bluuebunny/crossref_metadata_2025_split huggingface dataset:
#2055 Variations in free water transport condition ultrafiltration capacity since basal times
Authors: Morales Byron Andrés Chiliquinga , Gomez Astrid Rodriguez , Montero Maria Elisa Casado , Varas Carmen Martin , Garcia Leonardo Calle , Gutiérrez Paulo García , Garrote Pablo Luis Sánchez , Alonso Carlos Santos , Losada Maria Nieves , Luis Maria Jose Fernandez-Reyes 
Published: May 2024

Abstract

Background and Aims
There is great variability in free water carrying capacity (FFWC) in incident patients, but the extent to which this variability impacts inherent ultrafiltration failure (UF) is unknown. The peritoneal equilibration test (PET) with 3.86% glucose allows measurement of permeability (D/Pcr), standard UF (UFs) and sodium screening (CriNa) as an indirect measure of TAL.
Our objectives were to determine to what extent variations in free water transport condition a related ultrafiltration failure. To assess, according to the variables studied, whether or not the patient`s comorbidities or anthropometric data influenced our study.

Method
We conducted a study in 58 incident patients in our hospital between 2009-2023 in which we evaluated D/Pcr, UFs and CriNa in PET -3.86. We recorded the dialysis pattern and daily UF.

Results
The PET -3.86% results were evaluated (Table 1), showing the clinical and peritoneal transport characteristics of the total patients and the comparison between patients with CriNa lower or higher than the median. The patients with lower CriNa were older and had lower UFs and UFd.
We found a correlation between CriNa and UFs (0.39, p = 0.002) and daily UF (0.318, p = 0.05).
In the multiple regression analysis, CriNa and D/Pcr maintain the correlation with UFs independently. While only CriNa maintains the correlation with daily UF, despite there being no differences in the use of DPA or icodextrin.

Conclusion
On analyzing the results, we found that the intrinsic variations of the membrane, in the free water transport capacity, justify part of the ultrafiltration capacity measured both in kinetics and daily ultrafiltration. As for age, we found that the older the patient is, the lower the sodium sieving, at least initially. With this study we emphasize the importance of assessing variations in free water transport capacity using the peritoneal equilibrium test as a tool.
#2368 GHRH levels and AhR expression in CKD patients before and after kidney transplantation
Authors: Hernandez Leah , Sartirana Elisa , Almoussaui Asrah , Arefin Samsul , Barany Franz Peter , Wennberg Lars , Witasp Anna , Cantaluppi Vincenzo , Stenvinkel Peter , Kublickiene Karolina 
Published: May 2024

Abstract

Background and Aims
Chronic kidney disease (CKD) is an irreversible decline in renal function where kidney transplantation (KT) is the optimal therapeutic intervention. We aim to investigate the role and activation of the uremic toxin receptor aryl hydrocarbon receptor (AhR) in the microvasculature, particularly its implication in the blood-brain barrier impairment. We will also explore the potential role of growth hormone-releasing hormone (GHRH) as a biomarker reflecting the resolution of uremia-induced inflammation, early vascular ageing (EVA) phenotype, and potential enhancement in central nervous system (CNS) function post-KT.

Method
Resistance arteries from KT patients and non-CKD controls were isolated and expression of AhR was analysed by immunohistochemistry. The study used plasma samples from 60 KT patients, and levels of GHRH were measured at baseline and two years after transplantation using ELISA.

Results
Following KT, our initial findings indicate a decrease in levels of DBP, Lp(a), creatinine, homocysteine, phosphate, and troponin T among KT patients. Conversely, there was an increase in albumin, HBA1c, calcium and NfL post-transplantation. The expression of AhR in the resistance arteries of KT patients (2.6%) was notably lower compared to non-CKD controls (9.7%). Plasma concentrations of GHRH were significantly higher (p &lt; 0.0001) in CKD-5 patients two years post-KT (2.94 ng/mL, IQR 2.60-3.43) compared to baseline (2.32 mg/L, IQR 1.84-3.24). This elevated trend in GHRH levels post-KT was observed in both sexes, with males (p &lt; 0.0001) and females (p 0.0084) showing higher levels—males (3.0 ng/mL, IQR 2.6-3.5) and females (2.8 ng/mL, IQR 2.4-3.5)—compared to baseline level of males (2.4 ng/mL, IQR 1.8-3.2) and females (2.2 ng/mL, 1.9-3.3). No significant difference in GHRH levels was observed when assessing extreme EVA phenotypes based on the presence or absence of calcification or fibrosis.

Conclusion
Contrary to our initial expectation, the preliminary results indicate a downregulation in AhR expression within resistance vessels of CKD patients, implying modifications in AhR signaling within the uremic environment. The observed alteration in GHRH levels presents a promising avenue for further investigation focusing on its possible application as a biomarker for assessing CNS status in CKD patients undergoing KT. Prospective clinical application could involve the administration of GHRH agonists as a protective measure against cognitive impairment, considering its deficiency in CKD. Such supplementation holds promise to prevent further cognitive morbidity. The modulation in the levels of this hormone has the potential to significantly influence the treatment trajectory of CKD patients and enhance clinical outcomes.
#2314 Circulating immune complexes concentration and complement activation in sensitized kidney transplant recipients
Authors: Trivyza Maria Styliani , Tsakas Sotiris , Ntrinias Theodoros , Georgopoulou Georgia Andriana , Perdiki Panagiota , Papasotiriou Marios , Papachristou Evangelos , Goumenos Dimitrios 
Published: May 2024

Abstract

Background and Aims
Chronic antibody mediated rejection of the kidney transplant is the most common cause of graft loss in the late posttransplant period. Crucial in this process seems to be the role of classical pathway complement activation due to the formation of immune complexes. The formation of immune complexes is a benign process of a normally functioning immune system. In kidney transplant recipients (KTRs), the production of donor specific IgG/IgM antibodies (DSAs) against donor antigens (MHC molecules, ABO blood group antigens) leads to the attachment of immune complexes to cell membranes and subsequent tissue damage through complement activation. The attachment of C1q complement fragment to the immune complexes holds an important part in this process. This study aims to determine the levels of immune complexes as well as classical pathway complement activation in sensitized kidney transplant recipients.

Method
In this cross-sectional study 3 groups of KTRs were compared as to the levels of immunocomplexes concentration and classical pathway complement activation. Fourteen KTRs with preformed or de novo donor specific antibodies were compared to 28 kidney transplant recipients with no DSAs and to 22 subjects with no history of chronic kidney disease (controls). We used MicroVue Complement CIC-C1q EIA that is designed to detect immunocomplexes that bind to C1q in human serum or plasma. In order to estimate total classical pathway complement activation in serum, we used MicroVue Complement CH50 Eq EIA.

Results
Kidney function (eGFR) of KTRs with and without DSAs was similar (53.1 ± vs. 60.8 ± ml/min/1.73 m2, p = 0.54) but lower in comparison to controls (106.4 ml/min/1.73 m2, p &lt; 0.001). We found a significantly higher concentration of C1q-immunocomplexes in the serum of KTRs with donor specific antibodies, in comparison to controls, as well as to the group of kidney transplant recipients with no DSAs (6.78 ± 2.7 vs. 4.83 ± 1.9 vs. 5.04 ± 1.2 μgEq/ml respectively, p = 0.0078). Furthermore, there was no significant difference of C1q-immunocomplexes between kidney transplant recipients with no DSAs and controls. Finally, a significant reduction of CH50 levels was observed in KTRs with DSAs as compared to controls and KTRs with no DSAs (39.2 ± 14.9 vs. 70.6 ± 34.3 vs. 67.9 ± 39.9 U/ml respectively, p = 0.003), which suggests higher levels of classical pathway complement activation. CH50 levels in KTRs with DSAs, who were further subcategorized in those with preformed and those with de novo DSAs were similar (39.68 ± 15.6 vs 39.08 ± 16.04 U/ml).

Conclusion
Kidney transplant recipients with donor specific antibodies have increased serum levels of immune complexes and increased classical pathway complement activation.
#1181 The relationship between renal ischaemia-reperfusion injury and circadian rhythm
Authors: Yamaguchi Misuhiro , Hitaka Yukihiro , Nakamura Kimihiko , Hiroyoshi Toshiya , Isoyama Naohito , Nagao Kazuhiro , Shiraishi Koji 
Published: May 2024

Abstract

Background and Aims
Kidney disease is a global health problem in which various aetiologies contribute to renal injury and dysfunction. Renal ischaemia-reperfusion injury (IRI) is a condition caused by early oxidative stress due to renal tissue ischaemia and a rapid immune response after reperfusion. Circadian rhythms are important regulators of metabolism and their disruption can lead to heart disease and fibrosis in various organs. Although recent reports have shed light on the impact of renal injury and disease on the renal circadian clock, the exact mechanisms by which circadian rhythm genes contribute to the progression of renal dysfunction in IRI and the onset of chronic kidney disease (CKD) are not fully understood.

Method
Male Wistar rats (8-9 weeks old, 250-280 g body weight) were used to establish the I/R model. To induce renal I/R injury, the left renal artery was clamped for 30 or 45 min and then removed to restore blood flow. Simultaneously, nephrectomy of the right kidney was performed; renal tissue and blood were collected 14 days after I/R. HE staining, Sirius red staining and immunostaining (F4/80 staining) were performed. Kidney tissue was RNA-seq'd and qPCR'd for circadian rhythm genes and fibrosis genes involved in kidney failure that were altered by I/R. Kidney tissue was also RNA-seq'd and qPCR'd for circadian rhythm genes and fibrosis genes involved in kidney failure. We also established an in vitro hypoxia-reoxygenation (H/R) model using single cell RPTECs and performed qPCR and Western blotting.

Results
In the IRI rat group, the expression of circadian repressor genes Nr1d1 and Nr1d2, which are important for reducing inflammation, decreased, while the expression of Bmal1 and Cry1, which regulate renal deterioration, increased. Using RNA-seq, we also identified the involvement of the TGFβ pathway in linking the circadian clock to kidney injury and fibrosis, and observed similar results in the H/R group using RPTEC cells in vivo.

Conclusion
Fibrosis and circadian rhythms were found to be closely related in renal IRI. The findings described here may help in the development of new therapeutic approaches to ameliorate the effects of renal IRI and improve the outcome of kidney disease, including kidney transplantation, offering hope to patients worldwide.
#1474 COVID-19-infection in kidney transplant recipients during the omicron surge, a sigh of relief
Authors: Dawar Rona , Wallquist Carin , Månsson Fredrik 
Published: May 2024

Abstract

Background and Aims
The COVID-19 pandemic had a profound impact on global health, particularly affecting high-risk individuals such as solid organ transplant recipients (SOTRs). SOTRs have an elevated risk of severe COVID-19 disease and increased mortality. Kidney transplant recipients (KTRs) vaccinated with mRNA-based vaccines exhibit a lower response rate and shorter half-time of the serologic conversion. However, the percentage of serologic response improves with increasing number of vaccine doses. Studies also indicate that KTRs with prior COVID-19 infection demonstrate a more robust immune response post-immunization compared to COVID-19 naïve patients. Factors such as age, immunosuppressive regimen, eGFR, time since transplantation also impact vaccination response. This study aims to investigate COVID-19 infection outcome and vaccination response among KTRs during the Omicron surge.

Method
This study is a retrospective single-center cohort study at the Department of Nephrology and Transplantation at Skåne University Hospital in Malmö, Sweden. KTRs infected with COVID-19 during the Omicron surge were included (January 2022 until August 2023).

Results
97 KTRs diagnosed with COVID-19 were included of whom 91 were vaccinated. In average, three doses of COVID-19-vaccine had been given to the patients. 67 KTRs showed seroconversion, 28 remained seronegative and the status of the remaining 2 KTRs was unknown. There was a significant association between lack of antibody production and mycophenolic acid (MPA) treatment (P = 0.019, Chi2 test), however the significance was not retained in a multivariate logistic regression analysis. Among the seroconverted (n = 67), 61 experienced mild infection, 5 moderate infection and 1 severe infection, according to the WHO clinical progression scale. In the seronegative group (n = 28), 25 had mild infection while the remaining three had moderate infection. The median time for viral clearance was examined in 79 KTRs and was 23 days (IQR 18-31). Immunosuppression was adjusted in 34% (n = 33) of cases. 2.1% (n = 2) of KTRs experienced graft rejection post infection.

Conclusion
While most patients experienced a mild infection, unlike during the first surges of the pandemic, the observed subsequent graft rejections emphasize the complexity of COVID-19´s potentially immunologic triggering effect and risk of graft loss in KTRs. The correlation between MPA treatment and a lower degree of serologic conversion after vaccination underscores the need for personalized immunologic follow up and treatment regimen in KTRs.
#515 The clinical utility of systematic screening using aortoiliac CT angiography before kidney transplantation
Authors: Nielsen Marie Bodilsen , Budtz-Lilly Jacob , Dahl Jonathan , Keller Anna , Jespersen Bente , Ivarsen Per , Winther Simon , Birn Henrik 
Published: May 2024

Abstract

Background and Aims
Several guidelines suggest screening for peripheral artery disease before kidney transplantation including the Kidney Disease: Improving Global Outcomes. There is currently no consensus on whom or how to screen for peripheral artery disease. We examined the clinical consequences of systematic screening using aortoiliac computed tomography (CT) angiography in a large cohort of potential kidney transplant candidates.

Method
In a retrospective study, potential kidney transplant candidates underwent aortoiliac CT angiography as pretransplant screening for peripheral artery disease. Screening criteria were patients above 40 years, and/or diabetes, and/or need for dialysis more than 5 years. The prevalence of clinically diagnosed peripheral artery disease and aortoiliac stenosis and calcification of iliac arteries at CT angiographies were assessed. A multidisciplinary team evaluated the CT angiographies in regard to transplantability and surgery planning.

Results
In total, 470 potential kidney transplant candidates were included. Clinically diagnosed peripheral artery disease was present in 14%, aortoiliac stenosis in 16%, and iliac circular calcifications in 21% potential kidney transplant candidates. A change in clinical decision by the multidisciplinary team was recorded in 67 of 429 (16%) patients due to vascular findings including choice of side for implantation in 52 (12%) and transplant-ineligibility in 7 (2%). Six out of seven ineligible patients had clinically diagnosed peripheral artery disease. Any clinical decision-making was recorded in 178 (41%).

Conclusion
Systematic screening using aortoiliac CT angiography may guide the planning of transplant surgery in a large proportion of patients. The effect of transplant outcomes remains to be established.
#1279 Efficacy and safety of non-vitamin K antagonist oral anticoagulants in renal transplant recipients with atrial fibrillation
Authors: Heleniak Zbigniew , Naik Marcel , Eleftheriadis Georgios , Ruszkowski Jakub , Halleck Fabian , Undas Anetta , Dębska-Ślizień Alicja , Budde Klemens 
Published: May 2024

Abstract

Background and Aims
Atrial fibrillation (AF) is associated with increased stroke and bleeding risk in patients with chronic kidney disease (CKD) including renal transplant recipients (RTRs). Little is known about the real-life use of non-vitamin K antagonist oral anticoagulants (NOACs) in RTRs.

Method
In a retrospective cohort study conducted in one academic transplant center, we enrolled consecutive 168 RTRs with AF on NOACs including 139 (82.7%) subjects on apixaban 5 or 10 mg/day, 18 (10.7%) on rivaroxaban 15 or 20 mg/day, 6 (3.6%) subjects on edoxaban 30 mg/day and 5 patients (3.0%) firstly treated with rivaroxaban and then switched to apixaban. Thromboembolic (stroke, transient ischemic attack, systolic embolism) and bleeding events (major and clinically relevant non-major bleeding) were recorded during a median follow-up of 21.2 months. There were no significant differences in demographic, clinical, and laboratory variables at baseline between the 3 treatment groups (Fig. 1).

Results
During follow-up, arterial thromboembolic events occurred in 9 (6.3%) subjects on apixaban and 4 (18.2%) on rivaroxaban. Patients treated with rivaroxaban did not have a significantly higher hazard of arterial thromboembolic events when compared with those on apixaban (hazard ratio [HR] 2.04; 95% CI: 0.68-6.12, p=0.21).
Major bleeding or clinically relevant non-major bleeding occurred in 17 (11.8%) patients receiving apixaban (one experienced both events), 3 (13.0%) patients on rivaroxaban, and 2 (33.3%) on edoxaban. When compared to apixaban, the other NOACs did not significantly differ in the hazard of bleeding [rivaroxaban: HR 0.79 (95% CI: 0.24-2.58; p=0.69); edoxaban: HR 1.90 (95% CI: 0.35-10.27; p=0.46)].

Conclusion
The study suggests that RTRs with AF receiving apixaban and rivaroxaban have a similar risk of thromboembolism and bleeding in the everyday practice of the academic transplantation center. Edoxaban was rarely chosen in this group of patients, therefore evidence is uncertain.
#601 Overweight-obese kidney transplant recipients have altered tacrolimus clearance and need lower doses for target levels with good graft outcomes
Authors: Elsharkawy Magdy , Elbraky Abdelrahman , Abdelmegied Shaimaa Zaki 
Published: May 2024

Abstract

Background and Aims
CYP3A4 which has been associated with altered tacrolimus (Tac) clearance. Clearances for drugs that are CYP3A4 substrates are generally reduced by 10%-35% in obese compared to normal-weight individuals. This study assessed the early and late Tac levels and weight-based total daily dose (TDD) for target Tac level in overweight-obese kidney transplant (KT) recipients and its relation to graft outcomes.

Methods
A retrospective study included 62 live-related KT recipients: overweight-obese KT recipients (N=32) with body mass index (BMI) &gt;25 and normal-weight KT recipients (N=30) with BMI &lt;25. The Tac level and weight-based TDD were examined in the 1st 3 months and 1 year after kidney transplantation with assessment of graft outcome.

Results
The overweight-obese patients' mean BMI was 31.29 and normal-weight patients' mean BMI was 22.20 p-value (0.0001). There was no significant difference between overweight-obese patients and normal-weight patients in mean Tac levels in 1st 3 months and after 1-year (mean 8.902, 6.99 ng/ml versus 8.906, 6.91 ng/ml respectively) p-values (0.992, 0.850) respectively. The weight-based TDD for target Tac level in 1st 3 months and after 1-year was significantly lower in overweight-obese than normal-weight patients (mean 0.108, 0.073 ng/ml versus 0.167, 0.102 ng/ml) respectively with p-value (0. 00035, 0.0076) respectively. KT recipients with BMI &gt;30 showed lower weight-based TDD versus KT recipients with BMI 25-30 in 1st 3 months (0.094 versus 0.131 ng/ml) p-value (0.0255) while no difference after 1-year p-value (0.353). Graft outcomes did not significantly differ between overweight-obese versus normal-weight patients; the mean serum creatinine (1.22 versus 1.27 mg/dl) p-value (0.680) and graft rejection was (6 patients versus 6 patients) p-value (0.104) without graft loss. The weight-based TDD after 1-year was negatively correlated with BMI and transplant duration {r −0.369, p 0.003, r −0.278, p 0.028} respectively.

Conclusion
Overweight-obese patients have altered Tac clearance and they need lower doses to achieve target Tac level in the early and late periods post-transplant which is linked to good graft outcomes. According to these preliminary data the department is planning to study the effect of CYP 3A4/5 genetic polymorphisms on Tac dose requirement in most of these patients.
#2635 A prospective cohort study of sodium-glucose cotransporter 2 inhibitor-treated glomerulonephritis in kidney transplant patients
Authors: Kwon Hyukyong , Son Sung Hyun , Park Youngchan , Jeong Joon Heun , Yoon Chul Soo , Hwang Eun Joo , Kim Sun , Kong Jin Min 
Published: May 2024

Abstract

Background and Aims
Recurrent or de novo glomerulonephritis (GN) after kidney transplantation (KT) is one of the main causes of renal allograft failure without effective treatment. Recent randomized controlled trials have demonstrated the beneficial effects of sodium-glucose cotransporter 2 inhibitors (SGLT2i) in delaying the progression of chronic kidney disease of broad range, including GN.

Method
We conducted a single-center, prospective study on the treatment with SGLT2i in 24 patients with biopsy-proven GN of renal allograft. IgA nephropathy was the most frequent (n=16), followed by focal segmental glomerulosclerosis (n=2), membranous nephropathy (n=2) and others (n=4). Baseline mean eGFR was 58 ± 26 mL/min/1.73 m2. The primary outcome is the change in proteinuria from baseline to 6 and 12 months, and the change in eGFR slope before (−24 to 0 months) and after (3 to 15 months) the initiation of SGLT2i. The secondary outcome is the change in body weight (BW), systolic blood pressure (SBP) and doses of antihypertensives. Adverse reactions were closely observed.

Results
The post-SGLT2i follow-up period was 17.5 (median) ± 14.9 months. The eGFR slope improved from −4.762 ± 1.29 ml/min/1.73 m2/year(before SGLT2i) to −0.667 ± 4.07 (after SGLT2i). The urinary protein-creatinine ratio did not change significantly. BW decreased significantly at 3 months and maintained thereafter. SBP did not change significantly, but the number of antihypertensives decreased. There was no cases of acute pyelonephritis or AKI due to volume depletion.

Conclusion
SGLT2i slowed the eGFR decline of patients with GN of renal allograft and was well-tolerated. Our preliminary results warrant confirmation by further studies with a larger number of patients and prolonged follow-up.