Adult Renal Transplant Patients (adult + renal_transplant_patient)

Distribution by Scientific Domains


Selected Abstracts


Does peak systolic velocity correlate with renal artery stenosis in a pediatric renal transplant population?

PEDIATRIC TRANSPLANTATION, Issue 5 2006
Anthony Cook
Abstract:, PSV of renal transplant vessels, calculated during allograft ultrasonography, has previously been shown to correlate with TRAS. Controversy exists regarding the threshold PSV value (adult range: 1.5,3.0 ms), which should prompt further, more invasive investigations to confirm the diagnosis of TRAS. Furthermore, there is a paucity of literature regarding PSV values in the pediatric renal transplant population. In a group of pediatric renal transplant patients, we correlated post-operative renal transplant PSV values with BP, renal function (serum creatinine) and TRAS. All patients who underwent cadaveric or living-related renal transplantation at the HSC between 2001 and 2004 with at least 6 months of follow-up were reviewed through the HSC multi-organ transplant database. Post-operative allograft Doppler ultrasonography was performed during routine follow-up. PSV values obtained were correlated with BP and serum creatinine performed concomitantly. Finally, we correlated PSV in those patients who underwent more intensive investigations, including magnetic resonance and conventional angiography. Fifty-three patients underwent transplantation during the study period. Complete data available for 50/53 demonstrated a mean PSV of 2.13 m/s (range: 0.9,6.1 m/s) for all patients. Of six patients who underwent MRA for suspicion of TRAS, two (with mean PSV values of 1.93 m/s) were found to have clinically significant stenoses. Four of six without angiographic evidence of TRAS had mean PSV values of 2.22 m/s. Patients suspected of having TRAS demonstrated elevated median serum creatinine values compared with those without clinical suspicion of TRAS. However, both mean PSV and BP were not found to be statistically different in both patient subgroups. Furthermore, there was no correlation identified between PSV and serum creatinine and BP in these patient populations. Despite the utility of PSV for monitoring adult renal transplant patients, we did not find that PSV correlated with BP, nadir creatinine or identify those patients who, through subsequent investigations, were found to have TRAS in this pediatric population. Maintaining cognizance in conjunction with close clinical follow-up may identify patients at risk for this rare but potentially morbid complication of transplantation. [source]


Population pharmacokinetics of sirolimus in de novo Chinese adult renal transplant patients

BRITISH JOURNAL OF CLINICAL PHARMACOLOGY, Issue 1 2009
Zheng Jiao
WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT? , Sirolimus is an immunosuppressive agent used for the prophylaxis of renal allograft rejection. , Several conventional pharmacokinetic and population pharmacokinetic studies have been conducted to assess the pharmacokinetic characteristics of sirolimus in White or African-American recipients. WHAT THIS STUDY ADDS? , The population pharmacokinetics of sirolimus in Chinese adult renal transplant recipients was characterized for the first time. , New drug,drug interactions between herbal medicines and sirolimus were identified as the covariates on sirolimus clearance. AIMS This study was aimed at determining the population pharmacokinetics of sirolimus and identifying factors that explain pharmacokinetic variability in de novo Chinese adult renal transplant patients. METHODS Data were retrospectively extracted from a formal multicentre clinical trial, which was originally designed to evaluate the safety and efficacy of ciclosporin dose reduction and ciclosporin elimination in patients receiving sirolimus. All patients received 12-month treatment, i.e. induction therapy with ciclosporin, sirolimus and corticosteroids during the first 3 months followed by either ciclosporin dose reduction or ciclosporin discontinuation thereafter. Eight-hundred and four sirolimus trough blood concentrations (C0) from 112 patients were used to develop a population pharmacokinetic model using the nonmem program. A one-compartment model with first-order absorption and elimination was selected as the base model. The influence of demographic characteristics, biochemical and haematological indices, ciclosporin daily dose, ciclosporin C0 as well as other commonly used co-medications were explored. RESULTS The typical values with interindividual variability for apparent clearance (CL/F) and apparent volume of distribution (V/F) were 10.1 l h,1 (23.8%) and 3670 l (56.7%), respectively. The residual variability was 29.9%. CL/F decreased significantly with silymarin or glycyrrhizin co-therapy in hepatically impaired patients, and with increasing total cholesterol levels or ciclosporin C0. Moreover, CL/F increased nonlinearly with increasing sirolimus daily dose. The median parameter estimates from a nonparametric bootstrap procedure were comparable and within 5% of the estimates from nonmem. CONCLUSIONS These results provide important information for clinicians to optimize sirolimus regimens in Chinese renal transplant patients. [source]


Establishing pediatric immune response zones using the Cylex® ImmuKnowTM assay

CLINICAL TRANSPLANTATION, Issue 6 2005
E Hooper
Abstract:, For all transplant patients, the transplant physician must balance the risk of rejection caused by under-immunosuppression against the risk of drug toxicity, secondary infections and post-transplant lymphoproliferative disorder with over-immunosuppression. A Food and Drug Administration (FDA)-approved in vitro assay, the Cylex® ImmuKnowTM assay, provides a global assessment of cellular immune function to help monitor the immune status of immunosuppressed patients. This assay uses the plant lectin phytohemagglutinin to stimulate lymphocytes; an ATP assay is then used to measure the degree of activation of CD4+ T cells. However, the normal values for this assay were developed with healthy adult patients. In this study, we determined the normal ranges for the ImmuKnowTM assay in healthy children and compared those values to levels obtained in healthy adults and in stable pediatric renal transplant patients. We found that healthy children 12 yr of age and older showed immune function levels indistinguishable from adults, while healthy children under 12 had significantly lower immune function levels than adults. For adults, the ImmuKnowTM assay zones (in ng/mL ATP) of strong, moderate and low immune function correspond to >525, 225 to 525, and <225. In children under 12, we found the corresponding zones to be >395, 175,395 and <175 ng/mL. The median value for normal adults is 415, whereas it is only 295 for children <12 yr of age and this value decreases to 165 in stable renal transplant patients <12 yr of age (compared with 258 for stable adult renal transplant patients). Thus, this study provides critical information necessary to utilize the ImmuKnowTM assay with pediatric patients. In adults, the degree of immune function as assessed by the ImmuKnowTM assay helps to predict patients at risk for infection or rejection. If further studies in pediatric patients document the same and is true for children, then the ImmuKnowTM assay will provide a useful adjunct tool to prevent over- or under-immunosuppression as newly developed drugs are utilized or drug treatment is altered because of drug side effects, toxicity, concurrent illnesses or rejection. [source]