bluuebunny/crossref_metadata_2025_split huggingface dataset:
MO919: Persistence of Antibodies After SARS-COV-2 Vaccines in Haemodialysis Patients: A 6 Months Follow-Up
Authors: Murt Ahmet , Riza Altiparmak Mehmet , Pekpak Meltem , Ataman Rezzan 
Published: May 2022

Abstract

BACKGROUND AND AIMS
As COVID-19 related mortality is higher in haemodialysis patients than in the general population, proper vaccination strategies against the SARS-CoV-2 virus have utmost importance. It has been previously shown that mRNA vaccines (e.g. BNT162b2) can generate &gt;95% of seropositivity in haemodialysis patients [1]. On the other hand, the seropositivity rate reached by the inactivated vaccine (CoronaVac®) was around 80%. In this study, we aimed to analyse the persistence of SARS-CoV-2 antibodies in haemodialysis patients for 6 months and compare it with the healthy controls.

METHOD
Haemodialysis patients who were vaccinated either by BNT162b2 or CoronaVac® and who continued their regular controls for 6 months were involved in the study. Those who had previous or active SARS-CoV-2 infection, who had malignancies and those who had received immunosuppressive drugs in the previous 12 month were excluded from the study. SARS-CoV-2 IgG levels were measured by a commercial test after the first doses of the vaccines and at the end of the sixth month. Healthy healthcare workers who were vaccinated with similar vaccine schemes were taken as the control group.

RESULTS
We recruited 85 haemodialysis patients who had received their first doses of either vaccine. Of them, 4 patients died; 3 patients were hospitalized because of COVID-19 infection during the follow-up; 9 patients missed at least one of their regular controls; and 2 patients were diagnosed with malignancy. A total of 26 patients experienced asymptomatic or mild COVID-19 infection during the follow-up period. SARS-CoV-2 IgG levels were measured at the end of the sixth month for the remaining 41 patients. Sero-positivity significantly decreased at the end of the sixth month for both vaccines, but the BNT162b2 group (n = 22) still had better seropositivity than CoronaVac® (n = 19) group (81% versus 50%; P = .03). In contrast, the seropositivity of healthy controls, even with the inactivated vaccine, was 96%. When one booster dose was applied, 90% of seropositivity could be maintained in the BNT162b2 group at the sixth month.

CONCLUSION
BNT162b2 vaccine generates more persistent antibodies than inactivated vaccines in haemodialysis patients. However, when compared with the healthy controls at the end of the sixth month, antibody titers decrease more profoundly in haemodialysis patients. The booster dose can maintain the antibody levels and should be applied at least every 6 months.
MO920: SARS-COV-2 Neutralizing Antibody Response to Booster Vaccination in Patients on Hemodialysis
Authors: Wang Xiaoling , Han Maggie , Wang Kevin , Thwin Ohnmar , Rivera-Fuentes Lemuel , Haq Zahin , Grobe Nadja , Wang Yuedong , Kotanko Peter 
Published: May 2022

Abstract

BACKGROUND AND AIMS
SARS-CoV-2 antibody titers after two doses of vaccination decrease over time. Hemodialysis patients are especially vulnerable to COVID-19 as they are immunocompromised, putting them at higher risk of infection and poorer response to vaccines. Therefore, administrating the third dose (‘booster’) in these patients is key to reduce COVID-19 infections and prevent severe illness. Dialysis patients were among the first group of patients who received booster vaccinations. To study the humoral response to the third injection in this group, we collected serum from 33 patients on hemodialysis and measured neutralizing antibody titers against SARS-CoV-2 before and after their booster doses.

METHOD
Patients were recruited from a dialysis center in New York City, NY from June to September 2021. Data on COVID-19 vaccination and demographics were collected upon enrollment. Blood samples were taken after enrollment. SARS-CoV-2 neutralization antibodies were assayed using the GenScript SARS-CoV-2 Surrogate Virus Neutralization Test Kit (Cat#L00847-A). Corresponding neutralizing antibody titers are presented as Unit/mL (U/mL).

RESULTS
A total of 33 in-center hemodialysis patients who had received three doses of vaccination were studied. Patients had a mean age of 61 years, 23 (70%) were male. Out of these, 31 (94%) patients received three doses of mRNA-1273 (Moderna), and two patients received the BNT162b2 (Pfizer BioNTech) vaccine. A total of 138 serum samples were analyzed (ranging from 156 days before to 85 days after the booster). Figure 1 shows the antibody titer distribution of all samples in these 33 patients. Each color indicates an individual patient. Each patient has up to 12 data points before and after the booster. The mean neutralizing antibody titers of all 48 data points pre-booster is 29.291 U/mL (range: 228–188.600). Seven days post-booster, the mean neutralizing antibody titer is 73.088 U/mL (range: 12.401–254.504). Mean titer is 169.826 U/mL (range: 17.830–375.046) at 14–28 days post-booster. After the peak time, we observe a decline of the titers. At 72–85 days, the mean titer is 72.179 (range: 33.702–204.382).
We fitted a nonparametric mixed effects model with an adaptive spline and a random intercept for each subject to neutralizing antibody titers on the log10 scale. The estimate of the mean trajectory and its 95% confidence interval are shown in Fig. 2. The estimated peak time is 18.2 days with a 95% confidence interval (0–27.7).

CONCLUSION
Our results suggest that hemodialysis patients have a strong humoral response to booster vaccination. Neutralizing antibody titers peak at 18 days post-booster and wane to an average of 42% of peak value after 10–12 weeks.
MO922: Intradialytic Plantar Electrical Nerve Stimulation During Routine Hemodialysis Process Facilitate Physical Activities of Daily Life in Adults With Diabetes and End-Stage Renal Disease––A Randomized Double-Blinded Controlled Trial
Authors: Hamad Abdullah , Al-Ali Fadwa , Kinker Mishra Ram , Ibrahim Rania , Mathew Mincy , Ateya Heba , Yahya Mohamed , Khan Saifatullah , Talal Talal , Najafi Bijan 
Published: May 2022

Abstract

BACKGROUND AND AIMS
Reduced physical activity in daily life is a persistent problem in patients undergoing hemodialysis (HD). Although exercise could be beneficial, factors such as post-dialysis fatigue, time limitation and severe frailty may result in poor compliance. We are exploring an alternative therapy using intradialytic plantar electrical nerve stimulation (IPENS) provided during the routine hemodialysis process to address this gap.

METHOD
A total of 20 participants undergoing hemodialysis (age = 55 ± 2.7 years, BMI = 30.6 ± 1.3 kg/m2 female = 31%) were randomly assigned to the intervention group (IG), and 18 participants (age = 56 ± 2.2 years, BMI = 32.2 ± 1.2 kg/m2 female = 41%) were assigned to the control group (CG). The IG received 1-h IPENS during the routine hemodialysis process (three sessions/week) for 12 weeks. The CG received an identical but non-functional device for the same period. Participants and therapy-providers were blinded to the group allocation. Daily life physical activity was assessed remotely at baseline and every 12 week using a pendant wearable. To determine the effect of intervention, we estimated Cohen's effect size d. In addition, time effects, group and time × group effects were estimated using a general linear model.

RESULTS
We observed a significant increase in (Cohen's d = 0.97, P &lt; 0.01) number of postural transitions, (d = 0.71, P = 0.04) daily step counts and (d = 0.73, P = 0.03) episodes of walking due to IPENS. All participants in the IG tolerated the IPENS and completed all therapy sessions, indicating the feasibility.

CONCLUSION
These are early results related to IPENS therapy's feasibility and effectiveness to improve mobility among individuals undergoing routine hemodialysis. We can recommend routine IPENS therapy as a practical alternative for those who may not engage in routine exercise programs if the results will be held in the larger sample.
MO932: Same But Different? Covid-19 Metabolome in Hemodialysis
Authors: Schuller Max , Oberhuber Monika , Prietl Barbara , Zügner Elmar , Prugger Eva-Maria , Magnes Christoph , Eller Kathrin 
Published: May 2022

Abstract

BACKGROUND AND AIMS
The ongoing coronavirus disease 2019 (COVID-19) pandemic presents a major health and economical challenge. Chronic kidney disease (CKD) patients on haemodialysis (HDp) are at a particularly high risk of severe and fatal courses [1]. The COVID-19 metabolome is distinct [2] and may harbour potential prognostic markers and therapeutic targets. However, the metabolome in SARS-CoV-2 infected HDp remains unstudied.

METHOD
Untargeted and targeted metabolomics via high-performance liquid chromatography and tandem mass spectrometry of EDTA-plasma were performed in 39 individuals without CKD (non-HDp) and 41 HDp. Individuals were further grouped according to COVID-19 disease status and severity: negative, asymptomatic/mild (no or mild symptoms) and moderate/severe (requiring hospitalization).

RESULTS
Principal component analysis shows a clear separation of non-HDp and HDp alongside PC2, independent of COVID-19. Non-HDp with moderate/severe courses are shifted to the right of PC1. The influence of COVID-19 is less pronounced in HDp (Figure 1). Free fatty acids are main contributors to PC1, whereas PC2 reflects the complex metabolic disarray as seen in uraemia (Table 1).

CONCLUSION
Our data underlines the fundamental metabolic differences between non-HDp and HDp [3]. Furthermore, moderate/severe COVID-19 leads to a distinct metabolite signature in non-HDp. This effect is less pronounced in HDp, which could be indicative of a decreased capability to adapt to infectious challenges. In summary, these findings warrant caution when extrapolating COVID-19 metabolomics from otherwise healthy individuals, as the validity of prognostic markers and/or effectiveness of therapeutic approaches based on the metabolome may be limited in HDp.
MO939: Role of The General Practitioner in Promoting Organ Donation
Authors: Afifi Rania , Rostoum Soukaina , Berrada Omar , Mtioui Naoufal , Elkhayat Selma , Zamd Mohamed , Medkouri Ghislaine , Ramdani Benyouns , Benghanem Mohamed , Jandou Issam , Alafifi Mahmoud , Moataz Amine , Dakir Mohammed , Debbagh Adil , Aboutaieb Rachid 
Published: May 2022

Abstract

BACKGROUND AND AIMS
Organ transplants now play a significant role in the treatment of diseases that are nonetheless fatal. Organ and tissue transplantation in Morocco is severely delayed, and the number of transplants conducted in our country does not reach 10 per million inhabitants per year. Due to a scarcity of organs and tissues, the number of transplants and tissue grafts, which are primarily a Ministry of Health effort, is limited.
The main link in the medical chain is the general practitioner. In addition to his solitary practice of medicine, he is already responsible for a number of public health missions, primarily in the fields of disease prevention and detection, as well as organ and tissue donation promotion.
We conducted a quantitative cross-sectional study through a survey to measure the level of involvement and dedication of general practitioners in the promotion of organ donation.

METHOD
A quantitative descriptive cross-sectional study, based on a questionnaire with 20 closed questions, self-administered, emailed, completed anonymously and voluntarily intended to the general practitioner of the region of Casablanca. Questionnaire data were collected, encoded and analyzed using SPSS-PC (Version 21.0).

RESULTS
Our study targeted 200 general practitioners in total, of which 165 responded to the questionnaire, giving an overall response rate of 82.5%.
The average age of participants was 34.22. The duration of exercise varied between 1 and 40 years, with an estimated average of 11 years, 65% of the doctors practiced in the urban environment and ∼59.5% worked in the liberal sector.
A total of 87% of the doctors questioned were in favor of organ donation, and 13% were against organ donation, for which the religious cause represented 78% and 16% refused for medical reasons, 54.5% of them had never discussed the subject with their relatives, and 80.5% of practitioners declared having a patient waiting or who had received an organ transplant. Only 38% of doctors had already discussed this subject with their patients, of whom &gt;64% were following the sole initiative of the patient himself, and in none of the cases was awareness raising through posters in the waiting room.
Only 1.5% of participants had brochures on organ donation in their waiting rooms, and &gt;87% thought that TV shows in waiting rooms were a good means of information and awareness.

CONCLUSION
The involvement of general practitioners begins at the awareness stage, with the goal of disseminating information about organ donation.
MO942: Regulatory T and B Cell Responses are Equally Compromised During Antibody-Mediated Rejection of Kidney Allografts
Authors: Louis Kevin , Fadakar Paul , Macedo Camila , Yamada Masaki , Zeevi Adriana , Randhawa Parmjeet , Lefaucheur Carmen , Metes Diana 
Published: May 2022

Abstract

BACKGROUND AND AIMS
Although considerable advances have been made in understanding the cellular effector mechanisms responsible for donor-specific antibody (DSA) generation leading to antibody-mediated rejection (ABMR), the identification of cellular regulators of such immune responses is lacking.

METHOD
In a cohort of 96 kidney transplant recipients, we used high-dimensional flow cytometry to concomitantly profile and track the two major subsets of regulatory lymphocytes in the blood: T regulatory (TREG) and transitional B (TrB) cells. Additionally, we established co-culture assays to address their respective capacities to suppress antibody responses in vitro.

RESULTS
TREG and TrB were potent suppressors of T follicular helper-mediated B cell differentiation into plasmablast and antibody generation. While TREG and TrB were both durably expanded in patients who did not develop DSA post-transplant, patients who manifested DSA and progressed to ABMR displayed a marked and persistent numerical reduction in TREG and TrB cells. Strikingly, specific cell clusters expressing the transcription factor T-bet were selectively depleted in both TREG and TrB compartments in patients with ABMR. Importantly, the coordinated loss of these T-bet + CXCR5+ TREG and T-bet+CD21–TrB cell clusters was correlated with increased and inflammatory DSA responses, more extensive microvascular inflammation and a higher rate of kidney allograft loss.

CONCLUSION
Our study identified coordinated and persistent defects in the regulatory T and B cell responses in patients undergoing ABMR, which may contribute to their loss of humoral immune regulation and thus warranting timely therapeutic interventions to replenish and sustain TREG and TrB cells in these patients.
MO943: Levels of Forkhead Box P3 (FOXP3) Transcripts in Kidney Transplant Recipients is Associated With Post-Transplant Cytomegalovirus Viremia
Authors: Saleh Qais , Rasmussen Marianne , Nagarajah Subagini , Tepel Martin 
Published: May 2022

Abstract

BACKGROUND AND AIMS
The forkhead box P3 (FOXP3) transcription factor is essential for the differentiation of T regulatory cells, which are major regulators of immune tolerance and immunologic activity. Quantification of the FOXP3 mRNA in peripheral blood might be clinically useful. Considering possible post-transcriptional regulation of FOXP3 mRNA, we tested the hypothesis that a low level of FOXP3 is associated with a higher risk of cytomegalovirus (CMV) viremia, in kidney transplant recipients (KTRs).

METHOD
Blood samples were collected the first day after transplantation from incident adult kidney transplant recipients. Ribonucleic acid was extracted from peripheral blood mononuclear cells and used in quantitative reverse transcription polymerase chain reaction. Levels of FOXP3 were measured using two primers differentiating mRNA FOXP3 and pre-mRNA FOXP3 (pre-FOXP3), both primers were normalized to the reference gene β-actin. We defined viremia with CMV as the finding of more than 1000 copies per mL of CMV DNA in plasma, at least once, within 3 months after transplantation. A ratio of FOXP3 to pre-FOXP3 was calculated and compared, using Mann–Whitney U-test according to CMV viremia status. Finally using receiver operating characteristics, we calculated are under the curve.

RESULTS
Of 340 patients enrolled, 24 experienced post-transplant CMV viremia. The median ratio of FOXP3 to pre-FOXP3 was lower in those diagnosed with post-transplant CMV viremia, compared to those who were not 6.8 [1.2–11.3] versus 12.2 [3.5–28.9] P &lt; 0.01, respectively. Receiver operating characteristics yielded an area under the curve of 66.7% P &lt; 0.01.

CONCLUSION
Our data shows an association between low levels of FOXP3 and risk for post-transplant CMV infection in kidney transplant recipients.
MO944: Persistent Microscopic Hematuria At Kidney Donor Screening and Long-Term Post-Donation Kidney Outcomes
Authors: Van Der Weijden Jessica , Van Londen Marco , Pol Robert , Sanders Jan-Stephan , Navis Gerjan , Nolte Ilja , De Borst Martin , Berger Stefan P 
Published: May 2022

Abstract

BACKGROUND AND AIMS
According to current guidelines, a kidney biopsy is indicated in prospective living kidney donors with persistent microscopic hematuria and negative urological work-up. We investigated whether persistent microscopic hematuria at donor screening is associated with changes in post-donation eGFR, proteinuria, or blood pressure.

METHOD
We included 701 living kidney donors who underwent two urinalyses before donation and had annual evaluation of estimated glomerular filtration rate (eGFR), protein:creatinine ratio (PCR) and systolic blood pressure (SBP). The association between pre-donation persistent microscopic hematuria (≥ 1 red blood cell per high power field or ≥3 red blood cell per µL) and outcomes was assessed using generalized linear mixed models.

RESULTS
Mean age was 52 ± 11 years, median [interquartile range] follow-up time was 5 [2–8] years. Pre-donation persistent microscopic hematuria was present in 88 donors (80% female, versus 45% in non-hematuria group, P &lt; 0.001). There were no significant associations between persistent microscopic hematuria at screening and course of eGFR [0.44 mL/min/1.73 m2 increase/year for hematuria donors versus 0.34 mL/min/1.73 m2 increase/year for non-hematuria donors (P = 0.65)], PCR (0.02 versus 0.04 mg/mmol increase/year, P = 0.38), or SBP (1.42 versus 0.92 mmHg increase/year, P = 0.17) post-donation, even after adjusting for pre-donation age, sex, body mass index, eGFR, PCR, SBP and ACE inhibitor/angiotensin receptor blocker use. Sensitivity analyses in subgroups with risk-factor(s) of kidney disease and subgroups with poorer post-donation courses of the outcomes yielded similar results.

CONCLUSION
Donors with persistent microscopic hematuria at donor screening had no increased risk of progressive eGFR decline, proteinuria, or hypertension. Despite the limitation of potential selection bias, it seems safe to allow donors with persistent microscopic hematuria without other risk factors to donate without prior kidney biopsy. However, these results warrant validation on the longer term after donation.
MO948: Impact of DE Novo Immunosuppression in The Covid-19 Serological Status at Kidney Transplantation
Authors: Llinàs-Mallol Laura , Odette Chamoun Huacon Betty , Redondo Pachon Dolores , Padilla Eduardo , Arias-Cabrales Carlos , Burballa Carla , Iriarte-Abril Miren , Farrera-Núñez Júlia , Solà Eulàlia , José Pérez-Saéz María , Crespo Marta 
Published: May 2022

Abstract

BACKGROUND AND AIMS
COVID-19 infection has heavily impacted our national health system since March-2020. Although the kidney transplant (KT) activity was strongly reduced initially, nowadays it is partially recovered by using ‘COVID-clean’ pathways and vaccination of KT candidates since February-2021. However, scarce information is available regarding how de novo KT immunosuppression influences the serological status of vaccinated recipients.

METHOD
We reviewed the course of 38 de novo KT recipients transplanted between March-September 2021 fully vaccinated before KT. SARS-CoV-2 IgG antibodies against Spike (IgG-S) before and after KT (median: 32 days) were quantified with a serological assay (positive ≥13.0 AU/mL).

RESULTS
Of 38 recipients, 35 showed positive IgG-S at KT (92%). We exclude from the analysis, 4 recipients with COVID infection which interfered the analysis and 5 with inappropriate samples. The remaining 26 recipients had received the second dose of the mRNA vaccine a median time of 48 days before the pre-KT IgG determination. All patients maintained IgG-S over the cut-off after KT, but we observed that half de novo recipients (53.8%) showed a 50% reduction in the level of IgG-S at 1 month: 12/20 (60%) of those who received induction with basiliximab and 2/6 (33%) who received thymoglobulin. Regarding the impact of maintenance immunosuppression under induction with basiliximab, the IgG-S levels halved in 50% of those with tacrolimus-mycophenolate and 67% with tacrolimus-everolimus.
The restricted analysis of IgG-S levels excluding five outliers before KT (&gt;800 AU/mL) showed the most intense reduction in three KT recipients who received thymoglobulin-tacrolimus- mycophenolate (263.8 versus 68.8, 74%) compared with seven basiliximab-tacrolimus-mycophenolate cases (494.4 versus 359.8, 27%) and eleven basiliximab-tacrolimus-everolimus (344.0 versus 306.4, 11%) KT recipients.

CONCLUSION
Immunosuppression in de novo KT recipients reduces significantly the seroprotective levels of antibodies anti-Spike induced by COVID m-RNA vaccines in more than half the recipients. In our experience, the combination of thymoglobulin, tacrolimus and mycophenolate produces a more intense reduction than the combination of basiliximab with tacrolimus and mycophenolate or everolimus.