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.

Characteristics and Survival Results of Peritoneal Dialysis Patients Suffering from COVID-19 in Turkey: A Multicenter National Study.

INTRODUCTION: We aimed to study the characteristics of peritoneal dialysis (PD) patients with coronavirus disease-19 (COVID-19), determine the short-term mortality and other medical complications, and delineate the factors associated with COVID-19 outcome. METHODS: In this multicenter national study, we included PD patients with confirmed COVID-19 from 27 centers. The baseline demographic, clinical, laboratory, and radiological data and outcomes at the end of the first month were recorded. RESULTS: We enrolled 142 COVID-19 patients (median age: 52 years). 58.2% of patients had mild disease at diagnosis. Lung involvement was detected in 60.8% of patients. Eighty-three (58.4%) patients were hospitalized, 31 (21.8%) patients were admitted to intensive care unit and 24 needed mechanical ventilation. Fifteen (10.5%) patients were switched to hemodialysis and hemodiafiltration was performed for four (2.8%) patients. Persisting pulmonary symptoms (n = 27), lower respiratory system infection (n = 12), rehospitalization for any reason (n = 24), malnutrition (n = 6), hypervolemia (n = 13), peritonitis (n = 7), ultrafiltration failure (n = 7), and in PD modality change (n = 8) were reported in survivors. Twenty-six patients (18.31%) died in the first month of diagnosis. The non-survivor group was older, comorbidities were more prevalent. Fever, dyspnea, cough, serious-vital disease at presentation, bilateral pulmonary involvement, and pleural effusion were more frequent among non-survivors. Age (OR: 1.102; 95% CI: 1.032-1.117; p: 0.004), moderate-severe clinical disease at presentation (OR: 26.825; 95% CI: 4.578-157.172; p < 0.001), and baseline CRP (OR: 1.008; 95% CI; 1,000-1.016; p: 0.040) were associated with first-month mortality in multivariate analysis. DISCUSSION/CONCLUSIONS: Early mortality rate and medical complications are quite high in PD patients with COVID-19. Age, clinical severity of COVID-19, and baseline CRP level are the independent parameters associated with mortality.

The Longitudinal Evolution of Post-COVID-19 Outcomes Among Hemodialysis Patients in Turkey.

Introduction: Hemodialysis (HD) patients have increased risk for short-term adverse outcomes of COVID-19. However, complications and survival at the post-COVID-19 period have not been published extensively. Methods: We conducted a national, multicenter observational study that included adult maintenance HD patients recovered from confirmed COVID-19. A control HD group without COVID-19 was selected from patients in the same center. We investigated the characteristics and outcomes in the follow-up of HD patients and compare them with the non-COVID-19 group. Results: A total of 1223 patients (635 patients in COVID-19 group, 588 patients in non-COVID-19 group) from 47 centers were included in the study. The patients' baseline and HD characteristics were almost similar. The 28th-day mortality and mortality between 28th day and 90th day were higher in the COVID-19 group than non-COVID-19 group (19 [3.0%] patients vs. none [0%]; 15 [2.4%] patients vs. 4 [0.7%] patients, respectively). The presence of respiratory symptoms, rehospitalization, need for home oxygen therapy, lower respiratory tract infection, and arteriovenous (AV) fistula thrombosis was significantly higher in the COVID-19 group in both the first 28 days and between 28 and 90 days. In the multivariable analysis, age (odds ratio [OR] [95% CI]: 1.029 [1.004-1.056]), group (COVID-19 group vs. non-COVID-19 group) (OR [95% CI]: 7.258 [2.538-20.751]), and vascular access type (tunneled catheter/AV fistula) (OR [95% CI]: 2.512 [1.249-5.051]) were found as independent parameters related to 90-day mortality. Conclusion: In the post-COVID-19 period, maintenance HD patients who have had COVID-19 have increased rehospitalization, respiratory problems, vascular access problems, and high mortality compared with the non-COVID-19 HD patients.

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.

Fluctuations in Interleukin-6 Levels during Hemodialysis Sessions with Medium Cutoff Membranes: An Analysis on COVID-19 Case Series.

INTRODUCTION: Interleukin-6 (IL-6) is one of the most important mediators of inflammation. It is also the culprit for a severe disease course in COVID-19. While COVID-19 has higher mortality in hemodialysis (HD) patients, medium cutoff (MCO) membranes were previously suggested as promising tools for better patient outcomes by purging inflammatory mediators. The aim of this study was to analyze changes in IL-6 levels of HD patients who were dialyzed via MCO membranes during their COVID-19 treatments. METHODS: This is an observational study on a group of HD patients who were admitted with COVID-19 diagnosis in a university hospital and intermittently dialyzed using MCO membranes during their hospital stay. IL-6 levels of the patients were measured before and after consecutive dialysis sessions by a commercial kit. Measurements were interpreted together with the clinical data. RESULTS: Nine patients with a total of 54 measurements were evaluated. IL-6 levels were significantly higher in patients who died (median and interquartile ranges [IQRs] of IL-6 levels for patients who died and survived were 112.0 pg/mL [48.3-399.4] and 5.3 pg/mL [2.2-27.4], respectively; p < 0.001). In the comparison of changes in IL-6 levels with dialysis sessions, patients who survived had lower post-dialysis levels (median: 4.5 pg/mL; IQR: 2.2-7.6). However, IL-6 levels had a tendency to increase with dialysis sessions in patients who could not survive COVID-19 (median: 237.0 pg/mL; IQR: 53.8-418.2). CONCLUSION: This study describes over time variations in IL-6 levels of COVID-19 patients undergoing HD with MCO membranes. The trend for the changes of IL-6 levels during dialysis sessions was not uniform for all patients. Surviving patients had decreasing levels of IL-6 with consecutive dialysis sessions, while nonsurvivors had an increasing trend.

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.

Impact of hospital-acquired acute kidney injury on Covid-19 outcomes in patients with and without chronic kidney disease: a multicenter retrospective cohort study

Background/aim: Hospital-acquired acute kidney injury (HA-AKI) may commonly develop in Covid-19 patients and is expected to have higher mortality. There is little comparative data investigating the effect of HA-AKI on mortality of chronic kidney disease (CKD) patients and a control group of general population suffering from Covid-19. Materials and methods: HA-AKI development was assessed in a group of stage 3­5 CKD patients and control group without CKD among adult patients hospitalized for Covid-19. The role of AKI development on the outcome (in-hospital mortality and admission to the intensive care unit [ICU]) of patients with and without CKD was compared. Results: Among 621 hospitalized patients (age 60 [IQR: 47­73]), women: 44.1%), AKI developed in 32.5% of the patients, as stage 1 in 84.2%, stage 2 in 8.4%, and stage 3 in 7.4%. AKI developed in 48.0 % of CKD patients, whereas it developed in 17.6% of patients without CKD. CKD patients with HA-AKI had the highest mortality rate of 41.1% compared to 14.3% of patients with HA-AKI but no CKD (p < 0.001). However, patients with AKI+non-CKD had similar rates of ICU admission, mechanical ventilation, and death rate to patients with CKD without AKI. Adjusted mortality risks of the AKI+non-CKD group (HR: 9.0, 95% CI: 1.9­44.2) and AKI+CKD group (HR: 7.9, 95% CI: 1.9­33.3) were significantly higher than that of the non-AKI+non-CKD group. Conclusion: AKI frequently develops in hospitalized patients due to Covid-19 and is associated with high mortality. HA-AKI has worse outcomes whether it develops in patients with or without CKD, but the worst outcome was seen in AKI+CKD patients.

Characteristics and outcomes of hospitalised older patients with chronic kidney disease and COVID-19: A multicenter nationwide controlled study.

OBJECTIVE: Older adults with co-morbidities have been reported to be at higher risk for adverse outcomes of coronavirus disease 2019 (COVID-19). The characteristics of COVID-19 in older patients and its clinical outcomes in different kidney disease groups are not well known. METHODS: Data were retrieved from a national multicentric database supported by Turkish Society of Nephrology, which consists of retrospectively collected data between 17 April 2020 and 31 December 2020. Hospitalised patients aged 18 years or older with confirmed COVID-19 diagnosis suffering from stage 3-5 chronic kidney disease (CKD) or on maintenance haemodialysis (HD) treatment were included in the database. Non-uraemic hospitalised patients with COVID-19 were also included as the control group. RESULTS: We included 879 patients [388 (44.1%) female, median age: 63 (IQR: 50-73) years]. The percentage of older patients in the CKD group was 68.8% (n = 188/273), in the HD group was 49.0% (n = 150/306) and in the control group was 30.4% (n = 70/300). Co-morbidities were higher in the CKD and HD groups. The rate of presentation with severe-critical disease was higher in the older CKD and HD groups (43.6%, 55.3% and 16.1%, respectively). Among older patients, the intensive care unit (ICU) admission rate was significantly higher in the CKD and HD groups than in the control group (38.8%, 37.3% and 15.7%, respectively). In-hospital mortality or death and/or ICU admission rates in the older group were significantly higher in the CKD (29.3% and 39.4%) and HD groups (26.7% and 30.1%) compared with the control group (8.6% and 17.1%). In the multivariate analysis, in-hospital mortality rates in CKD and HD groups were higher than control group [hazard ratio (HR): 4.33 (95% confidence interval [CI]: 1.53-12.26) and HR: 3.09 (95% CI: 1.04-9.17), respectively]. CONCLUSION: Among older COVID-19 patients, in-hospital mortality is significantly higher in those with stage 3-5 CKD and on maintenance HD than older patients without CKD regardless of demographic characteristics, co-morbidities, clinical and laboratory data on admission.

Predicting the outcome of COVID-19 infection in kidney transplant recipients.

BACKGROUND: We aimed to present the demographic characteristics, clinical presentation, and outcomes of our multicenter cohort of adult KTx recipients with COVID-19. METHODS: We conducted a multicenter, retrospective study using data of patients hospitalized for COVID-19 collected from 34 centers in Turkey. Demographic characteristics, clinical findings, laboratory parameters (hemogram, CRP, AST, ALT, LDH, and ferritin) at admission and follow-up, and treatment strategies were reviewed. Predictors of poor clinical outcomes were analyzed. The primary outcomes were in-hospital mortality and the need for ICU admission. The secondary outcome was composite in-hospital mortality and/or ICU admission. RESULTS: One hundred nine patients (male/female: 63/46, mean age: 48.4 ± 12.4 years) were included in the study. Acute kidney injury (AKI) developed in 46 (42.2%) patients, and 4 (3.7%) of the patients required renal replacement therapy (RRT). A total of 22 (20.2%) patients were admitted in the ICU, and 19 (17.4%) patients required invasive mechanical ventilation. 14 (12.8%) of the patients died. Patients who were admitted in the ICU were significantly older (age over 60 years) (38.1% vs 14.9%, p = 0.016). 23 (21.1%) patients reached to composite outcome and these patients were significantly older (age over 60 years) (39.1% vs. 13.9%; p = 0.004), and had lower serum albumin (3.4 g/dl [2.9-3.8] vs. 3.8 g/dl [3.5-4.1], p = 0.002), higher serum ferritin (679 µg/L [184-2260] vs. 331 µg/L [128-839], p = 0.048), and lower lymphocyte counts (700/µl [460-950] vs. 860 /µl [545-1385], p = 0.018). Multivariable analysis identified presence of ischemic heart disease and initial serum creatinine levels as independent risk factors for mortality, whereas age over 60 years and initial serum creatinine levels were independently associated with ICU admission. On analysis for predicting secondary outcome, age above 60 and initial lymphocyte count were found to be independent variables in multivariable analysis. CONCLUSION: Over the age of 60, ischemic heart disease, lymphopenia, poor graft function were independent risk factors for severe COVID-19 in this patient group. Whereas presence of ischemic heart disease and poor graft function were independently associated with mortality.

Determinants of mortality in a large group of hemodialysis patients hospitalized for COVID-19.

BACKGROUND: Maintenance hemodialysis (MHD) patients are at increased risk for coronavirus disease 2019 (COVID-19). The aim of this study was to describe clinical, laboratory, and radiologic characteristics and determinants of mortality in a large group of MHD patients hospitalized for COVID-19. METHODS: This multicenter, retrospective, observational study collected data from 47 nephrology clinics in Turkey. Baseline clinical, laboratory and radiological characteristics, and COVID-19 treatments during hospitalization, need for intensive care and mechanical ventilation were recorded. The main study outcome was in-hospital mortality and the determinants were analyzed by Cox regression survival analysis. RESULTS: Of 567 MHD patients, 93 (16.3%) patients died, 134 (23.6%) patients admitted to intensive care unit (ICU) and 91 of the ones in ICU (67.9%) needed mechanical ventilation. Patients who died were older (median age, 66 [57-74] vs. 63 [52-71] years, p = 0.019), had more congestive heart failure (34.9% versus 20.7%, p = 0.004) and chronic obstructive pulmonary disease (23.6% versus 12.7%, p = 0.008) compared to the discharged patients. Most patients (89.6%) had radiological manifestations compatible with COVID-19 pulmonary involvement. Median platelet (166 × 103 per mm3 versus 192 × 103 per mm3, p = 0.011) and lymphocyte (800 per mm3 versus 1000 per mm3, p < 0.001) counts and albumin levels (median, 3.2 g/dl versus 3.5 g/dl, p = 0.001) on admission were lower in patients who died. Age (HR: 1.022 [95% CI, 1.003-1.041], p = 0.025), severe-critical disease clinical presentation at the time of diagnosis (HR: 6.223 [95% CI, 2.168-17.863], p < 0.001), presence of congestive heart failure (HR: 2.247 [95% CI, 1.228-4.111], p = 0.009), ferritin levels on admission (HR; 1.057 [95% CI, 1.006-1.111], p = 0.028), elevation of aspartate aminotransferase (AST) (HR; 3.909 [95% CI, 2.143-7.132], p < 0.001) and low platelet count (< 150 × 103 per mm3) during hospitalization (HR; 1.864 [95% CI, 1.025-3.390], p = 0.041) were risk factors for mortality. CONCLUSION: Hospitalized MHD patients with COVID-19 had a high mortality rate. Older age, presence of heart failure, clinical severity of the disease at presentation, ferritin level on admission, decrease in platelet count and increase in AST level during hospitalization may be used to predict the mortality risk of these patients.

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.

Mortality analysis of COVID-19 infection in chronic kidney disease, haemodialysis and renal transplant patients compared with patients without kidney disease: a nationwide analysis from Turkey.

BACKGROUND: Chronic kidney disease (CKD) and immunosuppression, such as in renal transplantation (RT), stand as one of the established potential risk factors for severe coronavirus disease 2019 (COVID-19). Case morbidity and mortality rates for any type of infection have always been much higher in CKD, haemodialysis (HD) and RT patients than in the general population. A large study comparing COVID-19 outcome in moderate to advanced CKD (Stages 3-5), HD and RT patients with a control group of patients is still lacking. METHODS: We conducted a multicentre, retrospective, observational study, involving hospitalized adult patients with COVID-19 from 47 centres in Turkey. Patients with CKD Stages 3-5, chronic HD and RT were compared with patients who had COVID-19 but no kidney disease. Demographics, comorbidities, medications, laboratory tests, COVID-19 treatments and outcome [in-hospital mortality and combined in-hospital outcome mortality or admission to the intensive care unit (ICU)] were compared. RESULTS: A total of 1210 patients were included [median age, 61 (quartile 1-quartile 3 48-71) years, female 551 (45.5%)] composed of four groups: control (n = 450), HD (n = 390), RT (n = 81) and CKD (n = 289). The ICU admission rate was 266/1210 (22.0%). A total of 172/1210 (14.2%) patients died. The ICU admission and in-hospital mortality rates in the CKD group [114/289 (39.4%); 95% confidence interval (CI) 33.9-45.2; and 82/289 (28.4%); 95% CI 23.9-34.5)] were significantly higher than the other groups: HD = 99/390 (25.4%; 95% CI 21.3-29.9; P < 0.001) and 63/390 (16.2%; 95% CI 13.0-20.4; P < 0.001); RT = 17/81 (21.0%; 95% CI 13.2-30.8; P = 0.002) and 9/81 (11.1%; 95% CI 5.7-19.5; P = 0.001); and control = 36/450 (8.0%; 95% CI 5.8-10.8; P < 0.001) and 18/450 (4%; 95% CI 2.5-6.2; P < 0.001). Adjusted mortality and adjusted combined outcomes in CKD group and HD groups were significantly higher than the control group [hazard ratio (HR) (95% CI) CKD: 2.88 (1.52-5.44); P = 0.001; 2.44 (1.35-4.40); P = 0.003; HD: 2.32 (1.21-4.46); P = 0.011; 2.25 (1.23-4.12); P = 0.008), respectively], but these were not significantly different in the RT from in the control group [HR (95% CI) 1.89 (0.76-4.72); P = 0.169; 1.87 (0.81-4.28); P = 0.138, respectively]. CONCLUSIONS: Hospitalized COVID-19 patients with CKDs, including Stages 3-5 CKD, HD and RT, have significantly higher mortality than patients without kidney disease. Stages 3-5 CKD patients have an in-hospital mortality rate as much as HD patients, which may be in part because of similar age and comorbidity burden. We were unable to assess if RT patients were or were not at increased risk for in-hospital mortality because of the relatively small sample size of the RT patients in this study.

Kidney function on admission predicts in-hospital mortality in COVID-19.

BACKGROUND: Recent data have suggested the presence of a reciprocal relationship between COVID-19 and kidney function. To date, most studies have focused on the effect of COVID-19 on kidney function, whereas data regarding kidney function on the COVID-19 prognosis is scarce. Therefore, in this study, we aimed to investigate the association between eGFR on admission and the mortality rate of COVID-19. METHODS: We recruited 336 adult consecutive patients (male: 57.1%, mean age: 55.0±16.0 years) that were hospitalized with the diagnosis of COVID-19 in a tertiary care university hospital. Data were collected from the electronic health records of the hospital. On admission, eGFR was calculated using the CKD-EPI formula. Acute kidney injury was defined according to the KDIGO criteria. Binary logistic regression and Cox regression analyses were used to assess the relationship between eGFR on admission and in-hospital mortality of COVID-19. RESULTS: Baseline eGFR was under 60 mL/min/1.73m2 in 61 patients (18.2%). Acute kidney injury occurred in 29.2% of the patients. In-hospital mortality rate was calculated as 12.8%. Age-adjusted and multivariate logistic regression analysis (p: 0.005, odds ratio: 0.974, CI: 0.956-0.992) showed that baseline eGFR was independently associated with mortality. Additionally, age-adjusted Cox regression analysis revealed a higher mortality rate in patients with an eGFR under 60 mL/min/1.73m2. CONCLUSIONS: On admission eGFR seems to be a prognostic marker for mortality in patients with COVID-19. We recommend that eGFR be measured in all patients on admission and used as an additional tool for risk stratification. Close follow-up should be warranted in patients with a reduced eGFR.