The Ultrasound Renal Stress Test for the Assessment of Functional Renal Reserve in Kidney Transplantation: A Pilot Study in Living Donors.

In the evolving landscape of nephrology and kidney transplants, assessing renal functional reserve (RFR) in living kidney donors is essential for ensuring donor safety and successful transplantation. This study explores the use of the Intra-Parenchymal Renal Resistive Index Variation (IRRIV) test, a novel non-invasive method, to measure RFR in living donors. Our observational study included 11 participants undergoing living kidney donations, evaluated using the IRRIV-based Renal Stress Test (RST) before and 12 months post-nephrectomy. The study demonstrated significant changes in creatinine and eGFR CKD-EPI levels post-donation, with an average creatinine rise from 69 to 97 µmol/L and a reduction in eGFR from 104 to 66 mL/min/1.73 m2. These variations align with the expected halving of nephron mass post-nephrectomy and the consequent recruitment of RFR and hyperfiltration in the remaining nephrons. This pilot study suggests that the IRRIV-based RST is a practical, safe, and reproducible tool, potentially revolutionizing the assessment of RFR in living kidney donors, with implications for broader clinical practice in donor eligibility evaluation, even in borderline renal cases. Furthermore, it confirms the feasibility of RST in living kidney donors and allows us to assess the sample size in 48 donors for a future study.

Robotic Versus Laparoscopic Donor Nephrectomy: A Retrospective Bicentric Comparison of Learning Curves and Surgical Outcomes From 2 High-volume European Centers.

BACKGROUND: Although laparoscopic donor nephrectomy (LDN) represents the gold-standard technique for kidney living donation, robotic donor nephrectomy (RDN) settled as another appealing minimally invasive technique over the past decades. A comparison between LDN and RDN outcomes was performed. METHODS: RDN and LDN outcomes were compared, focusing on operative time and perioperative risk factors affecting surgery duration. Learning curves for both techniques were compared through spline regression and cumulative sum models. RESULTS: The study analyzed 512 procedures (154 RDN and 358 LDN procedures) performed between 2010 and 2021 in 2 different high-volume transplant centers. The RDN group presented a higher prevalence of arterial variations (36.2 versus 22.4%; P = 0.001) compared with the LDN cohort. No open conversions occurred; operative time (210 versus 195 min; P = 0.011) and warm ischemia time (WIT; 230 versus 180 s; P < 0.001) were longer in RDN. Postoperative complication rate was similar (8.4% versus 11.5%; P = 0.49); the RDN group showed shorter hospital stay (4 versus 5 d; P < 0.001). Spline regression models depicted a faster learning curve in the RDN group ( P = 0.0002). Accordingly, cumulative sum analysis highlighted a turning point after about 50 procedures among the RDN cohort and after about 100 procedures among the LDN group.Higher body mass index resulted as an independent risk factor for longer operative time for both techniques; multiple arteries significantly prolonged operative time in LDN, whereas RDN was longer in right kidney procurements; both procedures were equally shortened by growing surgical experience. CONCLUSIONS: RDN grants a faster learning curve and improves multiple vessel handling. Incidence of postoperative complications was low for both techniques.

Legionella para-effectors target chromatin and promote bacterial replication.

Legionella pneumophila replicates intracellularly by secreting effectors via a type IV secretion system. One of these effectors is a eukaryotic methyltransferase (RomA) that methylates K14 of histone H3 (H3K14me3) to counteract host immune responses. However, it is not known how L. pneumophila infection catalyses H3K14 methylation as this residue is usually acetylated. Here we show that L. pneumophila secretes a eukaryotic-like histone deacetylase (LphD) that specifically targets H3K14ac and works in synergy with RomA. Both effectors target host chromatin and bind the HBO1 histone acetyltransferase complex that acetylates H3K14. Full activity of RomA is dependent on the presence of LphD as H3K14 methylation levels are significantly decreased in a ∆lphD mutant. The dependency of these two chromatin-modifying effectors on each other is further substantiated by mutational and virulence assays revealing that the presence of only one of these two effectors impairs intracellular replication, while a double knockout (∆lphD∆romA) can restore intracellular replication. Uniquely, we present evidence for "para-effectors", an effector pair, that actively and coordinately modify host histones to hijack the host response. The identification of epigenetic marks modulated by pathogens has the potential to lead to the development of innovative therapeutic strategies to counteract bacterial infection and strengthening host defences.

How Long Does It Take to Acquire Mastery of Performance in Laparoscopic Living Donor Nephrectomy? A Center-Based and Surgeon-Based Operative Time CUSUM Analysis.

BACKGROUND: The safety of laparoscopic donor nephrectomy (LDN) has been widely documented, but its challenging learning curve (LC) requires an insightful assessment to expand its application. The aim of this study was to evaluate LC of LDN in a high-volume transplant center. METHODS: Three hundred forty-three LDNs performed from 2001 to 2018 were evaluated. CUSUM analysis based on the operative time was used to assess the number of cases required to reach mastery in the technique for both the entire surgical team and for the 3 main surgeons considered separately. Analysis of association between demographics, perioperative characteristics, and complications within the different LC phases was conducted. RESULTS: Mean operative time was 228.9 minutes. Mean length of stay was 3.8 days and mean warm ischemia time (WIT) was 170.8 seconds. Surgical and medical complication rates were 7.3% and 6.4%, respectively. The CUSUM-LC showed a requirement of 157 cases (for surgical team) and 75 cases (for single surgeons) to reach competence in the procedure. Patient baseline characteristic showed no differences among the LC phases. Compared with the initial LC phase, hospital stay was significantly lower at the end of the LC whereas WIT results were longer in the LC descendent phase. CONCLUSIONS: This study confirms the safety and efficacy of LDN, with a low rate of complications. This analysis suggests that about 75 procedures are required to reach competence and 93 cases to achieve mastery level of skill for a single surgeon. It can be hypothesized that, in a high-volume transplant enter, the time to guarantee training in LDN is compatible with the duration of a clinical fellowship.

Bacterial methyltransferases: from targeting bacterial genomes to host epigenetics.

Methyltransferase (MTases) enzymes transfer methyl groups particularly on proteins and nucleotides, thereby participating in controlling the epigenetic information in both prokaryotes and eukaryotes. The concept of epigenetic regulation by DNA methylation has been extensively described for eukaryotes. However, recent studies have extended this concept to bacteria showing that DNA methylation can also exert epigenetic control on bacterial phenotypes. Indeed, the addition of epigenetic information to nucleotide sequences confers adaptive traits including virulence-related characteristics to bacterial cells. In eukaryotes, an additional layer of epigenetic regulation is obtained by post-translational modifications of histone proteins. Interestingly, in the last decades it was shown that bacterial MTases, besides playing an important role in epigenetic regulations at the microbe level by exerting an epigenetic control on their own gene expression, are also important players in host-microbe interactions. Indeed, secreted nucleomodulins, bacterial effectors that target the nucleus of infected cells, have been shown to directly modify the epigenetic landscape of the host. A subclass of nucleomodulins encodes MTase activities, targeting both host DNA and histone proteins, leading to important transcriptional changes in the host cell. In this review, we will focus on lysine and arginine MTases of bacteria and their hosts. The identification and characterization of these enzymes will help to fight bacterial pathogens as they may emerge as promising targets for the development of novel epigenetic inhibitors in both bacteria and the host cells they infect.

Outcome and quality of life of patients with augmented bladder or urinary diversion after kidney transplantation.

OBJECTIVE: The aim of the study was to assess results and quality of life after kidney transplant in adult patients with previously bladder augmentation or urinary diversion due to significant lower urinary tract dysfunction. MATERIALS AND METHODS: This cross-sectional study examines the outcome of 19 renal allografts transplanted in patients with augmented bladder or urinary diversion over a ten years period; moreover we submitted SF36 questionnaire to evaluate quality of life of these patients and compared the results with the general population. RESULT: Between January 1, 2005 and 31 December 2015 we performed 19/1093 renal transplantations in patients with abnormal lower urinary tract previously treated with bladder augmentation or bladder recycling. Current post-transplant follow-up was 47 months (range 18-188). No patient developed any episode of acute or chronic rejection. Mean serum creatinine after one year from transplant was 102 umol/L. Overall survival is 94.8% at the end of follow-up and graft survival is 89.6%. No significant differences emerged between patients undergoing transplant with lower urinary tract dysfunction and patients without, regarding to recurrent urinary tract infection. There was not statistically significant difference for vitality (p = 0.8088) and mental health (p = 0.8668). CONCLUSIONS: Presence of a previously augmented bladder or other lower urinary tract dysfunction treated in kidney transplant patients doesn't worsen the final outcome. Mental health and the vitality of these patients are similar to the general population.

Lower Urinary Tract Symptoms in Kidney Transplant Recipients and Timing of Treatment With TURP: Impact on Renal Graft Survival and Function.

BACKGROUND: With the aging of recipients of renal transplantation (RT) one of the emerging issues is the incidence of low urinary tract symptoms (LUTS), which may have negative consequences on the graft survival and function. The aim of our study was to assess the influence of LUTS and the treatment with transurethral resection of the prostate (TURP) on the outcome of RT. MATERIALS AND METHODS: We collected data from men over 55 who underwent RT at our center from January 2007 to December 2016. We analyzed the incidence of LUTS; the rate of treatment with TURP; the eGFR (estimated glomerular filtration rate) at 6 months and 1, 3, and 5 years from transplantation; and graft survival. RESULTS: Fifty-five patients out of 268 experienced LUTS, and 19 of them had a bladder outlet obstruction (BOO). Patients experiencing BOO had a significantly higher hazard ratio (HR) of graft failure (HR 5.7, CI 1.56-21.4) compared to the other recipients. Of the 18 patients treated with TURP, 10 received the procedure within 6 months from the LUTS onset. They had a significantly absolute eGFR improvement at 6 months from the intervention (+14.25 mL/min ± 8.10) compared to the patients treated later (-8.4 mL/min ± 14.43). DISCUSSION: We showed the negative effects of LUTS on kidney graft function and survival. Although TURP is the standard therapy for such an issue, the best timing for it still has to be defined. Our experience supports the need for an early treatment of the LUTS for promoting the outcome of the RT.

Deceased Donor-initiated Chains: First Report of a Successful Deliberate Case and Its Ethical Implications.

BACKGROUND: It has been suggested that deceased donor kidneys could be used to initiate chains of living donor kidney paired donation, but the potential gains of this practice need to be quantified and the ethical implications must be addressed before it can be implemented. METHODS: The gain of implementing deceased donor-initiated chains was measured with an algorithm, using retrospective data on the pool of incompatible donor/recipient pairs, at a single center. The allocation rules for chain-ending kidneys and the characteristics and quality of the chain-initiating kidney are described. RESULTS: The benefit quantification process showed that, with a pool of 69 kidneys from deceased donors and 16 pairs enrolled in the kidney paired donation program, it was possible to transplant 8 of 16 recipients (50%) over a period of 3 years. After obtaining the approval of the Veneto Regional Authority's Bioethical Committee and the revision of the Italian National Transplant Center's allocation policies, the first successful case was completed. For the recipient (male, aged 53 y), who entered the program for a chain-initiating kidney with a Kidney Donor Risk Index of 0.61 and a Kidney Donor Profile Index of 3%, the waiting time was 4 days. His willing donor (female, aged 53 y) with a Living Kidney Donor Profile Index of 2, donated 2 days later to a chain-ending recipient (male, aged 47 y) who had been on dialysis for 5 years. CONCLUSIONS: This is the first report of a successfully completed, deliberate deceased donor-initiated chain, which was made possible after a thorough assessment of the ethical issues and the impact of allocation policies. This article includes a preliminary efficacy assessment and describes the development of a dedicated algorithm.

Correction: Effects of immune suppression for transplantation on inflammatory colorectal cancer progression.

At the time of publication, the html version of this paper contained an error; the authors Imerio Angriman and Lucrezia Furian were not tagged as equally contributing authors. This has now been fixed in the html version of the paper, the PDF was correct at the time of publication.

Effects of immune suppression for transplantation on inflammatory colorectal cancer progression.

BACKGROUND: Ulcerative colitis patients and transplant recipients are at risk for colorectal cancer. Here, we show that immunosuppressive regimens for kidney transplants are associated with the progression of ulcerative colitis-related carcinogenesis. METHODS: We describe the case of a patient diagnosed with colorectal cancer in ulcerative colitis while on immunosuppressive therapy for a kidney transplant. The immunological microenvironment of the cancer and its mutational status were analyzed, and a mouse colon cancer model was created to replicate the unique clinical conditions. AOM/DSS mice were randomized into seven experimental groups that received different immunosuppressants and an untreated control group to assess the frequencies of adenocarcinoma and high-grade dysplasia. Histopathology, immunohistochemistry, and flow cytometry were also performed on the harvested mouse colons. RESULTS: All mice treated with an immunosuppressive regimen developed at least an adenoma, and several of those receiving anti-CD3, anti-CD8, and mycophenolate mofetil also developed adenocarcinomas. In contrast, mice receiving rapamycin did not develop adenocarcinomas, and the extent of high-grade dysplasia in those mice was similar to that in control mice. CONCLUSIONS: Patients with pre-neoplastic conditions, such as ulcerative colitis, who are undergoing a solid organ transplant might benefit from the use of mTOR inhibitors given their intrinsic anti-tumor properties.

Long-term outcome of renal transplantation from octogenarian donors: A multicenter controlled study.

To assess whether biopsy-guided selection of kidneys from very old brain-dead donors enables more successful transplantations, the authors of this multicenter, observational study compared graft survival between 37 recipients of 1 or 2 histologically evaluated kidneys from donors older than 80 years and 198 reference-recipients of non-histologically evaluated single grafts from donors aged 60 years and younger (transplantation period: 2006-2013 at 3 Italian centers). During a median (interquartile range) of 25 (13-42) months, 2 recipients (5.4%) and 10 reference-recipients (5.1%) required dialysis (crude and donor age- and sex-adjusted hazard ratio [95% confidence interval] 1.55 [0.34-7.12], P = .576 and 1.41 [0.10-19.54], P = .798, respectively). Shared frailty analyses confirmed similar outcomes in a 1:2 propensity score study comparing recipients with 74 reference-recipients matched by center, year, donor, and recipient sex and age. Serum creatinine was similar across groups during 84-month follow-up. Recipients had remarkably shorter waiting times than did reference-recipients and matched reference-recipients (7.5 [4.0-19.5] vs 36 [19-56] and 40 [24-56] months, respectively, P < .0001 for both comparisons). Mean (± SD) kidney donor risk index was 2.57 ± 0.32 in recipients vs 1.09 ± 0.24 and 1.14 ± 0.24 in reference-recipients and matched reference-recipients (P < .0001 for both comparisons). Adverse events were similar across groups. Biopsy-guided allocation of kidneys from octogenarian donors permits further expansion of the donor organ pool and faster access to a kidney transplant, without increasing the risk of premature graft failure.

Therapeutic apheresis in kidney AB0 incompatible transplantation.

Desensitization strategies to safely perform ABO incompatible living donor kidney transplantations are various and still evolving. Given the successful outcome of the majority of the approaches, the current trend is focused on a minimization of treatments. Based on this consideration, the evolution at a single Center of the desensitization protocol is herein described. Starting from 2010, 58 AB0 incompatible living donor kidney transplantations were performed at the University-Hospital of Padua. Over the years, the initial desensitization strategy with rituximab single-dose induction, pre-and post-transplant plasmapheresis and CMV-specific immunoglobulin administration has been shifted to a minimized approach, omitting post-transplant antibody removal in 25 cases. The results of such reduction in post-transplant antibody removal did not affect the outcome of AB0-incompatible kidney transplants, with a reduction in costs and hospitalization.

How does age affect the outcome of kidney transplantation in elderly recipients?

The aging of the on-dialysis population raises the issue of whether to propose elderly patients for kidney transplantation and how to manage their immunosuppression. This study aimed to analyze the outcome of kidney transplantation on an Italian series of elderly recipients. We included in this retrospective study all patients over 60 years, receiving a deceased-donor kidney transplantation from January 2004 to December 2014 in two north Italian Centers. We analyzed the correlation of recipient age with graft's and patient's survival, delayed graft function, acute cellular rejection (ACR), surgical complications, infections, and glomerular filtration rate. Four hundred and fifty-two patients with a median age of 65 years were included in the study. One-, 3-, and 5-year patient's and graft's survival were, respectively, of 98.7%, 93%, 89% and 94.4%, 87.9%, 81.4%. The increasing recipient age was an independent risk factor only for the patient's (P=.008) and graft's survival (P=.002). ACR and neoplasia were also associated to a worse graft survival. The reduced graft survival in elderly kidney recipients seems to be related more to the increasing recipient's age than to the donor's features. In this population, the optimization of organ allocation and immunosuppression may be the key factors to endorse improvements.

A single-center experience with 200 dual kidney transplantations.

This study reports on a large series of 200 dual kidney transplantations (DKTs) from expanded criteria donors (ECDs) and proposes specific ways to optimize outcomes. Data concerning 200 DKTs performed in the last 14 yr were retrospectively analyzed. Kidneys from high-risk ECD were allocated for use in DKTs on an old-for-old basis after histological assessment. Different surgical techniques and immunosuppressant regimens were used over time, and the outcomes are discussed. Donors and recipients were a median 73 (70-77) and a 62 (58-67) yr old, respectively. Delayed graft function occurred in 31.5% of cases, and acute rejection in 13.5%. Patient and graft survival at five yr were 90.4% and 85.8%, respectively. Unilateral kidney placement was preferred for 75% of patients, and was associated with a low rate of surgical complications. Our current standard therapy comprising low-dose calcineurin inhibitors (CNIs) associated with mammalian target of rapamycin inhibitors (mTOR) and steroids appears to offer the best risk/benefit profile for elderly patients undergoing DKT. In our experience, outcomes after DKT can be improved by: (i) kidney clinical-histological assessment; (ii) unilateral kidney placement; (iii) minimal use of CNI associated with mTOR.

Comparison of cytomegalovirus (CMV) enzyme-linked immunosorbent spot and CMV quantiferon gamma interferon-releasing assays in assessing risk of CMV infection in kidney transplant recipients.

Assessing cytomegalovirus (CMV)-specific cell-mediated immunity (CMI) represents an appealing strategy for identifying transplant recipients at risk of infection. In this study, we compared two gamma interferon-releasing assays (IGRAs), Quantiferon-CMV and CMV enzyme-linked immunosorbent spot (ELISPOT), to determine the ability of each test to predict protective CMV-specific T-cell responses. Two hundred twenty-one Quantiferon-CMV and ELISPOT tests were conducted on 120 adult kidney transplant recipients (KTRs), including 100 CMV-seropositive transplant recipients (R+) and 20 CMV-seronegative transplant recipients of a CMV-positive donor (D+/R-). As a control cohort, 39 healthy adult subjects (including 33 CMV-seropositive and 6 CMV-seronegative subjects) were enrolled. CMV IgG serology was used as a reference for both tests. In the CMV-seropositive individuals, the ELISPOT and Quantiferon-CMV assays provided 46% concordance with the serology, 12% discordance, 18% disagreement between ELISPOT or Quantiferon-CMV and the serology, and 24% gray areas when one or both tests resulted in weak positives. None of the CMV-seronegative subjects showed detectable responses in the ELISPOT or the Quantiferon-CMV test. In transplant recipients, both the ELISPOT and Quantiferon-CMV assays positively correlated with each other and negatively correlated with CMV DNAemia in a significant way (P<0.05). During the antiviral prophylaxis, all 20 D+/R- KTRs we examined displayed undetectable Quantiferon-CMV and ELISPOT results, and there was no evidence of CMV seroconversion. The receiving operator curve (ROC) statistical analysis revealed similar specificities and sensitivities in predicting detectable viremia (areas under the curve [AUC], 0.66 and 0.62 for Quantiferon-CMV and ELISPOT, respectively). ELISPOT and Quantiferon-CMV values of >150 spots/200,000 peripheral blood mononuclear cells (PBMCs) and >1 to 6 IU gamma interferon (IFN-γ) were associated with protection from CMV infection (odds ratios [OR], 5 and 8.75, respectively). In transplant recipients, the two tests displayed similar abilities for predicting CMV infection. Both the ELISPOT and Quantiferon-CMV assays require several ameliorations to avoid false-negative results.

Cadmium telluride nanocrystals as luminescent sensitizers in flow analysis.

A fully automated multipumping flow system (MPFS) using water-soluble CdTe quantum dots (QD) as sensitizers is proposed for the chemiluminometric determination of the anti-diabetic drugs gliclazide and glipizide in pharmaceutical formulations. The nanocrystals acted as enhancers of the weak CL emission produced upon oxidation of sulphite by Ce(IV) in acidic medium, thus improving sensitivity and expanding the dynamical analytical concentration range. By interacting with the QD, the two analytes prevented their sensitizing effect yielding a chemiluminescence quenching of the Ce(IV)-SO(3)(2-)CdTe QD system. The pulsed flow inherent to MPFS assured a fast and efficient mixing of all solutions inside the flow cell, circumventing the need for a reaction coil and facilitating the monitoring of the short-lived generated chemiluminescent species. QD crystal size, concentration and spectral region for measurement were investigated.

Quantum dots assisted photocatalysis for the chemiluminometric determination of chemical oxygen demand using a single interface flow system.

A novel flow method for the determination of chemical oxygen demand (COD) is proposed in this work. It relies on the combination of a fully automated single interface flow system, an on-line UV photocatalytic unit and quantum dot (QD) nanotechnology. The developed approach takes advantage of CdTe nanocrystals capacity to generate strong oxidizing species upon irradiation with UV light, which fostered a fast catalytic degradation of the organic compounds. Luminol was used as a chemiluminescence (CL) probe for indirect COD assessment, since it is easily oxidized by the QD generated species yielding a strong CL emission that is quenched in the presence of the organic matter. The proposed methodology allowed the determination of COD concentrations between 1 and 35 mg L(-1), with good precision (R.S.D.<1.1%, n=3) and a sampling frequency of about 33 h(-1). The procedure was applied to the determination of COD in wastewater certified reference materials and the obtained results showed an excellent agreement with the certified values.