Yves Vanrenterghem

Bio: Yves Vanrenterghem is an academic researcher from Katholieke Universiteit Leuven. The author has contributed to research in topics: Transplantation & Kidney transplantation. The author has an hindex of 79, co-authored 403 publications receiving 22451 citations. Previous affiliations of Yves Vanrenterghem include Rega Institute for Medical Research & Leiden University.

Reduced exposure to calcineurin inhibitors in renal transplantation.

Abstract: Background Immunosuppressive regimens with the fewest possible toxic effects are desirable for transplant recipients. This study evaluated the efficacy and relative toxic effects of four immunosuppressive regimens. Methods We randomly assigned 1645 renal-transplant recipients to receive standard-dose cyclosporine, mycophenolate mofetil, and corticosteroids, or daclizumab induction, mycophenolate mofetil, and corticosteroids in combination with low-dose cyclosporine, low-dose tacrolimus, or low-dose sirolimus. The primary end point was the estimated glomerular filtration rate (GFR), as calculated by the Cockcroft–Gault formula, 12 months after transplantation. Secondary end points included acute rejection and allograft survival. Results The mean calculated GFR was higher in patients receiving low-dose tacrolimus (65.4 ml per minute) than in the other three groups (range, 56.7 to 59.4 ml per minute). The rate of biopsy-proven acute rejection was lower in patients receiving low-dose tacrolimus (12.3%) than i...

A randomized double-blind, multicenter plasma concentration controlled study of the safety and efficacy of oral mycophenolate mofetil for the prevention of acute rejection after kidney transplantation.

Abstract: Background. Adding a fixed dose of 1 g b.i.d. of mycophenolate mofetil (MMF) to an immunosuppressive regimen consisting of cyclosporine and prednisone results in a 50% reduction in the incidence of acute rejection after kidney transplantation. This study was designed to investigate the relationship between pharmacokinetic data (mycophenolic acid area under the curve; MPA AUC) and the prevention of rejection after kidney transplantation. Methods. A total of 154 adult recipients of a primary or secondary cadaveric kidney graft were randomly allocated, in this double-blind trial, to receive MMF treatment aimed at three predefined target MPA AUC values (16.1, 32.2, and 60.6 μg-hr/ml). During the first 6 months after transplantation, plasma samples for nine AUCs were collected. After analysis of the samples, a coded dose adjustment advice was generated using a Bayesian algorithm, maintaining the double blinding. Immunosuppressive therapy further consisted of cyclosporine and prednisone. The primary end point of this study was the occurrence of biopsy-proven acute rejection within the 6-month study period. Results. A total of 150 patients were eligible for analysis. Although after day 21, the mean MMF dose was reduced, the mean MPA AUC gradually increased and target MPA AUC values were exceeded in all three groups. The incidences of biopsy-proven acute rejection in the low, intermediate, and high target MPA AUC groups were 14 of 51 (27.5%), 7 of 47 (14.9%), and 6 of 52 (11.5%), respectively. The incidences of premature withdrawal from the study due to adverse events in the three groups were 4 of 51 (7.8%), 11 of 47 (23.4%), and 23 of 52 (44.2%), respectively. Logistic regression analysis showed a highly statistically significant relationship between median ln(MPA AUC) and the occurrence of a biopsy-proven rejection (P<0.001). The logistic regression using median In(C predose ) was also statistically significant for this relationship (P=0.01), whereas it was not when using mean MMF dose (P=0.082). In contrast, the logistic regression using mean MMF dose for comparison of patients who successfully completed the study versus patients experiencing premature withdrawal due to adverse events was highly significant (P<0.001), whereas this was not significant when using median In(C predose ) (P=0.512) or median In(MPA AUC) (P=0.434). Conclusion. MPA C predose and MPA AUC are significantly related to the incidence of biopsy-proven rejection after kidney transplantation, whereas MMF dose is significantly related to the occurrence of adverse events.

The pharmacokinetic‐pharmacodynamic relationship for mycophenolate mofetil in renal transplantation

Abstract: Background: Mycophenolate mofetil, a pro-drug for mycophenolic acid, reduces the likelihood of allograft rejection after renal transplantation. We studied the relationship between mycophenolic acid pharmacokinetics and the likelihood of rejection in a randomized concentration-controlled trial. Methods: Under double-blind conditions, recipients of kidney transplants were followed for evidence of allograft rejection for 6 months. In addition to mycophenolate mofetil, patients received usual doses of cyclosporine (INN, ciclosporin) and corticosteroids, The dose of mycophenolate mofetil (given twice daily) was controlled by feedback, with mycophenolic acid area under the concentration-time curve (AUC) as the controlled variable. Patients were randomly assigned to 1 of 3 target AUC groups. Results: Logistic regression analysis showed a significant (P < .0001) relationship between mycophenolic acid AUC and the likelihood of rejection. High mycophenolic acid values were associated with a very low probability of rejection. An AUC of 15 mu g.h/mL yielded 50% of maximal achievable efficacy with a 4% change of efficacy for a 1 mu g.h/mL change in AUC at the midpoint of the logistic curve. Exploratory analyses showed other variables (eg, the maximum observed plasma concentration, predose plasma concentration, and drug dose) had poorer predictive power for the rejection outcome. Bivariate regression confirmed the importance of AUC as a highly predictive variable and showed low predictive value of other variables, once the contribution of AUC had been considered. The characteristic side effects of mycophenolate mofetil therapy appeared related to drug dose but not to mycophenolic acid concentration. Conclusions The AUC of mycophenolic acid is predictive of the likelihood of allograft rejection after renal transplantation in patients receiving mycophenolate mofetil.

Health promotion from the perspective of social cognitive theory

Abstract: This article examines health promotion and disease prevention from the perspective of social cognitive theory. The areas of overlap with some of the most widely applied psychosocial models of health are identified. The models of health promotion and disease prevention have undergone several generational changes. We have shifted from trying to scare people into health, to rewarding them into health, to equipping them with self-regulatory skills to manage their health habits, to shoring up their habit changes with dependable social supports. These transformations have evolved a multifaceted approach that addresses the reciprocal interplay between self-regulatory and environmental determinants of health behavior. Social cognitive theory addresses the socio structural determinants of health as well as the personal determinants. A comprehensive approach to health promotion requires changing the practices of social systems that have widespread detrimental effects on health rather than solely changing t...

Gut microbiota, metabolites and host immunity

Abstract: The microbiota - the collection of microorganisms that live within and on all mammals - provides crucial signals for the development and function of the immune system. Increased availability of technologies that profile microbial communities is facilitating the entry of many immunologists into the evolving field of host-microbiota studies. The microbial communities, their metabolites and components are not only necessary for immune homeostasis, they also influence the susceptibility of the host to many immune-mediated diseases and disorders. In this Review, we discuss technological and computational approaches for investigating the microbiome, as well as recent advances in our understanding of host immunity and microbial mutualism with a focus on specific microbial metabolites, bacterial components and the immune system.