease or congestive heart failure were also risk factors on univariate analysis. Our results suggested that diabetes mellitus, higher baseline residual GFR, hypotensive events, and use of diuretics are independently associated with faster decline of residual GFR in PD patients in Taiwan.

Assessment of Kidney Function in Lung Transplant Candidates

Glomerular filtration rate (GFR) is the best measure of kidney function; however, 24-hour creatinine clearance (CrCl) is the initial screening test used for lung transplant candidates at most centers. Although creatinine-based formulas that estimate GFR have been derived, none have been validated in patients with severe lung disease. We performed a retrospective cohort study of patients evaluated for lung transplantation at Columbia Presbyterian Medical Center and compared the GFR estimated from the Modification of Diet in Renal Disease (MDRD) and other formulas to the CrCl. We then validated these results in a cohort of patients evaluated at the Hospital of the University of Pennsylvania. There were strong and statistically significant direct correlations between estimated GFR and CrCl. An estimated GFR of <95 ml/min by the MDRD was very sensitive at detecting kidney dysfunction by CrCl in the derivation cohort. In the validation cohort, the negative predictive value of this cut-off was 97%. Established formulas for estimating GFR are highly discriminating for kidney dysfunction in patients being evaluated for lung transplantation and may actually have greater validity than CrCl in some instances.

Preservation of Renal Function Following Partial or Radical Nephrectomy Using 24-Hour Creatinine Clearance

ObjectiveTo compare the effect on renal function of partial and radical nephrectomy using creatinine clearance measurements from 24-hr urine collection. MethodsAll patients with a solid enhancing renal mass suspicious for renal cell carcinoma, a normal contralateral kidney, and not dialysis dependent were enrolled in this prospective cohort study. Patients were treated with partial or radical nephrectomy by one urologist. Creatinine clearance (CrCl) measurements were prospectively obtained by 24-hr urine collection preoperatively, and at 3, 6, and 12 mo postoperatively. Mean change in creatinine clearance from baseline was compared at 3, 6, and 12 mo. Serum creatinine and Cockcroft-Gault calculations were also performed for comparison.Mixed model analysis incorporating patient and tumor characteristics and the procedure type was performed in SAS Version 9.1. ResultsSixty-three consecutive patients were enrolled in this study. The partial nephrectomy (n=26) and radical nephrectomy (n=37) groups were similar with respect to age, sex, presence of hypertension, vascular disease, diabetes mellitus, and angiotensin converting enzyme inhibitor or receptor blocker use. The postoperative change in creatinine clearance was significantly less (p-value < 0.0001) in the partial nephrectomy group (−0.09mL/s, −6.1%) compared to the radical nephrectomy group (−0.56mL/s, −31.6%). Linear regression analysis showed intervention type (partial vs. radical nephrectomy) was the most significant predictor of change in creatinine clearance (p-value < 0.0001). ConclusionsThere is significantly less deterioration in the overall renal function of patients who are treated with partial nephrectomy compared to radical nephrectomy. This highlights the importance of performing nephron-sparing surgery on appropriate patients.

The Lipid lowering and Onset of Renal Disease (LORD) Trial: A randomized double blind placebo controlled trial assessing the effect of atorvastatin on the progression of kidney disease

BackgroundThere is evidence that dyslipidemia is associated with chronic kidney disease (CKD). Experimental studies have established that lipids are damaging to the kidney and animal intervention studies show statins attenuate this damage. Small clinical trials, meta-analyses, observational studies and post-hoc analyses of cardiovascular intervention studies all support the concept that statins can reduce kidney damage in humans. Based on this background, a double blind randomized placebo controlled trial was designed to assess the effectiveness of atorvastatin 10 mg on slowing the progression of kidney disease in a population of patients with CKD.Method/DesignThe Lipid lowering and Onset of Renal Disease (LORD) trial is a three-year, single center, multi-site, double blind, randomized, placebo controlled trial. The primary outcome measure is kidney function measured by eGFR calculated by both Modification of Diet in Renal Disease (MDRD) and Cockcroft and Gault equations. Secondary outcome measures include kidney function measured by 24-hour urine creatinine clearance and also 24-hour urinary protein excretion, markers of oxidative stress, inflammation and drug safety and tolerability.DiscussionThe results of this study will help determine the effectiveness and safety of atorvastatin and establish its effects on oxidative stress and inflammation in patients with CKD.Trial RegistrationANZCTRN012605000693628