Arteriovenous fistula as the vascular access contributes to better survival of hemodialysis patients with COVID-19 infection.

BACKGROUND: While COVID-19 in chronic hemodialysis patients has high mortality and the pandemic will not end in the near future, effective follow up strategies should be implemented for these patients. Surgeries have been triaged according to their level of urgencies and arteriovenous fistula (AVF) operations were among elective surgeries. This study aimed to analyze the effect of vascular access on the outcomes of hemodialysis patients who had COVID-19. METHODS: One hundred four hemodialysis patients who had COVID-19 were retrospectively analyzed. Seventy-two of them had AVF as the vascular access while 32 of them had tunneled catheters. Inflammatory markers and outcomes of patients with AVFs and catheters were compared. A logistic regression analysis was performed in order to define factors that contribute to better outcomes in hemodialysis patients. RESULTS: COVID-19 had high mortality rate in hemodialysis patients (36.5%). Patients with catheters have higher peak ferritin levels (p = 0.02) and longer hospital stay (p = 0.00). Having AVF as the vascular access (OR = 3.36; 95% CI: 1.05-10.72; p = 0.041) and using medium cut-off dialyzers (OR = 7.99; 95% CI: 1.53-41.65; p = 0.014) were related to higher survival of the patients. COVID severity was inversely proportional to the survival (p = 0.000). CONCLUSIONS: AVFs contribute to higher survival of hemodialysis patients with COVID-19. Even in the pandemic era, end stage renal disease patients should be given the opportunity to have their vascular access properly created.

Waning of SARS-CoV-2 Vaccine-Induced Immune Response over 6 Months in Peritoneal Dialysis Patients and the Role of a Booster Dose in Maintaining Seropositivity.

INTRODUCTION: Although lower than general population, newly developed SARS-CoV-2 vaccines generate immune responses in end-stage kidney disease patients. However, the persistence of immune responses in the long term is not known yet. This study aimed to evaluate humoral immune responses in peritoneal dialysis (PD) patients over 6 months and to analyze the effects of the booster dose. METHODS: Humoral immune responses of PD patients were measured after initial SARS-CoV-2 vaccinations and after 6 months following initial vaccinations. Immune responses were compared between patients who received and did not receive booster doses. PD patients were compared with 41 hemodialysis (HD) patients and 61 healthy controls. Humoral immune responses were measured by a commercial test that detects antibodies toward the receptor-binding domain of the spike protein of SARS-CoV-2. RESULTS: Twenty PD patients were evaluated over 6 months. The initial seropositivity rate was 90.9% with inactivated vaccine and 100% with mRNA vaccine. Seropositivity decreased to 44.4% after 6 months, and a booster dose helped in maintaining the 100% of seropositivity (p = 0.005). Magnitude of humoral response at the 6th month was also higher in patients who received the third dose (1,132.8 ± 769.6 AU/mL vs. 400.0 ± 294.6 AU/mL; p = 0.015). Among patients who did not receive the third dose, those who got mRNA vaccine could maintain higher seropositivity than others who got inactivated vaccine (75% vs. 40% for PD, 81.8% vs. 50% for HD). Seropositivity and antibody levels were similar for PD and HD patients after 6 months (p = 0.24 and 0.56) but lower than healthy controls (p = 0.0013). CONCLUSION: SARS-CoV-2 vaccine-induced antibody levels and seropositivity of PD patients significantly fall after 6 months. A booster dose after around 3 months following initial immunization might help in maintaining seropositivity.

COVID-19 in Kidney Transplant Recipients: A Multicenter Experience from the First Two Waves of Pandemic.

BACKGROUND: Kidney transplant recipients have an increased risk of complications from COVID-19. However, data on the risk of allograft damage or death in kidney transplant recipients recovering from COVID-19 is limited. In addition, the first and second waves of the pandemic occurred at different times all over the world. In Turkey, the Health Minister confirmed the first case in March 2020; after that, the first wave occurred between March and August 2020; afterward, the second wave began in September 2020. This study aims to demonstrate the clinical presentations of kidney transplant recipients in the first two waves of the pandemic in Turkey and explore the impact of COVID-19 on clinical outcomes after the initial episode. METHODS: Patients with COVID-19 from seven centers were included in this retrospective cohort study. Initially, four hundred and eighty-eight kidney transplant recipients diagnosed with COVID-19 between 1 March 2020 to 28 February 2021 were enrolled. The endpoints were the occurrence of all-cause mortality, acute kidney injury, cytokine storm, and acute respiratory distress syndrome. In addition, longer-term outcomes such as mortality, need for dialysis, and allograft function of the surviving patients was analyzed. RESULTS: Four hundred seventy-five patients were followed up for a median of 132 days after COVID-19. Forty-seven patients (9.9%) died after a median length of hospitalization of 15 days. Although the mortality rate (10.1% vs. 9.8%) and intensive care unit admission (14.5% vs. 14.5%) were similar in the first two waves, hospitalization (68.8% vs. 29.7%; p < 0.001), acute kidney injury (44.2% vs. 31.8%; p = 0.009), acute respiratory distress syndrome (18.8% vs. 16%; p = 0.456), and cytokine storm rate (15.9% vs. 10.1%; p = 0.072) were higher in first wave compared to the second wave. These 47 patients died within the first month of COVID-19. Six (1.4%) of the surviving patients lost allografts during treatment. There was no difference in the median serum creatinine clearance of the surviving patients at baseline (52 mL/min [IQR, 47-66]), first- (56 mL/min [IQR, 51-68]), third- (51 mL/min [IQR,48-67]) and sixth-months (52 mL/min [IQR, 48-81]). Development of cytokine storm and posttransplant diabetes mellitus were independent predictors for mortality. CONCLUSIONS: Mortality remains a problem in COVID-19. All the deaths occur in the first month of COVID-19. Also, acute kidney injury is common in hospitalized patients, and some of the patients suffer from graft loss after the initial episode.

Antibody responses to inactivated SARS-CoV-2 vaccine in peritoneal dialysis patients.

INTRODUCTION: As end-stage renal disease (ESRD) patients generally have reduced responses to the vaccines, effectiveness of newly developed SARS-CoV-2 vaccines in ESRD are also matters of curiosity. We aimed to investigate the humoral responses of our peritoneal dialysis (PD) patients to the inactivated SARS-CoV-2 vaccine. METHODS: Humoral immune responses of 23 PD patients who received two doses of the inactivated SARS-CoV-2 vaccine were investigated with a commercial test that measures IgG antibodies towards receptor binding domain of SARS-CoV-2 spike protein. Seropositivity rates, antibody titers, and ESRD related clinical data were compared with 51 hemodialysis (HD) patients and 29 healthy volunteers. RESULTS: Seropositivity of PD patients with the inactivated vaccine was 95.6%. Both the rate of seropositivity and SARS-CoV-2 IgG antibody levels in PD patients were not different from the healthy controls (p = 0.85 and 0.19, respectively). While seropositivity rates were not different for PD or HD patients (p = 0.09), the magnitude of humoral responses was significantly higher in PD patients (p = 0.0001). There were no vaccine-related serious adverse events. In the 3-months clinical follow-up, none of the patients experienced SARS-CoV-2 infection. CONCLUSION: Two doses of the inactivated vaccine generate adequate humoral immune response in PD patients without any serious adverse events.

Antibody responses to the SARS-CoV-2 vaccines in hemodialysis patients: Is inactivated vaccine effective?

INTRODUCTION: Vaccines generally have reduced effectiveness in hemodialysis patients and a similar condition may also apply for the SARS-CoV-2 vaccines. The aim of this study was to analyze humoral responses of hemodialysis patients to SARS-CoV-2 vaccines. METHODS: Eighty-five maintenance hemodialysis patients who received either inactivated or mRNA SARS-CoV-2 vaccines were investigated. Antibody levels were measured by a commercial antibody kit, which detected antibodies toward receptor binding domain of the SARS-CoV-2 spike protein. Comparative analyzes were carried between vaccine groups and with a control group of 103 healthy volunteers. RESULTS: Seropositivity rate and antibody levels were significantly lower in hemodialysis patients who received inactivated vaccine (p = 0.000). While mRNA vaccine had better immunogenicity, both vaccines protected from symptomatic infection when seropositivity was achieved. DISCUSSION/CONCLUSION: When used in the same dose with the general population, inactivated SARS-CoV-2 vaccines generate reduced humoral response in hemodialysis patients. mRNA vaccines have better immunogenicity in this group.

COVID-19 in chronic kidney disease: a retrospective, propensity score-matched cohort study.

BACKGROUND: The prognostic factors for COVID-19 in patients with chronic kidney disease (CKD) are uncertain. We conducted a study to compare clinical and prognostic features between hospitalized COVID-19 patients with and without CKD. METHODS: Fifty-six patients with stage 3-5 CKD and propensity score-matched fifty-six patients without CKD were included in the study. Patients were followed-up at least fifteen days or until death after COVID-19 diagnosis. The endpoints were death from all causes, development of acute kidney injury (AKI) or cytokine release syndrome or respiratory failure, or admission to the intensive care unit (ICU). RESULTS: All patients were reviewed retrospectively over a median follow-up of 44 days (IQR, 36-52) after diagnosis of COVID-19. Patients with CKD had higher intensive care unit admission and mortality rates than the patients without CKD, but these results did not reach statistical significance (16 vs. 19; p = 0.54 and 11 vs. 16, p = 0.269, respectively). The frequency of AKI development was significantly higher in predialysis patients with CKD compared to the other group (8 vs. 5; p < 0.001), but there was no significant difference between the groups in terms of cytokine release syndrome (13 vs. 8; p = 0.226), follow-up in the ICU (19 vs. 16; p = 0.541), and respiratory failure (25 vs. 22, p = 0.566). Multivariate logistic regression analysis revealed that respiratory failure and AKI were independent risk factors for mortality. CONCLUSION: The mortality rates of COVID-19 patients with CKD had higher than COVID-19 patients without CKD. Also, AKI and respiratory failure were independently related to mortality.

Medium Cut-Off Dialysis Membranes: Can They Have Impact on Outcome of COVID-19 Hemodialysis Patients?

INTRODUCTION: Severe acute respiratory syndrome coronavirus-2 may lead to high levels of expression of inflammatory cytokines. Medium cut-off (MCO) membranes may make greater clearances for large-middle molecules (including cytokines) than low-flux (LF) membranes. In this study, we aimed to evaluate the impact of MCO membranes on outcome of COVID-19 patients on hemodialysis (HD). METHODS: Sixty COVID-19 HD patients were included in this study. The patients were categorized into 2 groups regarding type of HD membranes. Clinical data were taken from medical records. RESULTS: Initial crp and ferritin levels, which are surragates of cytokine storm and severity of disease in COVID-19, were significantly higher in MCO membrane group compared to LF group (p = 0.037 and 0.000, respectively). Although there were more patients with severe disease in MCO group, there were no significant differences regarding need for intensive care unit and death. CONCLUSION: It may be an option to use MCO membranes in HD patients with COVID-19 in order to reduce cytokine levels and prevent cytokine storm.

Evaluation of the relationship between COVID-19 pneumonia severity and pulmonary artery diameter measurement.

The goal of the present work was to examine associations between COVID-19 pneumonia severity and pulmonary artery diameter. A total of 101 patients with COVID-19 were included in this retrospective observational study. The patients were divided into three groups based on the CT images: 41 patients with mild pneumonia, group 2 had 39 patients with moderate pneumonia, and group 3 had 21 patients with severe pneumonia. Furthermore, the diameter of the main pulmonary artery was calculated as well as ascending aorta, right and left pulmonary artery diameters. Laboratory analysis results were also compared. Analyses show an increased main pulmonary artery diameter is associated with poorer prognosis for patients with COVID-19 pneumonia. Further studies are needed into the mechanisms between severe hypoxemia, increased inflammation, and vascular resistance and higher numbers of thromboembolic events.

COVID-19 in kidney transplant recipients: A multicenter experience in Istanbul.

INTRODUCTION: Management of COVID-19 in kidney transplant recipients should include treatment of the infection, regulation of immunosuppression, and supportive therapy. However, there is no consensus on this issue yet. This study aimed to our experiences with kidney transplant recipients diagnosed with COVID-19. MATERIAL AND METHODS: Kidney transplant recipients diagnosed with COVID-19 from five major transplant centers in Istanbul, Turkey, were included in this retrospective cohort study. Patients were classified as having moderate or severe pneumonia for the analysis. The primary endpoint was all-cause mortality. The secondary endpoints were acute kidney injury, the average length of hospital stay, admission to intensive care, and mechanical ventilation. RESULTS: Forty patients were reviewed retrospectively over a follow-up period of 32 days after being diagnosed with COVID-19. Cough, fever, and dyspnea were the most frequent symptoms in all patients. The frequency of previous induction and rejection therapy was significantly higher in the group with severe pneumonia compared to the moderate pneumonia group. None of the patients using cyclosporine A developed severe pneumonia. Five patients died during follow-up in the intensive care unit. None of the patients developed graft loss during follow-up. DISCUSSION: COVID-19 has been seen to more commonly cause moderate or severe pneumonia in kidney transplant recipients. Immunosuppression should be carefully reduced in these patients. Induction therapy with lymphocyte-depleting agents should be carefully avoided in kidney transplant recipients during the pandemic period.