Effect of high-dose erythropoietin on graft function after kidney transplantation: a meta-analysis of randomized controlled trials

Anemia after kidney transplantation

Anemia is a frequent complication in pediatric kidney transplant recipients (KTR) with a variable reported prevalence estimated between 20 and 80% depending on how defined. Causes of and risk factors for post-transplantation anemia (PTA) are multifactorial with iron deficiency being the primary cause of early PTA (within the first 6 months after transplantation) and impaired glomerular filtration rate (GFR) commonly responsible for late PTA (after 6 months). Medications, viral infections, chronic inflammation, and comorbidities also play a role. PTA has relevant long-term consequences and is a potential risk factor for allograft dysfunction, cardiovascular morbidity, and mortality. Thus, an anemia evaluation, approximately 3 months post-transplantation, is recommended in order to start early treatment and improve prognosis. Iron status, vitamin B12, folate, markers of hemolysis, and viral PCR should be checked, and medications, in particular combinations of medications, should be carefully evaluated. PTA treatment may be challenging and should be directed to the underlying causes. Iron supplementation and erythropoietin therapy, not extensively used in KTR, may be indicated. Every effort should be made to avoid blood transfusions in the pre-transplant period to avoid allosensitization. Anemia should be corrected to prepare candidates for kidney transplantation in order to reduce the need for perioperative blood transfusions as well.

Co-treatment with Esculin and erythropoietin protects against renal ischemia-reperfusion injury via P2X7 receptor inhibition and PI3K/Akt activation

Renal ischemia/reperfusion (RI/R) is a critical clinical outcome with slightly reported improvement in mortality and morbidity. Effective therapies are still crucially required. Accordingly, the therapeutic effects of esculin (ESC, LCESI-MS/MS-isolated compound from Vachellia farnesiana flowers extract, with reported P2X7 receptor inhibitor activity) alone and in combination with erythropoietin (EPO) were investigated against RI/R injury and the possible underlying mechanisms were delineated. ESC and EPO were administered for 7 days and 30 min prior to RI, respectively. Twenty-four hour following reperfusion, blood and kidney samples were collected. Results revealed that pretreatment with either ESC or EPO reduced serum nephrotoxicity indices, renal oxidative stress, inflammatory, and apoptosis markers. They also ameliorated the renal histopathological injury on both endothelial and tubular epithelial levels. Notably, ESC markedly inhibited P2X7 receptors and NLRP3 inflammasome signaling (downregulated NLRP3 and Caspase-1 gene expressions), whereas EPO significantly upregulated PI3K and Akt gene expressions, also p-PI3K and p-Akt levels in renal tissues. ESC, for the first time, demonstrated effective protection against RI/R-injury and its combination with EPO exerted maximal renoprotection when compared to each monotherapy, thereby representing an effective therapeutic approach via inhibiting oxidative stress, inflammation, renal tubular and endothelial injury, apoptosis, and P2X7 receptors expression, and activating PI3K/Akt pathway.

Intracochlear New Fibro-Ossification and Neuronal Degeneration Following Cochlear Implant Electrode Translocation: Long-Term Histopathological Findings in Humans

OBJECTIVE

We aim to assess the histopathology of human temporal bones (TBs) with evidence of cochlear implantation (CI) electrode scalar translocation.

STUDY DESIGN

Otopathology study.

SETTING

Otopathology laboratory.

PATIENTS

TBs from patients who had a history of CI and histopathological evidence of interscalar translocation. Specimens with electrode placed entirely within the ST served as controls.

INTERVENTION

Histopathological assessment of human TBs.

MAIN OUTCOME MEASURES

TBs from each patient were harvested postmortem and histologically analyzed for intracochlear changes in the context of CI electrode translocation and compared to controls. Intracochlear new fibro-ossification, and spiral ganglion neuron (SGN) counts were assessed. Postoperative word recognition scores (WRS) were also compared.

RESULTS

Nineteen human TBs with electrode translocation and eight controls were identified. The most common site of translocation was the ascending limb of the basal turn (n = 14 TBs). The average angle of insertion at the point of translocation was 159° ± 79°. Eighteen translocated cases presented moderate fibroosseous changes in the basal region of the cochlea, extending to the translocation point and/or throughout the electrode track in 42%. Lower SGN counts were more pronounced in translocated cases compared to controls, with a significant difference for segment II (p = 0.019). Although final postoperative hearing outcomes were similar between groups, translocated cases had slower rate of improvement in WRS (p = 0.021).

CONCLUSIONS

Cochlear implant electrode translocation was associated with greater fibroosseous formation and lower SGN population. Our findings suggest that scalar translocations may slow the rate of improvement in WRS overtime as compared to atraumatic electrode insertions.Level of evidence: IV.

Anemia in Pediatric Kidney Transplant Recipients-Etiologies and Management

Posttransplant anemia (PTA) is a common complication of pediatric kidney transplantation, with a prevalence ranging from 22 to 85%. PTA is categorized as early (within 6 months posttransplant) and late (>6 months posttransplant). Early PTA is typically associated with surgical blood losses and iron deficiency. Late PTA primarily results from graft dysfunction; however, iron deficiency, drug toxicity, and posttransplant inflammation also play a role. PTA is more severe compared with the anemia in glomerular-filtration-rate matched patients with native chronic kidney disease. Treatment of PTA is directed toward the underlying cause. Erythropoiesis stimulating agents (ESA) are effective; however, their use is limited in the transplant setting. Timely diagnosis and treatment of PTA are vital to prevent long-term adverse outcomes in pediatric transplant recipients.

Limited Clinical Utility of Remote Ischemic Conditioning in Renal Transplantation: A Meta-Analysis of Randomized Controlled Trials

OBJECTIVE

We conducted this meta-analysis of randomized controlled trials (RCTs) to investigate whether remote ischemic conditioning (RIC) could improve graft functions in kidney transplantation.

METHODS

PubMed, Web of Science, and Cochrane Library were comprehensively searched to identify all eligible studies by October 5, 2016. The treatment effects were examined with risk ratio (RR) and weighted mean difference with the corresponding 95% confidence intervals (CI). The statistical significance and heterogeneity were assessed with both Z-test and Q-test.

RESULTS

A total of six RCTs including 651 recipients, were eventually identified. Compared to the controls, RIC could reduce the incidence of delayed graft function (DGF) after kidney transplantation (random-effects model: RR = 0.89; fixed-effect model: RR = 0.84). However, the decrease did not reveal statistical significance. The subgroup analysis by RIC type demonstrated no significant difference among the three interventions in protecting renal allografts against DGF. Furthermore, no significant difference could be observed in the incidence of acute rejection, graft loss, 50% fall in serum creatinine, as well as the estimated glomerular filtration rate and hospital stay between the RIC and Control groups.

CONCLUSIONS

This meta-analysis suggested that RIC might exert renoprotective functions in human kidney transplantation, and further well-designed RCTs with large sample size are warranted to assess its clinical efficacy.

Improving the outcome of kidney transplantation by ameliorating renal ischemia reperfusion injury: lost in translation?

Kidney transplantation is the treatment of choice in patients with end stage renal disease. During kidney transplantation ischemia reperfusion injury (IRI) occurs, which is a risk factor for acute kidney injury, delayed graft function and acute and chronic rejection. Kidneys from living donors show a superior short- and long-term graft survival compared with deceased donors. However, the shortage of donor kidneys has resulted in expansion of the donor pool by using not only living- and brain death donors but also kidneys from donation after circulatory death and from extended criteria donors. These grafts are associated with an increased sensitivity to IRI and decreased graft outcome due to prolonged ischemia and donor comorbidity. Therefore, preventing or ameliorating IRI may improve graft survival. Animal experiments focus on understanding the mechanism behind IRI and try to find methods to minimize IRI either before, during or after ischemia. This review evaluates the different experimental strategies that have been investigated to prevent or ameliorate renal IRI. In addition, we review the current state of translation to the clinical setting. Experimental research has contributed to the development of strategies to prevent or ameliorate IRI, but promising results in animal studies have not yet been successfully translated to clinical use.