Avascular Necrosis in Kidney Transplant Recipients is Associated With an Increased Risk of Patient Death

Introduction: Avascular necrosis is a debilitating osseous complication in transplant recipients. Project Aim: This program evaluation sought to describe risk factors and adverse outcomes of avascular necrosis in kidney transplant recipients. Design: This was a retrospective evaluation of all recipients of kidneys and simultaneous pancreas and kidneys between 2001 and 2018 from a single center. Controls were selected based on the incidence density, sampling at a 1:3 ratio based on the post-transplant interval. Outcomes of interest were acute rejection, death-censored graft failure, and patient mortality. Results: A total of 88 kidney recipients had avascular necrosis and were compared with 257 controls. Most of the recipient's and donors' baseline characteristics were similar between the groups, except calcineurin inhibitor-based immunosuppression was more prevalent, and non-white donors were less prevalent in the control group. Looking for risk factors for avascular necrosis, calcineurin inhibitor-based immunosuppression was associated with a lower risk for avascular necrosis in the univariate analysis, but this was not found after adjustment of multiple variables. In multivariate analysis, avascular necrosis was associated with an increased risk for patient death (hazard ratio: 1.68; 95% confidence interval: 1.16-2.44; P = .008) but not for acute rejection or death censored graft failure. Conclusion: Although limited by small sample size, this evaluation found avascular necrosis to be associated with an increased risk of patient death. This finding may be useful for the provider taking care of the patients and discussing the various outcomes after the transplant.

Effect of End-Stage Renal Disease Prospective Payment System on Utilization of Peritoneal Dialysis in Patients with Kidney Allograft Failure

INTRODUCTION

The Center for Medicare and Medicaid Services (CMS) introduced an End Stage Renal Disease (ESRD) Prospective Payment System (PPS) in 2011 to increase the utilization of home dialysis modalities, including peritoneal dialysis (PD). Several studies have shown a significant increase in PD utilization after PPS implementation. However, its impact on patients with kidney allograft failure remains unknown.

METHODS

We conducted an interrupted time series (ITS) analysis using data from the United States Renal Data System (USRDS) that include all adult kidney transplant recipients with allograft failure who started dialysis between 2005 and 2019. We compared the PD utilization in the pre-PPS period (2005-2010) to the fully implemented post-PPS period (2014 - 2019) for early (within 90 days) and late (91-365 days) PD experience.

RESULTS

27507 adult recipients with allograft failure started dialysis during the study period. There was no difference in early PD utilization between the pre-PPS and the post-PPS period in either immediate change (0.3% increase; 95%CI: -1.95%, 2.54%; p=0.79) or rate of change over time (0.28% increase per year; 95%CI: -0.16%, 0.72%; p=0.18). Subgroup analyses revealed a trend toward higher PD utilization post-PPS in for-profit and large-volume dialysis units. There was a significant increase in PD utilization in the post-PPS period in units with low PD experience in the pre-PPS period. Similar findings were seen for the late PD experience.

CONCLUSION

PPS did not significantly increase the overall utilization of PD in patients initiating dialysis after allograft failure.

Twelve Thousand Kidney Transplants Over More Than 55 Y: A Single-center Experience

Background

Kidney transplant outcomes have dramatically improved since the first successful transplant in 1954. In its early years, kidney transplantation was viewed more skeptically. Today it is considered the treatment of choice among patients with end-stage kidney disease.

Methods

Our program performed its first kidney transplant in 1966 and recently performed our 12 000th kidney transplant. Here, we review and describe our experience with these 12 000 transplants. Transplant recipients were analyzed by decade of date of transplant: 1966-1975, 1976-1985, 1986-1995, 1996-2005, 2006-2015, and 2016-2022. Death-censored graft failure and mortality were outcomes of interest.

Results

Of 12 000 kidneys, 247 were transplanted from 1966 to 1975, 1147 from 1976 to 1985, 2194 from 1986 to 1995, 3147 from 1996 to 2005, 3046 from 2006 to 2015, and 2219 from 2016 to 2022 compared with 1966-1975, there were statistically significant and progressively lower risks of death-censored graft failure at 1 y, 5 y, and at last follow-up in all subsequent eras. Although mortality at 1 y was lower in all subsequent eras after 1986-1995, there was no difference in mortality at 5 y or the last follow-up between eras.

Conclusions

In this large cohort of 12 000 kidneys from a single center, we observed significant improvement in outcomes over time. Kidney transplantation remains a robust and ever-growing and improving field.

Risk factors and outcomes of persistent post-transplant hypotension among simultaneous pancreas and kidney transplant recipients

BACKGROUND

The risk factors and outcomes associated with post- transplant hypotension after simultaneous pancreas and kidney (SPK) Transplantation are poorly defined.

METHODS

SPK recipients at our center between 2010 and 2021 with functioning pancreas and kidney grafts for >6 months were included. Recipients were then divided into three groups based on active medications for the treatment of hypo-or hypertension at 6-months post-transplant: those with normal blood pressure (NBP) not requiring medication (NBP group), those on antihypertensive medications (HTN group), and those on medications for hypotension (fludrocortisone and/or midodrine) (Hypotensive group).

RESULTS

A total of 306 recipients were included in the study: 54 (18%) in the NBP group, 215 (70%) in the HTN group, and 37 (12%) in the Hypotensive group. On multivariate analysis, the use of T-depleting induction (aHR = 9.64, p = .0001, 95% Cl = 3.12-29.75), pre-transplant use of hypotensive medications (aHR = 4.53, p = .0003, 95% Cl = 1.98-10.38), and longer duration of dialysis (aHR = 1.02, p = .01, 95% Cl = 1.00-1.04) were associated with an increased risk of post-transplant hypotension. Post-transplant hypotension was not associated with an increased risk of death-censored kidney or pancreatic allograft failure, or patient death.

CONCLUSION

Hypotension was common even 6 months post-SPK transplantation. With appropriate management, hypotension was not associated with detrimental graft or patient outcomes.

Hypoalbuminemia is a risk factor for invasive fungal infections and poor outcomes in infected kidney transplant recipients

INTRODUCTION

Invasive fungal infections (IFI), are estimated to occur in 2%-14% of kidney transplant recipients (KTRs) in the current era of immune suppression and are associated with high mortality rates. We hypothesized that hypoalbuminemia in KTRs is a risk factor for IFI and would be associated with poor outcomes.

METHODS

In this study, using data from a prospective cohort registry, we describe the frequency of IFI due to Blastomycosis, Coccidioidomycosis, Histoplasmosis, Aspergillosis, and Cryptococcus in KTRs with serum albumin levels measured 3-6 months before diagnosis. Controls were selected based on incidence density sampling. KTRs were divided into three groups based on the pre-IFI serum albumin level: normal (≥4 g/dL), mild (3-4 g/dL), or severe (<3 g/dL) hypoalbuminemia. Outcomes of interest were uncensored graft failure after IFI and overall mortality.

RESULTS

A total of 113 KTRs with IFI were compared with 348 controls. The incidence rate of IFI among individuals with normal, mild, and severe hypoalbuminemia was 3.6, 8.7, and 29.3 per 100 person-years, respectively. After adjustment for multiple variables, the trend for risk of uncensored graft failure following IFI was greater in KTRS with mild (HR = 2.1; 95% CI, .75-6.1) and severe (HR = 4.47; 95% CI, 1.56-12.8) hypoalbuminemia (P-trend < .001) compared to those with normal serum albumin. Similarly, mortality was higher in severe hypoalbuminemia (HR = 1.9; 95% CI, .67-5.6) compared to normal serum albumin (P-trend < .001).

CONCLUSION

Hypoalbuminemia precedes the diagnosis of IFI in KTRs, and is associated with poor outcomes following IFI. Hypoalbuminemia may be a useful predictor of IFI in KTRs and could be incorporated into screening algorithms.

Delayed Graft Function Among Kidney Transplant Recipients Is Associated With an Increased Risk of Urinary Tract Infection and BK Viremia

Background

Delayed graft function (DGF) among deceased donor kidney transplant recipients (DDKTRs) is a well-known risk factor for allograft rejection, decreased graft survival, and increased cost. Although DGF is associated with an increased risk of rejection, it is unclear whether it also increases the risk of infection.

Methods

We reviewed all adult DDKTRs at our center between 2010 and 2018. The primary outcomes of interest were BK viremia, cytomegalovirus viremia, pneumonia, and urinary tract infection (UTI) within the first year of transplant. Additional analysis was made with censoring follow-up at the time of allograft rejection.

Results

A total of 1512 DDKTRs were included, of whom 468 (31%) had DGF. As expected, several recipient, donor, and baseline immunological characteristics differed by DGF status. After adjustment, DGF was significantly associated with an increased risk of BK viremia (hazard ratio: 1.34; 95% confidence interval, 1.0-1.81; P = 0.049) and UTI (hazard ratio: 1.70; 95% confidence interval, 1.31-2.19; P < 0.001) but not cytomegalovirus viremia or pneumonia. Associations were similar in models censored at the time of rejection.

Conclusions

DGF is associated with an increased risk of early infectious complications, mainly UTI and BK viremia. Close monitoring and appropriate management are warranted for better outcomes in this unique population.

Analysis of Individual Components of Frailty in Simultaneous Pancreas and Kidney, and Solitary Pancreas Transplant Recipients

Backgrounds

It is not known which of the 5 components of the Fried frailty score have the most predictive value for outcomes in simultaneous pancreas-kidney transplant (SPK) and solitary pancreas transplant (SPT) recipients.

Methods

In this study, we sought to investigate the association between pretransplant overall frailty and individual frailty components, with posttransplant outcomes among SPK and SPT recipients. Outcomes of interest were length of stay, kidney delayed graft function (K-DGF), readmission within 30 d after discharge, cardiovascular events, acute rejection, pancreas death-censored graft failure (DCGF), kidney DCGF, and death.

Results

Of the individual frailty components among SPK (n = 113), only slow walk time was associated with an increased risk of mortality (adjusted odds ratio [aOR]: 4.99; P = 0.03). Among SPT (n = 49), higher sum frailty scores (coefficient correlation 0.29; P = 0.04) and weight loss (coefficient correlation  = 0.30; P = 0.03) were associated with prolonged length of stay. Similarly, weight loss among SPT was associated with an increased risk of DCGF (aOR: 4.34; P = 0.049). Low grip strength was strongly associated with an increased risk of early readmission (aOR: 13.08; P = 0.008).

Conclusions

We found that not all components of frailty contribute equally to predicting outcomes. Objective measurements of slow walk time, unintentional weight loss, and low grip strength were found to be associated with less optimal outcomes in pancreas transplant recipients. Targeted interventions may improve posttransplant outcomes.

Pseudohyponatremia: Mechanism, Diagnosis, Clinical Associations and Management

Pseudohyponatremia remains a problem for clinical laboratories. In this study, we analyzed the mechanisms, diagnosis, clinical consequences, and conditions associated with pseudohyponatremia, and future developments for its elimination. The two methods involved assess the serum sodium concentration ([Na]_S) using sodium ion-specific electrodes: (a) a direct ion-specific electrode (ISE), and (b) an indirect ISE. A direct ISE does not require dilution of a sample prior to its measurement, whereas an indirect ISE needs pre-measurement sample dilution. [Na]_S measurements using an indirect ISE are influenced by abnormal concentrations of serum proteins or lipids. Pseudohyponatremia occurs when the [Na]_S is measured with an indirect ISE and the serum solid content concentrations are elevated, resulting in reciprocal depressions in serum water and [Na]_S values. Pseudonormonatremia or pseudohypernatremia are encountered in hypoproteinemic patients who have a decreased plasma solids content. Three mechanisms are responsible for pseudohyponatremia: (a) a reduction in the [Na]_S due to lower serum water and sodium concentrations, the electrolyte exclusion effect; (b) an increase in the measured sample's water concentration post-dilution to a greater extent when compared to normal serum, lowering the [Na] in this sample; (c) when serum hyperviscosity reduces serum delivery to the device that apportions serum and diluent. Patients with pseudohyponatremia and a normal [Na]_S do not develop water movement across cell membranes and clinical manifestations of hypotonic hyponatremia. Pseudohyponatremia does not require treatment to address the [Na]_S, making any inadvertent correction treatment potentially detrimental.

Ixazomib for Desensitization (IXADES) in Highly Sensitized Kidney Transplant Candidates: A Phase II Clinical Trial

Key Points

Ixazomib treatment resulted in decreases in B-cell subsets and bone marrow lymphocytes. Ixazomib treatment resulted in modest decreases in certain anti-HLA antibody specificities. Ixazomib treatment was tolerated, with modest adverse events.

Background

Ixazomib is a second-generation oral proteasome inhibitor approved for treatment of refractory multiple myeloma. We conducted an open-label phase II trial, IXAzomib for DESensitization (IXADES), testing the safety of ixazomib treatment as an approach to decreasing the level and diversity of specificities of anti-HLA antibodies in subjects awaiting kidney transplantation. The trial (NCT03213158 ) enrolled highly sensitized kidney transplant candidates, defined as subjects with calculated panel reactive antibodies (cPRA) >80%, awaiting kidney transplantation >24 months. The subjects were treated with 12 monthly cycles of ixazomib 3 mg+dexamethasone 20 mg. Efficacy was defined as a decrease of cPRA >20% or kidney transplantation. The safety end point was tolerability.

Methods

In ten enrolled subjects, no grade IV, five grade III, 11 grade II, and 43 grade I adverse events were noted. The adverse events included infection, transient paresthesia, nausea, vomiting, and diarrhea. The IXADES regimen was not associated with significant change in levels or diversity of anti-HLA antibodies (cPRA).

Results

Although the IXADES regimen did not exhibit a clear impact on levels and diversity of anti-HLA antibodies in this small cohort, the prolonged half-life of IgG could necessitate a longer duration of treatment for accurate evaluation of efficacy.

Conclusions

In conclusion, treatment with ixazomib/dexamethasone engendered mild-to-moderate toxicity. The impact on anti-HLA was modest and paradoxical in the case of anti-HLA-DR. Clinical trials combining ixazomib with other immunosuppressive agents may be more effective in addressing antibody-mediated processes in kidney transplantation.

The Trend of Serum Creatinine Does Not Predict Follow-Up Biopsy Findings Among Kidney Transplant Recipients With Antibody-Mediated Rejection

Traditionally, antibody-mediated rejection (AMR) has been suspected mainly by a rise in serum creatinine (Scr) and confirmed by allograft biopsy. There is limited literature describing the trend of Scr after treatment, and how that trend might differ between patients with histological response and with no response to treatment.

Methods

We included all cases of AMR at our program between March 2016 and July 2020 who had a follow-up biopsy after the index biopsy, with initial diagnosis of AMR. We trended the Scr and change in Scr (delta Scr) and its association with being a responder (microvascular inflammation, MVI ≤1) or nonresponder (MVI >1), as well as graft failure.

Results

A total of 183 kidney transplant recipients were included, 66 in the responder group and 177 in the nonresponder group. The MVI scores and sum chronicity scores, along with transplant glomerulopathy scores, were higher in the nonresponder group. However, Scr at index biopsy was similar in responders (1.74 ± 0.70) versus nonresponders (1.83 ± 0.65; P = 0.39), as were the delta Scr at various time points. After adjustment for multiple variables, delta Scr was not associated with being a nonresponder. Also, delta Scr value at follow-up biopsy compared with index biopsy among responders was 0 ± 0.67 (P = 0.99) and among nonresponders was -0.01 ± 0.61 (P = 0.89). Being a nonresponder was significantly associated with an increased risk of graft failure at the last follow-up in univariate analysis but was not in multivariate analysis (hazard ratio 1.35; 95% confidence interval, 0.58-3.17; P = 0.49).

Conclusions

We found that Scr is not a good predictor of the resolution of MVI, supporting the utility of follow-up biopsies after treatment of AMR.

Pre-transplant hypoalbuminemia is not associated with worse short-term outcomes among kidney transplant recipients

INTRODUCTION

Serum albumin is an indicator of overall health status, but it remains unclear how pre-transplant hypoalbuminemia is associated with early post-transplant outcomes.

METHODS

This study included all adult kidney transplant recipients (KTRs) at our center from 01/01/2001-12/31/2017 with serum albumin measured within 30 days before transplantation. KTRs were grouped based on pretransplant albumin level normal (≥4.0 g/dL), mild (≥3.5 - < 4.0g/dL), moderate (≥3.0 - < 3.5g/dL), or severe hypoalbuminemia (<3.0g/dL). Outcomes of interest included: length of hospital stay (LOS), readmission within 30 days, delayed graft function(DGF), and re-operation related to post-transplant surgical complications. We also analyzed rejection, graft failure, and death within 6 months post-transplant.

RESULTS

A total of 2807 KTRs were included 43.6% had normal serum albumin, 35.3% mild, 16.6% moderate, and 4.5% severe hypoalbuminemia. Mild and moderate hypoalbuminemia were associated with a shorter LOS by 1.22 (p < 0.001) and 0.80 days (p = 0.01), respectively, compared to normal albumin. Moderate (HR: 0.58; 95% CI: 0.37-0.91; p = 0.02) and severe hypoalbuminemia (HR: 0.21; 95% CI: 0.07-0.68; p = 0.01) were associated with significantly lower rates of acute rejection within 6 months post-transplant.

CONCLUSION

Patients with pre-transplant hypoalbuminemia have post-transplant outcomes similar to those with normal serum albumin, but with a lower risk of acute rejection based on the degree of hypoalbuminemia.

Secondary oxalate nephropathy and kidney transplantation

PURPOSE OF REVIEW

Secondary hyperoxaluria is associated with poor kidney allograft outcomes after the kidney transplant. Calcium oxalate (CaOx) deposition is common in early allograft biopsies leading to acute tubular necrosis and poor kidney allograft function. Though treatment options for secondary hyperoxaluria are limited, it is crucial to identify patients at increased risk of oxalate nephropathy after the transplant.

RECENT FINDINGS

Recent data suggest that significant changes in renal replacement therapies and dietary modifications in high-risk patients can prevent kidney allograft damage from the calcium oxalate deposition leading to improve allograft outcomes.

SUMMARY

The accurate and timely diagnosis of secondary oxalate nephropathy in kidney transplant recipients is paramount to preserving graft function in the long-term. This review will discuss the incidence, risk factors, prevention, and management of oxalate nephropathy in the kidney allograft.

Electrochemical quantification of atrazine-fulvic acid and removal through bismuth tungstate photocatalytic hybrid membranes

Herbicides such as atrazine and humus substances such as fulvic acid are widely used in agricultural sector. They can be traced in surface and groundwater around the agriculture field at concentrations beyond the approved limit due to their mobility and persistence. Bismuth-based photocatalysts activated by visible light are potential materials for removing various organic pollutants from water bodies. These photocatalysts can also be suitable candidates for developing a hybrid membrane with anti-fouling properties. In this study, Bi2WO6 nanoparticles were synthesized via the hydrothermal method and integrated into the cellulose acetate (CA), polyetherimide (PEI), polysulfone (PSF) and polyvinylidene fluoride (PVDF) polymers via physical blending approach. The hybrid membranes were then characterized by FTIR, XPS and FESEM to confirm the chemical bonding, chemical composition and surface morphology of Bi2WO6. Thus, the pure water flux of CA (35.6 L m-2 h-1), PEI (46.56 L m-2 h-1), PSF (6.84 L m-2 h-1), and PVDF (68.47 L m-2 h-1) hybrid membranes has significantly enhanced than the pristine CA, PEI, PSF and PVDF membranes. The significant rejection of atrazine-fulvic acid was observed with hybrid membranes in the order of CA (84.1%) > PVDF (72.7%) > PEI (47.8%) > PSF (37.2%), and these membranes have shown an excellent flux recovery ratio than pristine membranes. Further, electrochemical quantification studies were performed to analyze the removal efficiency of atrazine-fulvic acid from water. In this present work, GO-modified SPE was employed for electrochemical sensing studies. The resultant CA hybrid membrane achieved removal efficiency of 84.08% for atrazine. It was observed that the Bi2WO6 established strong bonding with CA, and PVDF membranes, thus showing a significant removal efficiency and FRR than other hybrid and pristine membranes.

Seasonal variation of cytomegalovirus disease in kidney transplant recipients

PURPOSE

Studies conducted in the northern United States found cytomegalovirus (CMV) disease after liver transplantation follows a seasonal pattern, with increased incidence in fall and winter. This has not been evaluated in kidney transplant recipients. Improved understanding of CMV seasonality may help guide use of preventative therapies.

METHODS

We evaluated adult patients receiving a kidney transplant at our center in Wisconsin from January 1, 1995 to December 31, 2018. CMV event was defined as quantifiable viral replication with clinical signs or symptoms suspicious for CMV per current consensus recommendations. Seasons were divided as follows: winter (December-February), spring (March-May), summer (June-August), and fall (September-November). The primary objective was to evaluate the annual distribution of CMV disease and determine whether this differed by season.

RESULTS

There were 6151 kidney transplants in the study period. A total of 913 patients had 1492 episodes of CMV. Median time from transplant to first detection was 5.51 months (interquartile range [IQR] 2.87-11.7). The observed overall incidence exceeded the expected incidence in winter (+.7%), spring (+5.5%), and fall (+3.4%) and was less than expected in summer (-9.5%) (p = .18). The incidence of CMV during summer, however, was 21% less than expected (p = .001) in recipients who were CMV positive (R+) at the time of transplantation. No such difference was observed in CMV negative recipients (R-; p = .58).

CONCLUSION

CMV after kidney transplant appears to be less common during the summer season in patients who were R+ at transplant but does not follow seasonal variation in R-. Reasons for this are unclear but are likely related to CMV-specific cell-mediated immunity. These findings may have clinical implications, particularly the use of non-pharmacologic strategies to improve response to antiviral therapy.

Analysis of individual components of frailty: Pre-transplant grip strength is the strongest predictor of post kidney transplant outcomes

Frailty is commonly assessed during kidney transplant recipient (KTR) evaluation. However, individual frailty components may have varying impact on post-transplant outcomes. In this single-center study of 825 KTRs, we determined the association between the individual components of a modified Fried frailty score and delayed graft function (DGF), early hospital readmission (EHR), cardiovascular (CV) events, acute rejection (AR), death censored graft failure (DCGF), and death. Sum frailty ≥3 was significantly associated with EHR (aOR = 3.62; 95% CI: 1.21-10.80). Among individual components, only grip strength was significantly associated with EHR (aOR = 1.54; 95% CI: 1.03-2.31). The addition of grip strength to a model with the other four components resulted in Net Reclassification Improvement (NRI) of 20.51% (p = .01). Similarly, only grip strength was significantly associated with CV events (aOR = 1.79; 95% CI: 1.12-2.86). The addition of grip strength to a model with the other four components resulted in NRI of 27.37% (p = .006). No other frailty components were associated with the outcomes of interest. Based on our findings, handgrip strength may be an important tool while assessing frailty, mainly predicting early readmission and cardiovascular events post-transplant.

Comparison of ELISA and PCR Assays for Detection of Pork Adulteration in Halal-Labelled Beef Products

Background: Food adulteration with pork in processed beef products is one of the most serious issues in a food sector in a Muslim-majority country since it is related to religious food ethics regarding the halal products. The goal of this research is to test the suitability of ingredients in beef floss and its Halal by knowing the presence of porkDNA and  protein in those products. Methods: Meat products were prepared from two famous marketplaces in Indonesia labeled contain beef meat. In this study, a qualitative Enzyme-Linked Immunosorbent Assay (ELISA) test was compared to a conventional Polymerase Chain Reaction (PCR) assay to determine pork adulteration in beef floss. Results: The results of the ELISA test showed that two products labeling Halal and containing beef ingredients were positive for pork. Those two samples continued testing using conventional PCR assay. The result of the conventional PCR assay was negative for those two samples. Conclusion: It may be helpful to utilize both traditional PCR and ELISA for species detection due to the possibly inhibiting compounds contained in some processed meat products. The results of this research suggest that ELISA is better than conventional PCR method for product samples that have received an intensive heating process.

In kidney recipients from the same deceased donor, discordance in delayed graft function is associated with the worst outcomes

Delayed graft function(DGF) is a common complication among deceased donor kidney transplant recipients(DDKTs) and is associated with worse outcomes. The effect on outcomes of concordance versus discordance in DGF between two different recipients of kidneys from the same donor is largely unknown. We reviewed all adult DDKTs for which both kidneys were transplanted to two different recipients at our center between 2014-2019. DDKTs were divided into four groups based on the DGF status: concordance no DGF(cc-no-DGF); discordance no DGF(dd-no-DGF); discordance DGF(dd-DGF) and concordance in DGF(cc-DGF). Acute rejection (AR) and death censored graft failure (DCGF) were outcomes of interest. A total of 578 DDKTs fulfilled our selection criteria, 280 were in cc-no-DGF, 83 in dd-no-DGF, 83 in dd-DGF, and 132 in cc-DGF. Compared to cc-no-DGF, in univariate analysis, dd-DGF was associated with an increased risk of AR(HR:1.60; 95% CI:1.0-2.56) but cc-DGF was not(HR:1.01; 95% CI:0.63-1.62). dd-DGF was not associated with an increased risk of AR in multivariate analysis. In multivariate analysis, dd-DGF was associated with an increased risk of DCGF (HR: 2.70; 95% CI: 1.05-6.93) but cc-DGF was not (HR:2.36; 95% CI:0.97-5.70). Discordance in DGF is associated with worse outcomes and may need close follow-up and monitoring to improve the outcomes. This article is protected by copyright. All rights reserved.

Comparative molecular dynamics simulations of thermal conductivities of aqueous and hydrocarbon nanofluids

The addition of metal oxide nanoparticles to fluids has been used as a means of enhancing the thermal conductive properties of base fluids. This method formulates a heterogeneous fluid conferred by nanoparticles and can be used for high-end fluid heat-transfer applications, such as phase-change materials and fluids for internal combustion engines. These nanoparticles can enhance the properties of both polar and nonpolar fluids. In the current paper, dispersions of nanoparticles were carried out in hydrocarbon and aqueous-based fluids using molecular dynamic simulations (MDS). The MDS results have been validated using the autocorrelation function and previous experimental data. Highly concurrent trends were achieved for the obtained results. According to the obtained results of MDS, adding CuO nanoparticles increased the thermal conductivity of water by 25% (from 0.6 to 0.75 W·m^-1·K^-1). However, by adding these nanoparticles to hydrocarbon-based fluids (i.e., alkane) the thermal conductivity was increased three times (from 0.1 to 0.4 W·m^-1·K^-1). This approach to determine the thermal conductivity of metal oxide nanoparticles in aqueous and nonaqueous fluids using visual molecular dynamics and interactive autocorrelations demonstrate a great tool to quantify thermophysical properties of nanofluids using a simulation environment. Moreover, this comparison introduces data on aqueous and nonaqueous suspensions in one study.

New Approaches to Cardiovascular Disease and Its Management in Kidney Transplant Recipients

Cardiovascular events, including ischemic heart disease, heart failure, and arrhythmia, are common complications after kidney transplantation and continue to be leading causes of graft loss. Kidney transplant recipients have both traditional and transplant-specific risk factors for cardiovascular disease. In the general population, modification of cardiovascular risk factors is the best strategy to reduce cardiovascular events; however, studies evaluating the impact of risk modification strategies on cardiovascular outcomes among kidney transplant recipients are limited. Furthermore, there is only minimal guidance on appropriate cardiovascular screening and monitoring in this unique patient population. This review focuses on the limited scientific evidence that addresses cardiovascular events in kidney transplant recipients. Additionally, we focus on clinical management of specific cardiovascular entities that are more prevalent among kidney transplant recipients (ie, pulmonary hypertension, valvular diseases, diastolic dysfunction) and the use of newer evolving drug classes for treatment of heart failure within this cohort of patients. We note that there are no consensus documents describing optimal diagnostic, monitoring, or management strategies to reduce cardiovascular events after kidney transplantation; however, we outline quality initiatives and research recommendations for the assessment and management of cardiovascular-specific risk factors that could improve outcomes.

The Presence of Donor-specific Antibodies Around the Time of Pancreas Graft Biopsy With Rejection Is Associated With an Increased Risk of Graft Failure

BACKGROUND

Donor-specific antibodies (DSA) against HLA are an important biomarker predicting graft injury, rejection (Rej), and failure in various solid-organ transplant recipients. However, the impact of DSA with or without histopathological evidence of rejection among pancreas transplant recipients (PTRs) is unknown.

METHODS

In this study, we included all PTRs at our center between 2005 and 2020, with pancreas allograft biopsy before March 31, 2021, and with DSA checked within 15 d of the biopsy. PTRs were divided into 4 groups based on the biopsy findings on the index biopsy and DSA status as Rej-/DSA-, Rej+/DSA-, Rej-/DSA+, and Rej+/DSA+.

RESULTS

Two hundred two PTRs had a pancreas allograft biopsy during the study period. Thirty-nine were in Rej-/DSA-, 84 Rej+/DSA-, 24 Rej-/DSA+, and 55 Rej+/DSA+. The mean interval from transplant to index biopsy was not statistically different between the 4 groups. The most common type of rejection was T cell-mediated rejection; however, antibody-mediated rejection was more prevalent in the Rej+/DSA+ group. At 5 y postbiopsy, the rate of death-censored graft failure (DCGF) for Rej-/DSA- was 18%, 24% in Rej+/DSA-; 17% in Rej-/DSA+ and 36% in Rej+/DSA+ (P = 0.14). In univariate analysis, mixed rejection (hazard ratio [HR], 3.0; 95% confidence intervals [CI], 1.22-7.39; P = 0.02) along with solitary pancreas transplantation and Rej+/DSA+ were associated with DCGF. In multivariate analysis, compared with Rej-/DSA-, Rej+/DSA+ was significantly associated with DCGF (HR, 2.32; 95% CI, 1.03-5.20; P = 0.04); however, Rej+/DSA- was not (HR, 1.06; 95% CI, 0.32-3.56; P = 0.92).

CONCLUSIONS

PTRs with pancreas allograft rejection and concomitant DSA have an increased risk of DCGF.

The Role of Peritoneal Dialysis in Different Phases of Kidney Transplantation

The utilization of peritoneal dialysis (PD) has been increasing in the past decade owing to various government initiatives and recognition of benefits such as better preservation of residual renal function, quality of life, and lower cost. The Advancing American Kidney Health initiative aims to increase the utilization of home therapies such as PD and kidney transplantation to treat end stage kidney disease (ESKD). A natural consequence of this development is that more patients will receive PD, and many will eventually undergo kidney transplantation. Therefore, it is important to understand the effect of pretransplant PD on posttransplant outcomes such as delayed graft function (DGF), rejection, thrombosis, graft, and patient survival. Furthermore, some of these patients may develop DGF, which raises the question of the utility of PD during DGF and its risks. Although transplant is the best renal replacement therapy option, it is not everlasting, and many transplant recipients must go on dialysis after allograft failure. Can PD be a good option for these patients? This is another critical question. Furthermore, a significant proportion of nonrenal solid organ transplant recipients develop ESKD. Is PD feasible in this group? In this review, we try to address all of these questions in the light of available evidence.

Environmental sustainability assessment of wooden furniture produced in Pakistan

Life cycle assessment was carried out for a conventional wooden furniture set produced in Mardan division of the Khyber Pakhtunkhwa province of Pakistan during 2018-19. Primary data regarding inputs and outputs were collected through questionnaire surveys from 100 conventional wooden furniture set manufacturers, 50 in district Mardan and 50 in district Swabi. In the present study, cradle-to-gate life cycle assessment approach was applied for a functional unit of one conventional wooden furniture set. Production weighted average data were modelled in the environmental impacts modelling software i.e., SimaPro v.8.5. The results showed that textile used in sofa set, wood preservative for polishing and preventing insects attack and petrol used in generator had the highest contribution to all the environmental impact categories evaluated. Total cumulative energy demand for wooden furniture set manufactured was 30,005 MJ with most of the energy acquired from non-renewable fossil fuel resources.

Kidney transplant outcomes among recipients with post-transplant hip or knee joint replacement surgery

Patients with end-stage renal disease (ESRD) are at a higher risk of needing hip or knee replacement (joint replacement) surgery due to the high prevalence of degenerative joint disease and other conditions. However, there remains a large debate about the timing of joint replacement surgery and whether it should be pre- vs post-transplant. We conducted a retrospective study analyzing all adult kidney transplant recipients (KTRs) at our university hospital who had undergone subsequent joint replacement between 2001 and 2017. Transplant-specific outcomes of acute rejection, death censored graft failure (DCGF), and patient death post-joint replacement surgery were outcomes of interest. Controls were selected at a 1:3 ratio based on the incidence density sampling of post-transplant interval. There were 101 KTRs in the joint replacement group and were compared with 281 controls. In the multivariate analysis, the need for joint replacement was not associated with acute rejection (HR: 1.59; 95% CI: 0.77-3.29; p = 0.21); DCGF (HR: 0.89; 95% CI: 0.49-1.60; p = 0.70) or patient death (HR: 0.84, 95% CI: 0.55-1.38, p = 0.42). In selected KTRs, joint replacement surgery was not associated with detrimental transplant-specific outcomes. This article is protected by copyright. All rights reserved.

Factors affecting sensitization following kidney allograft failure

Management of immunosuppression in a kidney transplant recipient with a failed allograft is complex; continuation carries infectious and metabolic risks, and discontinuation can lead to sensitization. We evaluated risk factors for sensitization in 89 kidney or simultaneous kidney-pancreas recipients, whose kidney transplant failed after 1/2013 and who were subsequently re-evaluated for kidney transplantation. Among recipients with pre graft failure cPRA <50%, calcineurin inhibitor (CNI) continuation (OR 0.11, p = 0.003) and steroid continuation (OR 0.17, p = 0.04) were associated with significantly lower odds of developing an absolute increase in cPRA of ≥50%. Each additional HLA mismatch was associated with OR of 2.16 (p = 0.02). CNI use was associated with OR of 0.09 (p = 0.001) for increase in cPRA to ≥80% if pre graft failure cPRA was <50%, and OR of 0.08 (p = 0.02) for increase in cPRA to ≥98% if pre graft cPRA was <80%. Anti-metabolites were continued more often among recipients who had a <50% increase (p = 0.006), however the association was lost on multivariate analyses. Weaning off immunosuppression and higher number of HLA mismatches are associated with greater likelihood of sensitization. While both CNI and steroid continuation conferred some protection against increase in cPRA, CNI continuation was the only factor protecting against becoming highly sensitized. This article is protected by copyright. All rights reserved.

Pleistocene paleodrainages explain the phylogeographic structure of Malaysian populations of Asian arowana better than their chromatic variation

Little is known about the genetic structure and phylogeography of Asian arowana (Scleropages spp.). Natural variation in body color has led to the informal distinction of chromatic varieties, but previous studies that attempted to genetically characterize these varieties did not comprehensively cover their geographical distribution. In Malaysia, about 10 drainage-restricted populations of Asian arowana are known that are currently classified into 2 species and 3 color varieties. In this study, we used 3 molecular markers to test 2 hypotheses explaining the relationships among 9 of these populations. The first hypothesis postulates that each color variety forms a monophyletic group, whereas the second hypothesis assumes that Pleistocene paleodrainages shaped the distribution of these populations. We found that the overall genetic variability is low within Asian arowana and that the green variety is non-monophyletic, with other varieties nested within. Instead, the populations of Malaysia belong to 3 genetic lineages that are allopatrically distributed. The ages and distribution of 2 of these lineages are consistent with past connections through paleodrainages, whereas the last lineage is restricted to Central Sarawak. Overall, our results reject the first hypothesis, demonstrating that the geographic origin of specimens is a better phylogenetic indicator than their body color. This study highlights the importance of Malaysia in the conservation of Asian arowana, because it is the only country in which populations of all 3 main genetic lineages occur.

Risk factors and outcomes of BK viremia among deceased donor kidney transplant recipients based on donor characteristics

INTRODUCTION

BK polyomavirus (BKV) is a common infection among kidney transplant recipients (KTR). Risk factors and outcomes based on donor characteristics remain largely unknown.

METHODS

In this study, we aimed to analyze the impact of donor factors through a paired kidney analysis. We included 289 pairs of adult deceased donor transplants (578 KTRs total); each pair had received kidneys from the same donor. Recipient pairs were divided into three groups: "no BK group" if neither KTR developed BK viremia (n = 336), "discordant" if the only one did (n = 176), and "concordant" if both did (n = 66). Acute rejection (AR), graft failure, and BK nephropathy (BKN) were outcomes of interest.

RESULTS

Donors in the concordant group were younger, had lower kidney donor profile index (KDPI), and were less likely to be donor after circulatory death (DCD). In multivariate analyses, KTRs who had a donor with a higher body mass index (BMI) (hazard ratio (HR): 0.97; 95% confidence interval (CI): 0.95-0.99; p = .009) were less likely to develop BKV. Concordance was not associated with AR (HR: 0.83; 95% CI: 0.51-1.34; p = .45), graft failure (HR: 1.77; 95% CI: 0.42-7.50; p = .43), or BKN (HR: 1.02; 95% CI: 0.51-2.03; p = .96).

DISCUSSION

Our study suggests lower donor BMI is associated with BKV infection, and concordance or discordance between paired kidney recipients is not associated with poor outcomes.

The clinical value of donor-derived cell-free DNA measurements in kidney transplantation

Early diagnosis is critical to minimizing the damage rejection can do to the transplanted kidney. Donor-derived cell-free DNA (dd-cfDNA) represents non-encapsulated fragmented DNA that is continuously shed into the bloodstream from the allograft undergoing injury, with a half-life of about 30 min. This article reviews the available evidence regarding the diagnostic value of dd-cfDNA in kidney transplantation, as a result of which two assays, Allosure and Prospera, have garnered Medicare approval. We provide information on important scenarios and contexts including antibody-mediated rejection, T-cell mediated rejection, pre-test probability of rejection, timing of the test, repeat transplants, and background cell-free DNA levels to help our understanding of the test characteristics and utility of these assays in clinical practice. Data on multimodality assays including gene expression profiles and serial monitoring of dd-cfDNA in high risk situations are emerging.

Frailty in Pancreas Transplantation

There are a variety of definitions and criteria used in clinical practice to define frailty. In the absence of a gold-standard definition, frailty has been operationally defined as meeting 3 out of 5 phenotypic criteria indicating compromised function: low grip strength, low energy, slowed walking speed, low physical activity, and unintentional weight loss. Frailty is a common problem in solid organ transplant candidates who are in the process of being listed for a transplant, as well as after transplantation. Patients with diabetes or chronic kidney disease (CKD) are known to be at increased risk of being frail. As pancreas transplantation is exclusively performed among patients with diabetes and the majority of them also have CKD, pancreas transplant candidates and recipients are at high risk of being frail. Sarcopenia, fatigue, low walking speed, low physical activity, and unintentional weight loss, which are some of the phenotypes of frailty, are very prevalent in this population. In various solid organs, frail patients are less likely to be listed or transplanted and have high waitlist mortality. Even after a transplant, they have increased risk of prolonged hospitalization, readmission, and delayed graft function. Given the negative impact of frailty on solid organ transplants, we believe that frailty would have a similar or even worse impact on pancreas transplantation. Due to the paucity of data specifically among pancreas transplant recipients, here we include frailty data from patients with CKD, diabetes, and various solid organ transplant recipients.

Cytomegalovirus nephritis in kidney transplant recipients: Epidemiology and outcomes of an uncommon diagnosis

BACKGROUND

Data on epidemiology and outcomes of cytomegalovirus (CMV) nephritis in kidney transplant patients are limited due to the rarity of this condition.

METHODS

A retrospective review of all kidney transplant recipients (KTR) (n = 6490) and biopsy-proven CMV nephritis between 1/1997 and 12/2020 was performed.

RESULTS

The prevalence of CMV nephritis was low: 13/6490 (0.2%). The diagnosis was made at a median of 7.0 months (range 2.6-15.6 months) after transplant. 6 of 13 (46%) patients were CMV (D+/R-). Median CMV DNA load at biopsy was 376,000, IU/mL (range 87,000-6,460,000 IU/mL). Main biopsy features were CMV glomerulitis (n = 7/13, 54%) followed by CMV tubulointerstitial nephritis (6/13; 46%). Mean eGFR at biopsy (22.7 ± 12 mL/min/1.73 m² ) was significantly decreased compared to baseline eGFR (38.7 ± 18.5 mL/min/1.73 m² , p = 0.02). The vast majority, 11 of 13 (85%), experienced graft failure including 5 of 13 (38%) death-censored. 5 of 13 (38%) patients were diagnosed with acute rejection: three had concurrent acute rejection, and two had rejection within 3 months of index biopsy, respectively. Patients with tubulointerstitial CMV nephritis were significantly more likely to have rejection at the time of biopsy (50% vs. 0%, p < 0.05) compared to those with glomerular CMV nephritis. There were no significant differences between these groups in terms of eGFR at all time points, death, graft failure, immunosuppression changes or rejection after biopsy.

CONCLUSION

CMV nephritis is rare but appears to be associated with poor patient/allograft outcomes. Early identification and timely treatment of CMV infection may prevent end-organ involvement and improve patient and allograft-related outcomes.

Transplant kidney biopsy for proteinuria with stable creatinine: Findings and outcomes

INTRODUCTION

Little is known aboutbiopsy findings and outcomes when kidney transplant recipients (KTRs) undergo biopsy for isolated proteinuria with stable serum creatinine (SCr).

METHODS

We analyzed all KTRs who underwent biopsy for isolated proteinuria with stable SCr between January 2016 and June 2020. Patients were divided into three groups based on the biopsy findings: Active Rejection (AR), Glomerulonephritis (GN), and Other.

RESULTS

A total of 130 KTRs fulfilled our selection criteria; 38 (29%) in the AR group, 26 (20%) in the GN group, and 66 (51%) in the Other group. Most baseline characteristics were similar between the groups. In multivariate analysis, higher HLA mismatch (HR per mismatch: 1.30; 95% CI:1.06-1.59; P = .01) and male gender (HR: .45; 95% CI .23-.89; P = .02) were associated with AR. There was no significant correlation between the degree of proteinuria and rejection (r = .05, P = .58) or GN (r = .07, P = .53). Graft survival was also similar between the groups. Likely due to the early diagnosis without a significant rise in SCr, outcomes were similar among all three groups.

CONCLUSION

Routine monitoring for proteinuria followed by a biopsy and appropriate management may help to identify early acute graft injury and prevent graft failure.

Post-transplant erythrocytosis after kidney transplantation: A review

Post-transplant erythrocytosis (PTE) is defined as persistently elevated hemoglobin > 17 g/dL or hematocrit levels > 51% following kidney transplantation, independent of duration. It is a relatively common complication within 8 months to 24 months post-transplantation, occurring in 8%-15% of kidney transplant recipients. Established PTE risk factors include male gender, normal hemoglobin/hematocrit pre-transplant (suggestive of robust native kidney erythropoietin production), renal artery stenosis, patients with a well-functioning graft, and dialysis before transplantation. Many factors play a role in the development of PTE, however, underlying endogenous erythropoietin secretion pre-and post-transplant is significant. Other contributory factors include the renin-angiotensin- aldosterone system, insulin-like growth factors, endogenous androgens, and local renal hypoxia. Most patients with PTE experience mild symptoms like malaise, headache, fatigue, and dizziness. While prior investigations showed an increased risk of thromboembolic events, more recent evidence tells a different story-that PTE perhaps has lessened risk of thromboembolic events or negative graft outcomes than previously thought. In the evaluation of PTE, it is important to exclude other causes of erythrocytosis including malignancy before treatment. Angiotensin converting enzyme inhibitors (ACE-I) and angiotensin receptor blockers (ARBs) are the mainstays of treatment. Increased ACE-I/ARB use has likely contributed to the falling incidence of erythrocytosis. In this review article, we summarize the current literature in the field of post-transplant erythrocytosis after kidney transplantation.

Post-kidney transplant serum magnesium exhibits a U-shaped association with subsequent mortality: an observational cohort study

Hypomagnesemia is common in kidney transplant recipients (KTRs). We sought to explore the relationship between Mg and outcomes in KTRs, which may be associated with mortality and thus may be a potential intervention target to improve outcomes. We followed KTRs performed between 01/2000 and 6/2016 at a large US transplant center from 6 months post-transplant to graft failure, death, or loss to follow-up. Using Mg as a time-dependent variable, associations between Mg and outcomes any time after 6 months post-transplant were evaluated. 3680 KTRs with 50  413 Mg measurements met inclusion criteria. 657 deaths occurred over a median follow-up of 5.1 years. Compared to Mg of 1.5-1.8 mg/dl, both lower (HR 1.17, 95% confidence interval (CI): 1.07-1.28) and higher (HR 1.16, 95% CI: 1.09-1.23) Mg levels were associated with greater risk of mortality. Similar U-shaped associations were observed for Mg and cardiovascular disease-related mortality (HR for Mg ≤1.5 mg/dl: 1.31; CI: 1.03-1.68) and infection-related mortality (HR for Mg ≤1.5 mg/dl: 1.28; CI: 1.09-1.51), although relationships for Mg >1.8 mg/dl were not statistically significant. Mg exhibits a U-shaped association with mortality in KTRs, with levels between 1.5 and 1.8 mg/dl associated with the lowest risk.

Continuation of Peritoneal Dialysis in Adult Kidney Transplant Recipients With Delayed Graft Function

Introduction

Peritoneal dialysis (PD) has been used increasingly in past decade. Many of these patients undergo transplantation and may require dialysis for delayed graft function (DGF). The outcomes of DGF based on the post-transplantation dialysis modality are not well known.

Methods

We retrospectively reviewed all adult kidney transplant recipients (KTRs) from the University of Wisconsin School of Medicine and Public Health who developed DGF between November 2015 and April 2019. Patients were divided into those who received hemodialysis (HD) or PD during the DGF period. Immediate graft explant, DGF among living donor KTRs, or those requiring just a single dialysis treatment were excluded.

Results

Of 224 KTRs with DGF during the study period, 167 fulfilled our selection criteria. There were 16 patients in the PD and 151 in the HD group. Baseline characteristics were similar between the two groups, except diabetes was more prevalent in the HD group. Five of 16 PD patients had to be transitioned to HD. There was no difference in DGF duration, hospital length of stay, infectious or surgical complications, rejection at various time periods, graft function at last follow-up, or graft failure. In multivariate analysis, only rejection within the first year of transplantation (hazard ratio [HR]: 4.26; 95% confidence interval [CI]: 1.20-15.08; P = 0.02) and post-surgical complications (HR: 3.79; 95% CI: 1.03- 13.91; P = 0.04) were associated with death-censored graft failure (DCGF). The use of PD for treatment of DGF was not associated with DCGF.

Conclusions

In carefully selected patients, PD can be continued safely for DGF without any effect on short-term or long-term transplant outcomes.

Successful management of T-cell mediated rejection in a recent kidney transplant recipient with COVID-19 associated severe acute respiratory syndrome

COVID‐19‐associated vasculitis has been reported as a defining feature of systemic disease including acute kidney injury. However, the understanding of COVID‐19 kidney transplant‐related injuries is still evolving. We report a case of AKI with isolated vasculitis (v2 lesion) in a new kidney transplant recipient with COVID‐19 pneumonia.