Publications by authors named "Flavio Gaspari"

71 Publications

Glomerular resistances predict long-term GFR decline in type 2 diabetic patients without overt nephropathy: a longitudinal subgroup analysis of the DEMAND trial.

Acta Diabetol 2021 Oct 14. Epub 2021 Oct 14.

Department of Renal Medicine, Clinical Research Centre for Rare Diseases "Aldo e Cele Daccò": Istituto di Ricerche Farmacologiche Mario Negri IRCCS, Via GB Camozzi 3, 24020, Ranica, Bergamo, Italy.

Aims: Investigating whether and to what extent changes in glomerular hemodynamic parameters, beyond glomerular hyperfiltration, could predict glomerular filtration rate (GFR) decline in hypertensive, non-proteinuric type 2 diabetic patients.

Materials And Methods: We estimated baseline afferent (Ra) and efferent (Re) arteriolar resistances and glomerular hydrostatic pressure in 60 consecutive patients from DEMAND study, using the Gomez' equations. Baseline renal plasma flow was measured by para-aminohippurate plasma clearance, and GFR was measured by iohexol plasma clearance at baseline and every 6 months for a median of 4.0 years [IQR 3.5-4.0 years]. Patients with a GFR decline > or ≤ 3 mL/min/1.73 m/year were categorized as "Progressors" and "Non-progressors," respectively. Predictors of GFR decline were studied by univariable and multivariable logistic regression analysis.

Results: •The GFR declined by a median [IQR] of 4.06 [5.46-2.00] mL/min/1.73 m/year in the study group as a whole and by 5.35 [6.60-4.48] mL/min/1.73 m/year and 1.71 [2.14-1.33] mL/min/1.73 m/year in Progressors and Non-progressors, considered separately. Progressors had a higher baseline Ra (3487.3 ± 1349.3 dyne•sec•cm vs. 2877.0 ± 668.9 dyne•sec•cm, p < 0.05) and higher Ra/Re ratio (1.4 ± 0.5 vs. 1.1 ± 0.3, p < 0.01) than Non-progressors. At multivariable logistic regression analysis, Ra/Re ratio and arterial hypertension duration were independently associated with GFR decline (odds ratio [95% CI] 8.50 [1.56-46.28] and 1.14 [1.01-1.28]), respectively.

Conclusions: Increased Ra/Re ratio and arterial hypertension duration predict early GFR decline in hypertensive non-proteinuric type 2 diabetic patients. These findings could be explained by glomerular hypoperfusion and chronic ischemic injury related to pre-glomerular arteriolar narrowing.

Clinical Trial Registration: DEMAND, NCT00157586, September 12, 2005.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s00592-021-01804-9DOI Listing
October 2021

Preventing microalbuminuria with benazepril, valsartan, and benazepril-valsartan combination therapy in diabetic patients with high-normal albuminuria: A prospective, randomized, open-label, blinded endpoint (PROBE) study.

PLoS Med 2021 07 14;18(7):e1003691. Epub 2021 Jul 14.

Department of Renal Medicine, Clinical Research Center for Rare Diseases, "Aldo e Cele Daccò": Istituto di Ricerche Farmacologiche Mario Negri IRCCS, Ranica, Bergamo, Italy.

Background: Angiotensin converting enzyme (ACE) inhibitors and angiotensin receptor blockers (ARBs) prevent microalbuminuria in normoalbuminuric type 2 diabetic patients. We assessed whether combined therapy with the 2 medications may prevent microalbuminuria better than ACE inhibitor or ARB monotherapy.

Methods And Findings: VARIETY was a prospective, randomized, open-label, blinded endpoint (PROBE) trial evaluating whether, at similar blood pressure (BP) control, combined therapy with benazepril (10 mg/day) and valsartan (160 mg/day) would prevent microalbuminuria more effectively than benazepril (20 mg/day) or valsartan (320 mg/day) monotherapy in 612 type 2 diabetic patients with high-normal albuminuria included between July 2007 and April 2013 by the Istituto di Ricerche Farmacologiche Mario Negri IRCCS and 8 diabetology or nephrology units in Italy. Time to progression to microalbuminuria was the primary outcome. Analyses were intention to treat. Baseline characteristics were similar among groups. During a median [interquartile range, IQR] follow-up of 66 [42 to 83] months, 53 patients (27.0%) on combination therapy, 57 (28.1%) on benazepril, and 64 (31.8%) on valsartan reached microalbuminuria. Using an accelerated failure time model, the estimated acceleration factors were 1.410 (95% CI: 0.806 to 2.467, P = 0.229) for benazepril compared to combination therapy, 0.799 (95% CI: 0.422 to 1.514, P = 0.492) for benazepril compared to valsartan, and 1.665 (95% CI: 1.007 to 2.746, P = 0.047) for valsartan compared to combination therapy. Between-group differences in estimated acceleration factors were nonsignificant after adjustment for predefined confounders. BP control was similar across groups. All treatments were safe and tolerated well, with a slight excess of hyperkalemia and hypotension in the combination therapy group. The main study limitation was the lower than expected albuminuria at inclusion.

Conclusions: Risk/benefit profile of study treatments was similar. Dual renin-angiotensin system (RAS) blockade is not recommended as compared to benazepril or valsartan monotherapy for prevention of microalbuminuria in normoalbuminuric type 2 diabetic patients.

Trial Registration: EudraCT 2006-005954-62; ClinicalTrials.gov NCT00503152.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1371/journal.pmed.1003691DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8279302PMC
July 2021

Mycophenolate mofetil versus azathioprine in kidney transplant recipients on steroid-free, low-dose cyclosporine immunosuppression (ATHENA): A pragmatic randomized trial.

PLoS Med 2021 06 24;18(6):e1003668. Epub 2021 Jun 24.

Istituto di Ricerche Farmacologiche Mario Negri IRCCS, Bergamo, Italy.

Background: We compared protection of mycophenolate mofetil (MMF) and azathioprine (AZA) against acute cellular rejection (ACR) and chronic allograft nephropathy (CAN) in kidney transplant recipients on steroid-free, low-dose cyclosporine (CsA) microemulsion maintenance immunosuppression.

Methods And Findings: ATHENA, a pragmatic, prospective, multicenter trial conducted by 6 Italian transplant centers, compared the outcomes of 233 consenting recipients of a first deceased donor kidney transplant induced with low-dose thymoglobulin and basiliximab and randomized to MMF (750 mg twice/day, n = 119) or AZA (75 to 125 mg/day, n = 114) added-on maintenance low-dose CsA microemulsion and 1-week steroid. In patients without acute clinical or subclinical rejections, CsA dose was progressively halved. Primary endpoint was biopsy-proven CAN. Analysis was by intention to treat. Participants were included between June 2007 and July 2012 and followed up to August 2016. Between-group donor and recipient characteristics, donor/recipient mismatches, and follow-up CsA blood levels were similar. During a median (interquartile range (IQR)) follow-up of 47.7 (44.2 to 48.9) months, 29 of 87 biopsied patients on MMF (33.3%) versus 31 of 88 on AZA (35.2%) developed CAN (hazard ratio (HR) [95% confidence interval (CI)]: 1.147 (0.691 to 1.904, p = 0.595). Twenty and 21 patients on MMF versus 34 and 14 on AZA had clinical [HR (95% CI): 0.58 (0.34 to 1.02); p = 0.057) or biopsy-proven subclinical [HR (95% CI): 1.49 (0.76 to 2.92); p = 0.249] ACR, respectively. Combined events [HR (95% CI): 0.85 (0.56 to 1.29); p = 0.438], patient and graft survival, delayed graft function (DGF), 3-year glomerular filtration rate (GFR) [53.8 (40.6;65.7) versus 49.8 (36.8;62.5) mL/min/1.73 m2, p = 0.50], and adverse events (AEs) were not significantly different between groups. Chronicity scores other than CAN predict long-term graft outcome. Study limitations include small sample size and unblinded design.

Conclusions: In this study, we found that in deceased donor kidney transplant recipients on low-dose CsA and no steroids, MMF had no significant benefits over AZA. This finding suggests that AZA, due to its lower costs, could safely replace MMF in combination with minimized immunosuppression.

Trial Registration: ClinicalTrials.gov NCT00494741; EUDRACT 2006-005604-14.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1371/journal.pmed.1003668DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8224852PMC
June 2021

Long-Term Outcomes of Kidney Transplants from Older/Marginal Donors: A Cohort Study.

Nephron 2021 Jun 15:1-11. Epub 2021 Jun 15.

Istituto di Ricerche Farmacologiche Mario Negri IRCCS, Bergamo, Italy.

Introduction: To safely expand the donor pool, we introduced a strategy of biopsy-guided selection and allocation to single or dual transplantation of kidneys from donors >60 years old or with hypertension, diabetes, and/or proteinuria (older/marginal donors). Here, we evaluated the long-term performance of this approach in everyday clinical practice.

Methods: In this single-center cohort study, we compared outcomes of 98 patients who received one or two biopsy-evaluated grafts from older/marginal donors ("recipients") and 198 patients who received nonhistologically assessed single graft from ideal donors ("reference-recipients") from October 2004 to December 2015 at the Bergamo Transplant Center (Italy).

Results: Older/marginal donors and their recipients were 27.9 and 19.3 years older than ideal donors and their reference-recipients, respectively. KDPI/KDRI and donor serum creatinine were higher and cold ischemia time longer in the recipient group. During a median follow-up of 51.9 (interquartile range 23.1-88.6) months, 11.2% of recipients died, 7.1% lost their graft, and 16.3% had biopsy-proven acute rejection (BPAR) versus 3.5, 7.6, and 17.7%, respectively, of reference-recipients. Overall death-censored graft failure (rate ratio 0.78 [95% CI 0.33-2.08]), 5-year death-censored graft survival (94.3% [87.8-100.0] vs. 94.2% [90.5-98.0]), BPAR incidence (rate ratio 0.87 [0.49-1.62]), and yearly measured glomerular filtration rate decline (1.18 ± 3.27 vs. 0.68 ± 2.42 mL/min/1.73 m2, p = 0.37) were similar between recipients and reference-recipients, respectively.

Conclusions: Biopsy-guided selection and allocation of kidneys from older/marginal donors can safely increase transplant activity in clinical practice without affecting long-term outcomes. This may help manage the growing gap between organ demand and supply without affecting long-term recipient and graft outcomes.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1159/000516534DOI Listing
June 2021

Estimated GFR Slope in Kidney Transplant Patients: When the Error Is Random.

Transplantation 2021 Feb 23. Epub 2021 Feb 23.

IIS-Fundación Jiménez Diaz, Department of Medicine, School of Medicine, Universidad Autónoma de Madrid, 28029 Madrid, Spain Department of Nephrology, University Hospital of the Canary Islands, Tenerife, Spain Renal Function Laboratory, Universidad de La Laguna, Tenerife, Spain Central Laboratory, Hospital Universitario de Canarias, Tenerife, Spain Faculty of Medicine, Universidad de La Laguna, Tenerife, Spain Research Unit Department, Hospital Universitario de Canarias, Tenerife, Spain Red de Investigación Renal (REDINREN), Instituto Carlos III-FEDER, 28040 Madrid, Spain Internal Medicine Department, Universidad de La Laguna, Instituto de Tecnologías Biomédicas, Tenerife, Spain.

Background: The evaluation of renal function changes over time is crucial in day-to-day renal transplant care and a major outcome in clinical trials. Little is known about the reliability of estimated glomerular filtration rate (eGFR) in reflecting real GFR changes.

Methods: We analyzed the variability of eGFR slope by 63 equations in estimating measured GFR (mGFR) changes in 110 renal transplant patients. The agreement between eGFR and mGFR slopes was evaluated by the concordance correlation coefficient (CCC) and the limits of agreement (LA). Patients were grouped based on mGFR slope in rapid GFR loss: faster than -3 ml/min/year; stable renal function: -3 to +3 ml/min/year; and improvement in GFR: higher than +3 ml/min/year.

Results: CCC averaged 0.36 and LA ±10 ml/min/year, indicating very poor agreement between eGFR and mGFR slopes. eGFR slope classified patients into the same group of mGFR slope only in 25% of the cases. In about two thirds of patients, eGFR slope was either markedly faster or slower than mGFR slope. In half of these cases the discrepancy between mGFR and eGFR slopes was ≥50%.

Conclusions: Formulas are neither accurate nor precise in reflecting real GFR decline in renal transplant patients, making them unreliable for clinical practice and trials.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1097/TP.0000000000003719DOI Listing
February 2021

Iohexol plasma clearance simplified by Dried Blood Spot (DBS) sampling to measure renal function in conscious mice.

Sci Rep 2021 Feb 25;11(1):4591. Epub 2021 Feb 25.

Nephrology Department, Unidad de Ensayos Clinicos-UCICEC. Hospital Universitario de Canarias, Ofra s/n La Cuesta, 38320, La Laguna, S/C Tenerife, Spain.

There is no simple method to measure glomerular filtration rate (GFR) in mice, which limits the use of mice in models of renal diseases. We aimed at simplifying the plasma clearance of iohexol in mice, using dried blood spot (DBS) sampling in order to reduce the amount of blood taken for analysis. GFR was measured simultaneously by a reference method in total blood-as described before-and tested method using DBS in fifteen male and six female C57BL/6J mice. Total blood extraction was 50 μL for the reference methods and 25μL for the tested methods, distributed in 5 samples. The agreement of GFR values between both methods was analyzed with the concordance correlation coefficient (CCC), total deviation index (TDI) and coverage probability (CP). The agreement between both methods was excellent, showing a TDI = 8.1%, which indicates that 90% of the GFR values obtained with DBS showed an error ranging from - 8 to + 8% of the reference method; a CCC of 0.996 (CI: 0.992), reflecting high precision and accuracy and a CP of 94 (CI: 83), indicating that 6% of the GFR values obtained with DBS had an error greater than 10% of the method in blood. So, both methods are interchangeable. DBS represent a major simplification of GFR measurement in mice. Also, DBS improves animal welfare by reducing the total blood required and refining the procedure.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/s41598-021-83934-2DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7907335PMC
February 2021

A Simplified Iohexol-Based Method to Measure Renal Function in Sheep Models of Renal Disease.

Biology (Basel) 2020 Aug 31;9(9). Epub 2020 Aug 31.

Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA), Avda Pta. de Hierro s/n, 28040 Madrid, Spain.

Sheep are highly adequate models for human renal diseases because of their many similarities in the histology and physiology of kidney and pathogenesis of kidney diseases. However, the lack of a simple method to measure glomerular filtration rate (GFR) limits its use as a model of renal diseases. Hence, we aimed to develop a simple method to measure GFR based on the plasma clearance of iohexol by assessing different pharmacokinetic models: (a) CL2: two-compartment (samples from 15 to 420 min; reference method); (b) CL1: one-compartment (samples from 60 to 420 min); (c) CLl: CL1 adjusted by a correction formula and (d) SM: simplified CL2 (15 to 300 min). Specific statistics of agreement were used to test the models against CL2. The agreement between CL1 and CL2 was low, but both CL1 and SM showed excellent agreement with CL2, as indicated by a total deviation index of ~5-6%, a concordance correlation of 0.98-0.99% and a coverage probability of 99-100%, respectively. Hence, the SM approach is preferable due to a reduced number of samples and shorter duration of the procedure; two points that improve animal management and welfare.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/biology9090259DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7564881PMC
August 2020

Kidney transplant tolerance associated with remote autologous mesenchymal stromal cell administration.

Stem Cells Transl Med 2020 04 24;9(4):427-432. Epub 2019 Dec 24.

Istituto di Ricerche Farmacologiche Mario Negri IRCCS, Bergamo, Italy.

Here we report the case of successful immune tolerance induction in a living-donor kidney transplant recipient remotely treated with autologous bone marrow-derived mesenchymal stromal cells (MSC). This case report, which to the best of our knowledge is the first in the world in this setting, provides evidence that the modulation of the host immune system with MSC can enable the safe withdrawal of maintenance immunosuppressive drugs while preserving optimal long-term kidney allograft function.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/sctm.19-0185DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7103624PMC
April 2020

Reply to 'Strengths and limitations of estimated and measured GFR'.

Nat Rev Nephrol 2019 12;15(12):785-786

Istituto di Ricerche Farmacologiche Mario Negri IRCCS, Centro di Ricerche Cliniche per le Malattie Rare "Aldo e Cele Daccò", Ranica, Bergamo, Italy.

View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/s41581-019-0214-8DOI Listing
December 2019

Response to "Iohexol-measured glomerular filtration rate in children and adolescents with chronic kidney disease: a pilot study comparing venous and finger stick methods".

Pediatr Nephrol 2019 09 16;34(9):1629-1630. Epub 2019 Jun 16.

Instituto de Tecnologías Biomédicas, Universidad de La Laguna, Tenerife, Spain.

View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s00467-019-04285-9DOI Listing
September 2019

Octreotide-LAR in later-stage autosomal dominant polycystic kidney disease (ALADIN 2): A randomized, double-blind, placebo-controlled, multicenter trial.

PLoS Med 2019 04 5;16(4):e1002777. Epub 2019 Apr 5.

Istituto di Ricerche Farmacologiche Mario Negri IRCCS, Bergamo, Italy.

Background: Autosomal dominant polycystic kidney disease (ADPKD) is the most frequent genetically determined renal disease. In affected patients, renal function may progressively decline up to end-stage renal disease (ESRD), and approximately 10% of those with ESRD are affected by ADPKD. The somatostatin analog octreotide long-acting release (octreotide-LAR) slows renal function deterioration in patients in early stages of the disease. We evaluated the renoprotective effect of octreotide-LAR in ADPKD patients at high risk of ESRD because of later-stage ADPKD.

Methods And Findings: We did an internally funded, parallel-group, double-blind, placebo-controlled phase III trial to assess octreotide-LAR in adults with ADPKD with glomerular filtration rate (GFR) 15-40 ml/min/1.73 m2. Participants were randomized to receive 2 intramuscular injections of 20 mg octreotide-LAR (n = 51) or 0.9% sodium chloride solution (placebo; n = 49) every 28 days for 3 years. Central randomization was 1:1 using a computerized list stratified by center and presence or absence of diabetes or proteinuria. Co-primary short- and long-term outcomes were 1-year total kidney volume (TKV) (computed tomography scan) growth and 3-year GFR (iohexol plasma clearance) decline. Analyses were by modified intention-to-treat. Patients were recruited from 4 Italian nephrology units between October 11, 2011, and March 20, 2014, and followed up to April 14, 2017. Baseline characteristics were similar between groups. Compared to placebo, octreotide-LAR reduced median (95% CI) TKV growth from baseline by 96.8 (10.8 to 182.7) ml at 1 year (p = 0.027) and 422.6 (150.3 to 695.0) ml at 3 years (p = 0.002). Reduction in the median (95% CI) rate of GFR decline (0.56 [-0.63 to 1.75] ml/min/1.73 m2 per year) was not significant (p = 0.295). TKV analyses were adjusted for age, sex, and baseline TKV. Over a median (IQR) 36 (24 to 37) months of follow-up, 9 patients on octreotide-LAR and 21 patients on placebo progressed to a doubling of serum creatinine or ESRD (composite endpoint) (hazard ratio [HR] [95% CI] adjusted for age, sex, baseline serum creatinine, and baseline TKV: 0.307 [0.127 to 0.742], p = 0.009). One composite endpoint was prevented for every 4 treated patients. Among 63 patients with chronic kidney disease (CKD) stage 4, 3 on octreotide-LAR and 8 on placebo progressed to ESRD (adjusted HR [95% CI]: 0.121 [0.017 to 0.866], p = 0.036). Three patients on placebo had a serious renal cyst rupture/infection and 1 patient had a serious urinary tract infection/obstruction, versus 1 patient on octreotide-LAR with a serious renal cyst infection. The main study limitation was the small sample size.

Conclusions: In this study we observed that in later-stage ADPKD, octreotide-LAR slowed kidney growth and delayed progression to ESRD, in particular in CKD stage 4.

Trial Registration: ClinicalTrials.gov NCT01377246; EudraCT: 2011-000138-12.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1371/journal.pmed.1002777DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6450618PMC
April 2019

C5 Convertase Blockade in Membranoproliferative Glomerulonephritis: A Single-Arm Clinical Trial.

Am J Kidney Dis 2019 08 28;74(2):224-238. Epub 2019 Mar 28.

Istituto di Ricerche Farmacologiche Mario Negri IRCCS, Bergamo, Italy; L. Sacco Department of Biomedical and Clinical Sciences, University of Milan, Milan, Italy. Electronic address:

Rationale & Objective: Primary membranoproliferative glomerulonephritis (MPGN) is a rare glomerulopathy characterized by complement dysregulation. MPGN progresses rapidly to kidney failure when it is associated with nephrotic syndrome. We assessed the effects of C5 convertase blockade in patients with MPGN and terminal complement activation.

Study Design: Prospective off-on-off-on open-label clinical trial.

Setting & Participants: Consenting patients with immune complex-mediated MPGN (n=6) or C3 glomerulonephritis (n=4) with sC5b-9 (serum complement membrane attack complex) plasma levels>1,000ng/mL and 24-hour proteinuria with protein excretion>3.5g identified from the Italian Registry of MPGN and followed up at the Istituto di Ricerche Farmacologiche Mario Negri IRCCS (Bergamo, Italy) between March 4, 2014, and January 7, 2015.

Intervention: Anti-C5 monoclonal antibody eculizumab administered during 2 sequential 48-week treatment periods separated by one 12-week washout period.

Outcomes: Primary outcome was change in 24-hour proteinuria (median of 3 consecutive measurements) at 24 and 48 weeks.

Results: Median proteinuria decreased from protein excretion of 6.03 (interquartile range [IQR], 4.8-12.4) g/d at baseline to 3.74 (IQR, 3.2-4.4) g/d at 24 weeks (P=0.01) and to 5.06 (IQR, 3.1-5.8) g/d (P=0.006) at 48 weeks of treatment, recovered toward baseline during the washout period, and did not significantly decrease thereafter. Hypoalbuminemia, dyslipidemia, and glomerular sieving function improved during the first treatment period. 3 patients achieved partial remission of nephrotic syndrome and all had undetectable C3 nephritic factors before treatment. Mean measured glomerular filtration rate was 69.7±35.2 versus 87.4±55.1 and 75.8±42.7 versus 76.6±44.1mL/min/1.73m at the start versus the end of the first and second treatment periods, respectively, among all 10 study participants. Unlike C3, sC5b-9 plasma levels normalized during both treatment periods and recovered toward baseline during the washout in all patients.

Limitations: Single-arm design, small sample size.

Conclusions: Eculizumab blunted terminal complement activation in all patients with immune complex-mediated MPGN or C3 glomerulonephritis and nephrotic syndrome, but persistently reduced proteinuria in just a subgroup.

Trial Registration: Registered in the EU Clinical Trials Register with study no. 2013-003826-10.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1053/j.ajkd.2018.12.046DOI Listing
August 2019

Effects of valsartan, benazepril and their combination in overt nephropathy of type 2 diabetes: A prospective, randomized, controlled trial.

Diabetes Obes Metab 2019 05 22;21(5):1177-1190. Epub 2019 Feb 22.

Department of Renal Medicine, Clinical Research Centre for Rare Diseases "Aldo e Cele Daccò": Istituto di Ricerche Farmacologiche Mario Negri IRCCS, Ranica (Bergamo), Italy.

Aims: To evaluate whether angiotensin-converting enzyme (ACE) inhibitor and angiotensin II receptor blocker (ARB) combination therapy is more nephroprotective than ACE inhibitor or ARB monotherapy in people with type 2 diabetes and overt nephropathy.

Materials And Methods: In this prospective, randomized, open, blind-endpoint phase III trial sponsored by the Italian Drug Agency, 103 consenting patients with type 2 diabetes, aged >40 years, with serum creatinine levels 159 to 309 μmol/L, spot morning urinary albumin-creatinine ratio > 1000 mg/g (or > 500 mg/g in those on ACE inhibitor or ARB therapy at inclusion) were stratified by centre and randomized to 4.5-year treatment with valsartan 320 mg/d (n = 36), benazepril 20 mg/d (n = 34) or halved doses of both medications (n = 33). The primary endpoint was end-stage renal disease (ESRD). Modified intention-to-treat analyses were performed.

Results: Recruitment took place between June 2007 and February 2013 at 10 centres in Italy and one in Slovenia. A total of 77 participants completed the study and 26 were prematurely withdrawn. During a median (interquartile range) of 41 (18-54) months, 12 participants on benazepril (35.3%) and nine on combination therapy (27.3%) progressed to ESRD, versus five on valsartan (13.9%). Differences between benazepril (hazard ratio [HR] 3.59, 95% confidence interval [CI] 1.25-10.30; P = 0.018) or combination therapy (HR 3.28, 95% CI 1.07-10.0; P = 0.038) and valsartan were significant, even after adjustment for age, gender and baseline serum creatinine, systolic blood pressure and 24-hour proteinuria (HR 5.16, 95% CI 1.50-17.75, P = 0.009 and HR 4.75, 95% CI 1.01-22.39, P = 0.049, respectively). Adverse events were distributed similarly among the groups.

Conclusions: In people with type 2 diabetes with nephropathy, valsartan (320 mg/d) safely postponed ESRD more effectively than benazepril (20 mg/d) or than halved doses of both medications.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1111/dom.13639DOI Listing
May 2019

Author Correction: Estimated GFR: time for a critical appraisal.

Nat Rev Nephrol 2019 Feb;15(2):121

Nephrology and Dialysis Unit, Azienda Socio Sanitaria Territoriale Papa Giovanni XXIII, Bergamo, Italy.

In the version of this article originally published online, the middle initials of Aiko P. J. de Vries, an author on the manuscript, were omitted. The omission has been corrected in the PDF and HTML versions of the article.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/s41581-018-0105-4DOI Listing
February 2019

Estimated GFR: time for a critical appraisal.

Nat Rev Nephrol 2019 03;15(3):177-190

Nephrology and Dialysis Unit, Azienda Socio Sanitaria Territoriale Papa Giovanni XXIII, Bergamo, Italy.

Since 1957, over 70 equations based on creatinine and/or cystatin C levels have been developed to estimate glomerular filtration rate (GFR). However, whether these equations accurately reflect renal function is debated. In this Perspectives article, we discuss >70 studies that compared estimated GFR (eGFR) with measured GFR (mGFR), involving ~40,000 renal transplant recipients and patients with chronic kidney disease (CKD), type 2 diabetes mellitus or polycystic kidney disease. Their results show that eGFR often differed from mGFR by ±30% or more, that eGFR values incorrectly staged CKD in 30-60% of patients, and that eGFR and mGFR gave different rates of GFR decline. Errors were unpredictable, and comparable for equations based on creatinine and/or cystatin C. We argue, therefore, that the persistence of these errors (despite intensive research) suggests that the problem lies with using creatinine and/or cystatin C as markers of renal function, rather than with the mathematical methods used for GFR estimation.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/s41581-018-0080-9DOI Listing
March 2019

Long-Term Clinical and Immunological Profile of Kidney Transplant Patients Given Mesenchymal Stromal Cell Immunotherapy.

Front Immunol 2018 14;9:1359. Epub 2018 Jun 14.

IRCCS - Istituto di Ricerche Farmacologiche Mario Negri, Bergamo, Italy.

We report here the long-term clinical and immunological results of four living-donor kidney transplant patients given autologous bone marrow-derived mesenchymal stromal cells (MSCs) as part of a phase 1 study focused on the safety and feasibility of this cell therapy. According to study protocols implemented over time, based on initial early safety findings, the patients were given MSC at day 7 posttransplant ( = 2) or at day -1 pretransplant ( = 2) and received induction therapy with basiliximab and low-dose rabbit anti-thymocyte globulin (RATG) or RATG alone, and were maintained on low-dose ciclosporin (CsA)/mycophenolate mofetil (MMF). All MSC-treated patients had stable graft function during the 5- to 7-year follow-up, without increased susceptibility to infections or neoplasm. In three MSC recipients, but not historical control patients, circulating memory CD8 T cell percentages remained lower than basal, coupled with persistent reduction of donor-specific cytotoxicity. Two patients showed a long-lasting increase in the regulatory T cell/memory CD8 T cell ratio, paralleled by high circulating levels of naïve and transitional B cells. In one of these two patients, CsA was successfully discontinued, and currently the low-dose MMF monotherapy is on the tapering phase. The study shows that MSC therapy is safe in the long term and could promote a pro-tolerogenic environment in selected patients. Extensive immunomonitoring of MSC-treated kidney transplant recipients could help selection of patients for safe withdrawal of maintenance immunosuppressive drugs (NCT00752479 and NCT02012153).
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3389/fimmu.2018.01359DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6014158PMC
June 2018

Safety of Iohexol Administration to Measure Glomerular Filtration Rate in Different Patient Populations: A 25-Year Experience.

Nephron 2018 17;140(1):1-8. Epub 2018 May 17.

IRCCS-Istituto di Ricerche Farmacologiche Mario Negri, Bergamo, Italy.

Background/aim: In clinical research setting, accurate and precise measurement of glomerular filtration rate (GFR) is essential to overcome the limitations of GFR estimation with equations, which are often unreliable. In recent decades, a method for measuring GFR by plasma clearance of iohexol, a non-ionic radiocontrast agent, was developed. To evaluate the safety of the procedure, we aimed to review all immediate adverse reactions that could be related to iohexol administration in our group's 25 years worth of experience.

Methods: We retrospectively reviewed all GFR investigations in 2,891 patients, between 1992 and 2016, as part of 37 clinical trials coordinated by our group. Subjects with disparate renal diseases, kidney transplant recipients, and living donors - all with different renal function categories - were included in the surveyed clinical trials.

Results: During 15,147 GFR measurements, only one treatment-related event of moderate intensity was identified. Flushing, urticaria, and itching were observed in a diabetic patient a few minutes after iohexol administration during the first GFR measurement. The event recovered without sequelae after intravenous injection of methylprednisolone sodium succinate. The patient was not hospitalized and the event was categorized as non-serious. Eight additional non-serious events observed closely following iohexol injection were considered as not related to treatment. Thus, independent of disease conditions and GFR categories, the overall rate of treatment-related events was 0.0066%.

Conclusion: Iohexol administration for GFR measurement is a safe procedure, even in repeated investigations in the same subject, that should be adopted in clinical research and, when needed, also in clinical practice.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1159/000489898DOI Listing
September 2019

Blood Pressure and Metabolic Effects of Acetyl-l-Carnitine in Type 2 Diabetes: DIABASI Randomized Controlled Trial.

J Endocr Soc 2018 May 22;2(5):420-436. Epub 2018 Mar 22.

Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama.

Context: Acetyl-l-carnitine (ALC), a mitochondrial carrier involved in lipid oxidation and glucose metabolism, decreased systolic blood pressure (SBP), and ameliorated insulin sensitivity in hypertensive nondiabetic subjects at high cardiovascular risk.

Objective: To assess the effects of ALC on SBP and glycemic and lipid control in patients with hypertension, type 2 diabetes mellitus (T2D), and dyslipidemia on background statin therapy.

Design: After 4-week run-in period and stratification according to previous statin therapy, patients were randomized to 6-month, double-blind treatment with ALC or placebo added-on simvastatin.

Setting: Five diabetology units and one clinical research center in Italy.

Patients: Two hundred twenty-nine patients with hypertension and dyslipidemic T2D >40 years with stable background antihypertensive, hypoglycemic, and statin therapy and serum creatinine <1.5 mg/dL.

Interventions: Oral ALC 1000 mg or placebo twice daily on top of stable simvastatin therapy.

Outcome And Measures: Primary outcome was SBP. Secondary outcomes included lipid and glycemic profiles. Total-body glucose disposal rate and glomerular filtration rate were measured in subgroups by hyperinsulinemic-euglycemic clamp and iohexol plasma clearance, respectively.

Results: SBP did not significantly change after 6-month treatment with ALC compared with placebo (-2.09 mm Hg -3.57 mm Hg, = 0.9539). Serum cholesterol, triglycerides, and lipoprotein(a), as well as blood glucose, glycated hemoglobin, fasting insulin levels, homeostatic model assessment of insulin resistance index, glucose disposal rate, and glomerular filtration rate did not significantly differ between treatments. Adverse events were comparable between groups.

Conclusions: Six-month oral ALC supplementation did not affect blood pressure, lipid and glycemic control, insulin sensitivity and kidney function in hypertensive normoalbuminuric and microalbuminuric T2D patients on background statin therapy.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1210/js.2017-00426DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5912091PMC
May 2018

A Simple Method to Measure Renal Function in Swine by the Plasma Clearance of Iohexol.

Int J Mol Sci 2018 Jan 12;19(1). Epub 2018 Jan 12.

Instituto Tecnologías Biomédicas (ITB), University of La Laguna, 38320 Tenerife, Spain.

There is no simple method to measure glomerular filtration rate (GFR) in swine, an established model for studying renal disease. We developed a protocol to measure GFR in conscious swine by using the plasma clearance of iohexol. We used two groups, test and validation, with eight animals each. Ten milliliters of iohexol (6.47 g) was injected into the marginal auricular vein and blood samples (3 mL) were collected from the orbital sinus at different points after injection. GFR was determined using two models: two-compartment (CL2: all samples) and one-compartment (CL1: the last six samples). In the test group, CL1 overestimated CL2 by ~30%: CL2 = 245 ± 93 and CL1 = 308 ± 123 mL/min. This error was corrected by a first-order polynomial quadratic equation to CL1, which was considered the simplified method: SM = -47.909 + (1.176xCL1) - (0.00063968xCL1²). The SM showed narrow limits of agreement with CL2, a concordance correlation of 0.97, and a total deviation index of 14.73%. Similar results were obtained for the validation group. This protocol is reliable, reproducible, can be performed in conscious animals, uses a single dose of the marker, and requires a reduced number of samples, and avoids urine collection. Finally, it presents a significant improvement in animal welfare conditions and handling necessities in experimental trials.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/ijms19010232DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5796180PMC
January 2018

Iohexol plasma clearance simplified by dried blood spot testing.

Nephrol Dial Transplant 2018 09;33(9):1597-1603

Dermatology, Medicine and Psychiatry Department, Clinical Medicine Department, Instituto de Tecnologías Biomédicas (ITB), Faculty of Medicine, Universidad de La Laguna, Tenerife, Spain.

Background: Renal function can be estimated with formulas, which are inaccurate, or measured with gold standard methods, which are reliable but unpractical. We propose to simplify the plasma clearance of iohexol, a gold standard method to measure renal function, by dried blood spot (DBS) testing.

Methods: We compared glomerular filtration rate (GFR) values assessed by DBS and the reference plasma analysis technique. We tested in vitro the agreement between non-volumetric and volumetric DBS with the reference technique. Then, we performed a clinical validation in vivo between volumetric DBS and plasma analysis in 203 patients. The agreement was evaluated with the concordance correlation coefficient (CCC), the total deviation index (TDI) and the coverage probability. We defined acceptable agreement as a TDI <10%.

Results: In the in vitro studies, the non-volumetric DBS showed moderate agreement, TDI = 26.0%, while the volumetric method showed better but insufficient agreement, TDI = 13.0%, with the reference method in plasma. The non-volumetric DBS was rejected. To improve the agreement of the volumetric DBS, iopamidol was used as an internal standard. This method showed acceptable agreement, TDI = 9.0% with the analysis in plasma, and was selected as the definitive DBS method. In the in vivo studies, the agreement between the final DBS method and the reference technique was acceptable: TDI = 9.5%. This indicates that 90% of the GFR values ranged from -9.5% to + 9.5% compared with the reference method.

Conclusions: We simplified the plasma clearance of iohexol using DBS without losing accuracy and precision with respect to the reference technique. This may facilitate the use of a reliable determination of renal function to the medical community.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1093/ndt/gfx323DOI Listing
September 2018

Moderate salt restriction with or without paricalcitol in type 2 diabetes and losartan-resistant macroalbuminuria (PROCEED): a randomised, double-blind, placebo-controlled, crossover trial.

Lancet Diabetes Endocrinol 2018 01 2;6(1):27-40. Epub 2017 Nov 2.

Istituto di Ricovero e Cura a Carattere Scientifico-Istituto di Ricerche Farmacologiche Mario Negri, Centro Anna Maria Astori, Science and Technology Park Kilometro Rosso, Bergamo, Italy; Department of Medicine, Unit of Nephrology and Dialysis, Azienda Socio-Sanitaria Territoriale Papa Giovanni XXIII, Bergamo, Italy.

Background: Macroalbuminuria predicts renal and cardiovascular events in patients with type 2 diabetes. We aimed to assess the albuminuria-lowering effects of salt restriction, paricalcitol therapy, or both, in this population.

Methods: In this randomised, double-blind, placebo-controlled, crossover trial, we recruited adult patients with type 2 diabetes from six diabetology outpatient clinics in northern Italy, with 24 h albuminuria of more than 300 mg despite 100 mg per day losartan therapy, blood pressure of less than 140/90 mm Hg, serum creatinine concentration of less than 2 mg/dL, stable renal function on stable renin-angiotensin system inhibitor therapy with a fixed dose of losartan, parathyroid hormone concentration of 20 pg/mL to <110 pg/mL, serum calcium concentration of less than 9·5 mg/dL, and serum phosphate concentration of less than 5 mg/dL, who had been more than 80% compliant with placebo treatment during a 1 month placebo run-in. We allocated patients 1:1 with computer-generated randomisation to an open-label 3 month high-sodium (>200 mEq [4·8 g] per day) or low-sodium (<100 mEq [2·4 g] per day) diet and, within each diet group, to a 1 month double-blind treatment period of oral paricalcitol (2 μg per day) or placebo, followed by 1 month of placebo washout and then a further 1 month double-blind treatment period of paricalcitol or placebo in which patients crossed over to the opposite treatment period. The primary outcome was 24 h albuminuria (median of three consecutive measurements). Analyses were modified intention-to-treat (including all randomly allocated patients who took at least one dose of study drug and had an efficacy measurement after the first treatment period). Patients and investigators were masked to paricalcitol and placebo assignment. Those assessing outcomes were masked to both study drug and diet assignment. This study is registered with ClinicalTrials.gov, number NCT01393808, and the European Union Clinical Trials Register, number 2011-001713-14.

Findings: Between Dec 13, 2011, and Feb 17, 2015, we randomly allocated 57 (50%) patients to a low-sodium diet (28 [49%] to paricalcitol then placebo and 29 [51%] to placebo then paricalcitol) and 58 (50%) to a high-sodium diet (29 [50%] to paricalcitol then placebo and 29 [50%] to placebo then paricalcitol). In the low-sodium group (30 mEq of daily sodium intake reduction, equivalent to approximately 1·7-1·8 g per day), 24 h albuminuria was reduced by 36·6% (95% CI 28·5-44·9) from 724 mg (441-1233) at baseline to 481 mg (289-837) at month 3 (p<0·0001), but no significant change occurred in the high-sodium group (from 730 mg [416-1227] to 801 mg [441-1365]; 2·9% [-16·8 to 16·4] increase; p=0·50). Changes between diet groups differed by 32·4% (17·2-48·8; p<0·0001) and correlated with changes in natriuresis (r=0·43; p<0·0001). On the high-sodium diet, paricalcitol reduced the salt-induced albuminuria increase by 17·8% (3·9-32·3) over the month of treatment compared with placebo (p=0·02), whereas on the low-sodium diet, paricalcitol did not have a significant effect versus placebo (increase of 4·1% [-9·3 to 21·6]; p=0·59). During placebo treatment, albuminuria decreased with the low-sodium diet (p=0·0002) and did not significantly change with the high-sodium diet, but changes were significantly different between diet groups (p=0·0004). Treatment was well tolerated and no patients withdrew from the study because of treatment-related effects. 67 adverse events occurred in 52 (45%) patients during paricalcitol treatment and 44 events occurred in 36 (31%) patients during placebo treatment. During paricalcitol therapy, 14 cases of hypercalciuria, six cases of hypercalcaemia, and five cases of hyperphosphataemia were reported in one patient each, all of which were possibly treatment related. One case of hypercalciuria was reported in one patient during the placebo treatment period. One stroke and one coronary event occurred during paricalcitol therapy. No patients died during the study.

Interpretation: In patients with macroalbuminuria and type 2 diabetes, moderate salt restriction enhances the antialbuminuric effect of losartan, an effect that could be nephroprotective and cardioprotective in the long term. The finding that paricalcitol prevents a sodium-induced increase in albuminuria provides support for trials to test the long-term risk-benefit profile of paricalcitol add-on therapy in patients with type 2 diabetes and macroalbuminuria refractory to dietary salt restriction, including patients refractory to even moderate salt restriction.

Funding: AbbVie.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/S2213-8587(17)30359-5DOI Listing
January 2018

Conversion from Brand-Name Neoral to the Generic Ciqorin in Stable Renal Transplant Recipients.

Nephron 2017 10;135(3):173-180. Epub 2016 Dec 10.

Clinical Research Center for Rare Diseases Aldo and Cele Daccò, IRCCS - Istituto di Ricerche Farmacologiche Mario Negri, Bergamo, Italy.

Background/aims: Transplant physicians and patients are often reluctant to change to generic versions of immunosuppressive drugs with a narrow therapeutic index, such as ciclosporin (CsA). Thus, in routine follow-up for kidney transplant patients receiving CsA maintenance immunosuppressive therapy in our center, we evaluated the exchangeability of the brand name, Neoral, and the recently approved CsA generic formulation, Ciqorin.

Methods: We assessed the complete 12-h CsA pharmacokinetic profile and direct measurement of glomerular filtration rate (mGFR) of 10 patients receiving stable doses of Neoral (138 ± 43 mg/day), at least 6 months after kidney transplantation (Neoral 1). The same evaluations were repeated 10 days after conversion to Ciqorin on a milligram-to-milligram basis and 10 days after reinstituting Neoral (Neoral 2).

Results: The mean CsA area under the concentration-time curve increased slightly after switching from Neoral to Ciqorin (p = 0.03), but did not change significantly after Neoral was reintroduced (Neoral 1: 2,234 ± 783, Ciqorin: 2,452 ± 767, Neoral 2: 2,472 ± 784 ng × h/mL). There were no appreciable differences between the 2 CsA formulations in trough levels, maximum concentrations, or time to reach maximum concentrations. In all patients, renal function remained stable throughout the monitoring period (mGFR, Neoral 1: 52.0 ± 16.2; Ciqorin: 55.0 ± 19.0; Neoral 2: 55.8 ± 18.9 mL/min/1.73 m2), as did urinary and hematochemical parameters.

Conclusions: In stable kidney transplant recipients, switching from Neoral to Ciqorin resulted in similar pharmacokinetic parameters and did not change renal allograft function, reassuring physicians and patients regarding the exchangeability of reference and generic CsA formulations.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1159/000453671DOI Listing
March 2017

Iohexol plasma clearance for measuring glomerular filtration rate in clinical practice and research: a review. Part 2: Why to measure glomerular filtration rate with iohexol?

Clin Kidney J 2016 Oct 9;9(5):700-4. Epub 2016 Sep 9.

IRCCS - Istituto di Ricerche Farmacologiche 'Mario Negri', Centro di Ricerche Cliniche per le Malattie Rare 'Aldo e Cele Daccò', Ranica, Bergamo, Italy.

A reliable assessment of glomerular filtration rate (GFR) is of paramount importance in clinical practice as well as epidemiological and clinical research settings. It is recommended by Kidney Disease: Improving Global Outcomes guidelines in specific populations (anorectic, cirrhotic, obese, renal and non-renal transplant patients) where estimation equations are unreliable. Measured GFR is the only valuable test to confirm or confute the status of chronic kidney disease (CKD), to evaluate the slope of renal function decay over time, to assess the suitability of living kidney donors and for dosing of potentially toxic medication with a narrow therapeutic index. Abnormally elevated GFR or hyperfiltration in patients with diabetes or obesity can be correctly diagnosed only by measuring GFR. GFR measurement contributes to assessing the true CKD prevalence rate, avoiding discrepancies due to GFR estimation with different equations. Using measured GFR, successfully accomplished in large epidemiological studies, is the only way to study the potential link between decreased renal function and cardiovascular or total mortality, being sure that this association is not due to confounders, i.e. non-GFR determinants of biomarkers. In clinical research, it has been shown that measured GFR (or measured GFR slope) as a secondary endpoint as compared with estimated GFR detected subtle treatment effects and obtained these results with a comparatively smaller sample size than trials choosing estimated GFR. Measuring GFR by iohexol has several advantages: simplicity, low cost, stability and low interlaboratory variation. Iohexol plasma clearance represents the best chance for implementing a standardized GFR measurement protocol applicable worldwide both in clinical practice and in research.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5036903PMC
http://dx.doi.org/10.1093/ckj/sfw071DOI Listing
October 2016

Iohexol plasma clearance for measuring glomerular filtration rate in clinical practice and research: a review. Part 1: How to measure glomerular filtration rate with iohexol?

Clin Kidney J 2016 Oct 23;9(5):682-99. Epub 2016 Aug 23.

Department of Clinical Chemistry , Skåne University Hospital , Lund , Sweden.

While there is general agreement on the necessity to measure glomerular filtration rate (GFR) in many clinical situations, there is less agreement on the best method to achieve this purpose. As the gold standard method for GFR determination, urinary (or renal) clearance of inulin, fades into the background due to inconvenience and high cost, a diversity of filtration markers and protocols compete to replace it. In this review, we suggest that iohexol, a non-ionic contrast agent, is most suited to replace inulin as the marker of choice for GFR determination. Iohexol comes very close to fulfilling all requirements for an ideal GFR marker in terms of low extra-renal excretion, low protein binding and in being neither secreted nor reabsorbed by the kidney. In addition, iohexol is virtually non-toxic and carries a low cost. As iohexol is stable in plasma, administration and sample analysis can be separated in both space and time, allowing access to GFR determination across different settings. An external proficiency programme operated by Equalis AB, Sweden, exists for iohexol, facilitating interlaboratory comparison of results. Plasma clearance measurement is the protocol of choice as it combines a reliable GFR determination with convenience for the patient. Single-sample protocols dominate, but multiple-sample protocols may be more accurate in specific situations. In low GFRs one or more late samples should be included to improve accuracy. In patients with large oedema or ascites, urinary clearance protocols should be employed. In conclusion, plasma clearance of iohexol may well be the best candidate for a common GFR determination method.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5036902PMC
http://dx.doi.org/10.1093/ckj/sfw070DOI Listing
October 2016

Iohexol plasma clearance, a simple and reliable method to measure renal function in conscious mice.

Pflugers Arch 2016 09 17;468(9):1587-94. Epub 2016 Jun 17.

University of La Laguna, Instituto Tecnologías Biomédicas (ITB), Tenerife, Spain.

In mice, renal function evaluated by serum creatinine has limitations. Gold standard methods using radioactive markers are cumbersome. We aimed to develop the iohexol plasma clearance as a simple assessment of renal function in conscious mice. We used two groups of mice: testing and validation, formed by 16 animals (8 male and 8 female) each. Iohexol was injected intravenously into the tail vein (6.47 mg), and tail tip blood samples were collected at 1, 3, 7, 10, 15, 35, 55, and 75 min. Iohexol plasma clearances were calculated in two ways: (1) two-compartment model (CL2) using all time points and (2) one-compartment model (CL1) using only the last four points. In the testing group, CL1 overestimated the true clearance (CL2). Therefore, CL1 was recalculated applying a correction factor calculated as the ratio between CL2/CL1. The latter was considered as the simplified method. CL2 averaged 223.3 ± 64.3 μl/min and CL1 252.4 ± 76.4 μl/min, which lead to a CF of 0.89. Comparable results for CL2, CL1, and simplified method were observed in the validation group. Additionally, we demonstrated the capacity of the simplified method to quantitatively assess different degrees of renal function in three mouse models: hyperoxaluric-CKD (87.4 ± 28.3 μl/min), heminephrectomized (135-0 ± 50.5 μl/min), and obese (399.6 ± 112.1 μl/min) mice. We have developed a simple and reliable method to evaluate renal function in conscious mice under diverse clinical conditions. Moreover, the test can be repeated in the same animal, which makes the method useful to examine renal function changes over time.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s00424-016-1843-4DOI Listing
September 2016

Simplified Method to Measure Glomerular Filtration Rate by Iohexol Plasma Clearance in Conscious Rats.

Nephron 2016 4;133(1):62-70. Epub 2016 May 4.

Clinical Research Center for Rare Diseases x2018;Aldo and Cele Daccx00F2;', IRCCS - Istituto di Ricerche Farmacologiche Mario Negri, Bergamo, Italy.

Background/aims: Glomerular filtration rate (GFR) is the best index for evaluating renal function. We aimed to develop a simplified iohexol plasma clearance procedure for GFR measurement in rats without urine collection, animal catheterization or anesthesia, with limited sampling and requiring blood instead of plasma, to further reduce the sample volume and improve animal welfare.

Methods: After iohexol injection (129.4 mg), samples were drawn according to 2-compartment kinetics and analyzed by high performance liquid chromatography. Healthy male Lewis rats were used to find a correction factor (CF) to obtain the 'reference clearance' from the simplified 1-comparment model. This approach was validated using male or female (Lewis, Sprague-Dawley) rats and animals with renal mass reduction (RMR). In additional rats, different simplified approaches were evaluated.

Results: Iohexol concentrations in blood and plasma strongly correlated (r = 0.9784, p < 0.0001). A CF of 0.90 enabled the calculation of the reference GFR. Validation results in male Lewis rats were 0.99 ± 0.27 for the reference GFR and 1.03 ± 0.29 ml/min/100 g for the simplified approach. Results in female Sprague-Dawley rats confirmed the suitability of the proposed method. In RMR rats, GFR was 0.14 ± 0.05 and 0.14 ± 0.04 ml/min/100 g for the reference and simplified model, respectively.

Conclusion: The procedure we set up to measure GFR in conscious rats was proven to be reliable, required a small volume of blood at only 4 selected time points, without the need to collect urine or catheterize the animals, was applicable to rats from different strains and sexes, both healthy and with renal function impairment. Moreover, the procedure enables the monitoring of GFR changes over time in the same animal, thereby reducing the number of animals to be used.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1159/000445843DOI Listing
February 2017

Effect of Sirolimus on Disease Progression in Patients with Autosomal Dominant Polycystic Kidney Disease and CKD Stages 3b-4.

Clin J Am Soc Nephrol 2016 05 22;11(5):785-94. Epub 2016 Feb 22.

Clinical Research Center for Rare Diseases "Aldo e Cele Daccò," IRCCS-Istituto di Ricerche Farmacologiche "Mario Negri," Bergamo, Italy; Units of Nephrology and Dialysis, Department of Biomedical and Clinical Sciences, University of Milan, Milan, Italy

Background And Objectives: The effect of mammalian target of rapamycin (mTOR) inhibitors has never been tested in patients with autosomal dominant polycystic kidney disease (ADPKD) and severe renal insufficiency.

Design, Setting, Participants, & Measurements: In this academic, prospective, randomized, open label, blinded end point, parallel group trial (ClinicalTrials.gov no. NCT01223755), 41 adults with ADPKD, CKD stage 3b or 4, and proteinuria ≤0.5 g/24 h were randomized between September of 2010 and March of 2012 to sirolimus (3 mg/d; serum target levels of 5-10 ng/ml) added on to conventional therapy (n=21) or conventional treatment alone (n=20). Primary outcome was GFR (iohexol plasma clearance) change at 1 and 3 years versus baseline.

Results: At the 1-year preplanned interim analysis, GFR fell from 26.7±5.8 to 21.3±6.3 ml/min per 1.73 m(2) (P<0.001) and from 29.6±5.6 to 24.9±6.2 ml/min per 1.73 m(2) (P<0.001) in the sirolimus and conventional treatment groups, respectively. Albuminuria (73.8±81.8 versus 154.9±152.9 μg/min; P=0.02) and proteinuria (0.3±0.2 versus 06±0.4 g/24 h; P<0.01) increased with sirolimus. Seven patients on sirolimus versus one control had de novo proteinuria (P=0.04), ten versus three patients doubled proteinuria (P=0.02), 18 versus 11 patients had peripheral edema (P=0.04), and 14 versus six patients had upper respiratory tract infections (P=0.03). Three patients on sirolimus had angioedema, 14 patients had aphthous stomatitis, and seven patients had acne (P<0.01 for both versus controls). Two patients progressed to ESRD, and two patients withdrew because of worsening of proteinuria. These events were not observed in controls. Thus, the independent data and safety monitoring board recommend early trial termination for safety reasons. At 1 year, total kidney volume (assessed by contrast-enhanced computed tomography imaging) increased by 9.0% from 2857.7±1447.3 to 3094.6±1519.5 ml on sirolimus and 4.3% from 3123.4±1695.3 to 3222.6±1651.4 ml on conventional therapy (P=0.12). On follow-up, 37% and 7% of serum sirolimus levels fell below or exceeded the therapeutic range, respectively.

Conclusions: Finding that sirolimus was unsafe and ineffective in patients with ADPKD and renal insufficiency suggests that mTOR inhibitor therapy may be contraindicated in this context.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.2215/CJN.09900915DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4858487PMC
May 2016

Estimated Glomerular Filtration Rate in Renal Transplantation: The Nephrologist in the Mist.

Transplantation 2015 Dec;99(12):2625-33

1 Centre for Biomedical Research of the Canary Islands (CIBICAN). University of La Laguna, Tenerife, Spain. 2 Department of Nephrology, University Hospital of the Canary Islands, Tenerife, Spain. 3 Department of Anatomic Pathology, Faculty of Medicine at the University of La Laguna, Tenerife, Spain. 4 Department of Clinical Pharmacology, University Hospital of the Canary Islands, Tenerife, Spain. 5 Istituto di Ricerche Farmacologiche Mario Negri, Clinical Research Center for Rare Diseases "Aldo e Cele Daccò", Ranica (BG), Italy. 6 Clinical Analysis Laboratory, University Hospital Marqués de Valdecilla, Santander, Spain. 7 Fundación Canaria Rafael Clavijo para la Investigación Biomédica, Tenerife, Spain. 8 Research Unit, University Hospital of the Canary Islands, Tenerife, Spain.

Background: Formulas do not estimate renal function with acceptable precision and accuracy.

Methods: We compared 51 creatinine-based and/or cystatin c-based formulas with a gold standard (iohexol plasma clearance) in 193 renal transplant recipients using concordance correlation coefficient, total deviation index, coverage probability and the error in chronic kidney disease (CKD) stage classification.

Results: No formula showed a concordance correlation coefficient greater than 0.90 (average for creatinine-based formulas: ∼0.70 and for cystatin c-based formulas: ∼0.85). A wide total deviation index was observed: approximately 70% (creatinine-based) and approximately 50% (cystatin c-based), indicating that 90% of the estimations showed bounds of error of ±70% or ±50%, respectively, compared with the gold standard. No formula included 90% of the estimations within a coverage probability of ±10%. Half the CKD stages classified by creatinine-based formulas were incorrect, mainly due to overestimation of renal function. One of 3 CKD stages diagnosed by cystatin c-based formulas was incorrect, with both overestimation and underestimation. Overall, the formulas showed very low precision and accuracy and a high degree of error in reflecting real renal function.

Conclusions: In conclusion, formulas do not properly reflect renal function in kidney transplantation, which makes their use in clinical practice unreliable. Moreover, their use in clinical trials should be avoided.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1097/TP.0000000000000786DOI Listing
December 2015

A multidrug, antiproteinuric approach to alport syndrome: a ten-year cohort study.

Nephron 2015 21;130(1):13-20. Epub 2015 Apr 21.

IRCCS - Istituto di Ricerche Farmacologiche "Mario Negri", Clinical Research Centre for Rare Diseases "Aldo & Cele Daccò", Bergamo, Italy.

Background/aims: Combined ACE inhibitor, angiotensin-receptor-blocker, non-dihydropyridine calcium-channel-blocker, and statin therapy (Remission Clinic) reduced proteinuria and halted progression in non-diabetic nephropathies, but their efficacy in Alport syndrome (AS) nephropathy is unknown.

Methods: From February 2004 to September 2007, we included nine albuminuric AS adults with creatinine clearance >20 ml/min/1.73 m(2) in a single-center, open-label, prospective, off-on-off academic study. After the 1-month wash-out from RAS inhibition (Run-in), patients entered the 4-month, add-on, treatment period with benazepril (10-20 mg/day), valsartan (80-160 mg/day), diltiazem (60-120 mg/day), and fluvastatin (40-80 mg/day) followed by the 1-month wash-out (Recovery). The primary outcome was albuminuria at month 4. After recovery, patients were kept on the Remission Clinic protocol and followed until July 2014 (Extension).

Results: The median (IQR) albuminuria progressively declined from 657.7 (292.7-1,089.6) μg/min at baseline to 71.4 (21.7-504.9) μg/min at treatment end (p = 0.009) and raised to 404.3 (167.9-446.8) μg/min after recovery. Albumin and IgG fractional clearances significantly (p ≤ 0.005) decreased from 66.9 (53.6-80.8) to 9.4 (4.6-26.0) and from 5.1 (3.0-8.4) to 1.1 (0.6-3.2), and then recovered toward baseline. Blood pressure and lipids significantly decreased on treatment, without changes in inulin-measured GFR or para-aminohippuric-measured RPF. After recovery, one patient refused to enter the extension, one with severe renal insufficiency at baseline reached ESRD, and seven retained normal serum creatinine until the end of the study. At the final visit, three were microalbuminuric and one was normoalbuminuric. Treatment was well tolerated.

Conclusion: The Remission Clinic approach safely ameliorated albuminuria, blood pressure, lipids, and glomerular selectivity in AS patients and halted long-term progression in those without renal insufficiency to start with.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1159/000381480DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4451141PMC
February 2016

Copeptin levels are associated with organ dysfunction and death in the intensive care unit after out-of-hospital cardiac arrest.

Crit Care 2015 Mar 31;19:132. Epub 2015 Mar 31.

Division of Intensive Care Medicine, Department of Anaesthesiology, Intensive Care and Pain Medicine, University of Helsinki and Helsinki University Hospital, Haartmaninkatu 4, 00290, Helsinki, Finland.

Introduction: We studied associations of the stress hormones copeptin and cortisol with outcome and organ dysfunction after out-of-hospital cardiac arrest (OHCA).

Methods: Plasma was obtained after consent from next of kin in the FINNRESUSCI study conducted in 21 Finnish intensive care units (ICUs) between 2010 and 2011. We measured plasma copeptin (pmol/L) and free cortisol (nmol/L) on ICU admission (245 patients) and at 48 hours (additional 33 patients). Organ dysfunction was categorised with 24-hour Sequential Organ Failure Assessment (SOFA) scores. Twelve-month neurological outcome (available in 276 patients) was classified with cerebral performance categories (CPC) and dichotomised into good (CPC 1 or 2) or poor (CPC 3 to 5). Data are presented as medians and interquartile ranges (IQRs). A Mann-Whitney U test, multiple linear and logistic regression tests with odds ratios (ORs) 95% confidence intervals (CIs) and beta (B) values, repeated measure analysis of variance, and receiver operating characteristic curves with area under the curve (AUC) were performed.

Results: Patients with a poor 12-month outcome had higher levels of admission copeptin (89, IQR 41 to 193 versus 51, IQR 29 to 111 pmol/L, P = 0.0014) and cortisol (728, IQR 522 to 1,017 versus 576, IQR 355 to 850 nmol/L, P = 0.0013). Copeptin levels fell between admission and 48 hours (P <0.001), independently of outcome (P = 0.847). Cortisol levels did not change between admission and 48 hours (P = 0.313), independently of outcome (P = 0.221). The AUC for predicting long-term outcome was weak for copeptin (0.62, 95% CI 0.55 to 0.69) and cortisol (0.62, 95% CI 0.54 to 0.69). With logistic regression, admission copeptin (standard deviation (SD) increase OR 1.4, 95% CI 1.03 to 1.98) and cortisol (SD increase OR 1.5, 95% CI 1.1 to 2.0) predicted ICU mortality but not 12-month outcome. Admission factors correlating with SOFA were shockable rhythm (B -1.3, 95% CI -2.2 to -0.5), adrenaline use (B 1.1, 95% CI 0.2 to 2.0), therapeutic hypothermia (B 1.3 95% CI 0.4-2.2), and copeptin (B 0.04, 95% CI 0.02 to 0.07).

Conclusions: Admission copeptin and free cortisol were not of prognostic value regarding 12-month neurological outcome after OHCA. Higher admission copeptin and cortisol were associated with ICU death, and copeptin predicted subsequent organ dysfunction.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1186/s13054-015-0831-yDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4415235PMC
March 2015
-->