Outcome and effect of vaccination in SARS-CoV-2 Omicron infection in hemodialysis patients: a cohort study.

BACKGROUND: Hemodialysis patients are at high risk of Covid-19, though vaccination has significant efficacy in preventing and reducing the severity of infection. Little information is available on disease severity and vaccine efficacy since the dissemination of the Omicron variant. METHODS: In a multi-center study, during a period of the epidemic driven by the Omicron variant, all hemodialysis patients positive for SARS-CoV-2 were identified. Outcomes were analyzed according to predictor variables including vaccination status. Risk of infection was analyzed using a Cox proportional hazards model. RESULTS: SARS-CoV-2 infection was identified in 1126 patients including 200 (18%) unvaccinated, 56 (5%) post first dose, 433 (38%) post second dose, and 437 (39%) at least 7 days beyond their third dose. The majority of patients had a mild course but 160 (14%) were hospitalized and 28 (2%) died. In regression models adjusted for age and comorbidity, two-dose vaccination was associated with a 39% (95%CI: 2%-62%) reduction in admissions, but third doses provided additional protection, with a 51% (95%CI: 25%-69%) further reduction in admissions. Among 1265 patients at risk at the start of the observation period, SARS-CoV-2 infection was observed in 211 (17%). Two-dose vaccination was associated with a 41% (95%CI: 3%-64%) reduction in the incidence of infection, with no clear additional effect provided by third doses. CONCLUSIONS: These data demonstrate lower incidence of SARS-CoV-2 infection after vaccination in dialysis patients during an Omicron dominant period of the epidemic. Among those developing infection, severe illness was less common with prior vaccination, particularly after third vaccine doses.

Severity of COVID-19 after Vaccination among Hemodialysis Patients: An Observational Cohort Study.

BACKGROUND AND OBJECTIVES: Patients receiving hemodialysis are at high risk from coronavirus disease 2019 (COVID-19) and demonstrate impaired immune responses to vaccines. There have been several descriptions of their immunologic responses to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccination, but few studies have described the clinical efficacy of vaccination in patients on hemodialysis. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: In a multicenter observational study of the London hemodialysis population undergoing surveillance PCR testing during the period of vaccine rollout with BNT162b2 and AZD1222, all of those positive for SARS-CoV-2 were identified. Clinical outcomes were analyzed according to predictor variables, including vaccination status, using a mixed effects logistic regression model. Risk of infection was analyzed in a subgroup of the base population using a Cox proportional hazards model with vaccination status as a time-varying covariate. RESULTS: SARS-CoV-2 infection was identified in 1323 patients of different ethnicities (Asian/other, 30%; Black, 38%; and White, 32%), including 1047 (79%) unvaccinated, 86 (7%) after first-dose vaccination, and 190 (14%) after second-dose vaccination. The majority of patients had a mild course; however, 515 (39%) were hospitalized, and 172 (13%) died. Older age, diabetes, and immune suppression were associated with greater illness severity. In regression models adjusted for age, comorbidity, and time period, prior two-dose vaccination was associated with a 75% (95% confidence interval, 56 to 86) lower risk of admission and 88% (95% confidence interval, 70 to 95) fewer deaths compared with unvaccinated patients. No loss of protection was seen in patients over 65 years or with increasing time since vaccination, and no difference was seen between vaccine types. CONCLUSIONS: These data demonstrate a substantially lower risk of severe COVID-19 after vaccination in patients on dialysis who become infected with SARS-CoV-2.

Point of care testing using rapid automated antigen testing for SARS-COV-2 in care homes – an exploratory safety, usability and diagnostic agreement evaluation

IntroductionSuccessful adoption of POCTs (Point-of-Care tests) for COVID-19 in care homes requires the identification of ideal use cases and a full understanding of the contextual and usability factors that affect test results and minimise biosafety risks. This paper presents a scoping-usability and test performance study of a microfluidic immunofluorescence assay for COVID-19 in care homes.MethodsA mixed-methods evaluation was conducted in four UK care homes to scope usability and to assess the agreement with qRT-PCR. A dry run with luminescent dye was conducted to explore biosafety issues.ResultsThe agreement analysis was conducted on 227 asymptomatic participants (159 staff and 68 residents) and 14 symptomatic participants (5 staff and 9 residents). Asymptomatic specimens showed 50% (95% CI:1.3%?98.7%) positive agreement and 96% (95% CI: 92.5%?98.1%) negative agreement with overall prevalence and bias-adjusted Kappa (PABAK) of 0.911 (95% CI: 0.857?0.965). Symptomatic specimens showed 83.3% (95% CI: 35.9%?99.6%) positive agreement and 100% (95% CI: 63.1%?100%) negative agreement with overall prevalence and bias-adjusted Kappa (PABAK) of 0.857 (95% CI: 0.549?1). The dry run highlighted four main sources of contamination that led to the modification of the standard operating procedures. Simulation post-modification showed no further evidence of contamination.ConclusionCareful consideration of biosafety issues and contextual factors associated with care home are mandatory for safe use the POCT. Whilst POCT may have some utility for ruling out COVID-19, further diagnostic accuracy evaluations are needed to promote effective adoption.

COVID-19-related acute kidney injury; incidence, risk factors and outcomes in a large UK cohort.

BACKGROUND: Acute kidney injury (AKI) is common among patients hospitalised with COVID-19 and associated with worse prognosis. The aim of this study was to investigate the epidemiology, risk factors and outcomes of AKI in patients with COVID-19 in a large UK tertiary centre. METHODS: We analysed data of consecutive adults admitted with a laboratory-confirmed diagnosis of COVID-19 across two sites of a hospital in London, UK, from 1st January to 13th May 2020. RESULTS: Of the 1248 inpatients included, 487 (39%) experienced AKI (51% stage 1, 13% stage 2, and 36% stage 3). The weekly AKI incidence rate gradually increased to peak at week 5 (3.12 cases/100 patient-days), before reducing to its nadir (0.83 cases/100 patient-days) at the end the study period (week 10). Among AKI survivors, 84.0% had recovered renal function to pre-admission levels before discharge and none required on-going renal replacement therapy (RRT). Pre-existing renal impairment [odds ratio (OR) 3.05, 95%CI 2.24-4,18; p <  0.0001], and inpatient diuretic use (OR 1.79, 95%CI 1.27-2.53; p <  0.005) were independently associated with a higher risk for AKI. AKI was a strong predictor of 30-day mortality with an increasing risk across AKI stages [adjusted hazard ratio (HR) 1.59 (95%CI 1.19-2.13) for stage 1; p < 0.005, 2.71(95%CI 1.82-4.05); p < 0.001for stage 2 and 2.99 (95%CI 2.17-4.11); p < 0.001for stage 3]. One third of AKI3 survivors (30.7%), had newly established renal impairment at 3 to 6 months. CONCLUSIONS: This large UK cohort demonstrated a high AKI incidence and was associated with increased mortality even at stage 1. Inpatient diuretic use was linked to a higher AKI risk. One third of survivors with AKI3 exhibited newly established renal impairment already at 3-6 months.

Risk of COVID-19 Disease, Dialysis Unit Attributes, and Infection Control Strategy among London In-Center Hemodialysis Patients.

BACKGROUND AND OBJECTIVES: Patients receiving in-center hemodialysis treatment face unique challenges during the coronavirus disease 2019 (COVID-19) pandemic, specifically the need to attend for treatment that prevents self-isolation. Dialysis unit attributes and isolation strategies that might reduce dialysis center COVID-19 infection rates have not been previously examined. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: We explored the role of variables, including community disease burden, dialysis unit attributes (size and layout), and infection control strategies, on rates of COVID-19 among patients receiving in-center hemodialysis in London, United Kingdom, between March 2, 2020 and May 31, 2020. The two outcomes were defined as (1) a positive test for infection or admission with suspected COVID-19 and (2) admission to the hospital with suspected infection. Associations were examined using a discrete time multilevel time-to-event analysis. RESULTS: Data on 5755 patients dialyzing in 51 units were analyzed; 990 (17%) tested positive and 465 (8%) were admitted with suspected COVID-19 between March 2 and May 31, 2020. Outcomes were associated with age, diabetes, local community COVID-19 rates, and dialysis unit size. A greater number of available side rooms and the introduction of mask policies for asymptomatic patients were inversely associated with outcomes. No association was seen with sex, ethnicity, or deprivation indices, nor with any of the different isolation strategies. CONCLUSIONS: Rates of COVID-19 in the in-center hemodialysis population relate to individual factors, underlying community transmission, unit size, and layout.

Is point-of-care testing feasible and safe in care homes in England? An exploratory usability and accuracy evaluation of a point-of-care polymerase chain reaction test for SARS-CoV-2.

INTRODUCTION: Reliable rapid testing for COVID-19 is needed in care homes to reduce the risk of outbreaks and enable timely care. This study aimed to examine the usability and test performance of a point of care polymerase chain reaction (PCR) test for detection of SARS-CoV-2 (POCKITTM Central) in care homes. METHODS: POCKITTM Central was evaluated in a purposeful sample of four UK care homes. Test agreement with laboratory real-time PCR and usability and used errors were assessed. RESULTS: No significant usability-related hazards emerged, and the sources of error identified were found to be amendable with minor changes in training or test workflow. POCKITTM Central has acceptable sensitivity and specificity based on RT-PCR as the reference standard, especially for symptomatic cases.Asymptomatic specimens showed 83.3% (95% confidence interval (CI): 35.9-99.6%) positive agreement and 98.7% negative agreement (95% CI: 96.2-99.7%), with overall prevalence and bias-adjusted kappa (PABAK) of 0.965 (95% CI: 0.932- 0.999). Symptomatic specimens showed 100% (95% CI: 2.5-100%) positive agreement and 100% negative agreement (95% CI: 85.8-100%), with overall PABAK of 1.Recommendations are provided to mitigate the frequency of occurrence of the residual use errors observed. Integration pathways were discussed to identify opportunities and limitations of adopting POCKIT™ Central for screening and diagnostic testing purposes. CONCLUSIONS: Point-of-care PCR testing in care homes can be considered with appropriate preparatory steps and safeguards. Further diagnostic accuracy evaluations and in-service evaluation studies should be conducted, if the test is to be implemented more widely, to build greater certainty on this initial exploratory analysis.

Acute Peritoneal Dialysis With Percutaneous Catheter Insertion for COVID-19-Associated Acute Kidney Injury in Intensive Care: Experience From a UK Tertiary Center.

INTRODUCTION: During the coronavirus disease 2019 (COVID-19) pandemic in 2020, high rates of acute kidney injury (AKI) in critically unwell patients are being reported, leading to an increased demand for renal replacement therapy (RRT). Providing RRT for this large number of patients is proving challenging, and so alternatives to continuous renal replacement therapies (CRRT) in the intensive care unit (ICU) are needed. Peritoneal dialysis (PD) can be initiated immediately after percutaneous insertion of the catheter, but there are concerns about impact on ventilation and RRT efficacy. We sought to describe our recent experience with percutaneous catheter insertion and peritoneal dialysis in patients in the ICU with COVID-19 infection. METHOD: Patients were selected according to local protocol, and catheters were inserted percutaneously by experienced operators using a Seldinger technique. Sequential Organ Failure Assessment (SOFA) score and ventilation requirements were recorded at the time of insertion and 24 hours later. Procedural complications, proportion of RRT provided by PD, renal recovery, and RRT parameters (serum potassium and maximum base excess) during PD were assessed. RESULTS: Percutaneous PD catheters were successfully inserted in 37 of 44 patients (84.1%) after a median of 13.5 days (interquartile range [IQR] = 10.0, 20.3 days) in the ICU. No adverse events were reported; SOFA scores and ventilation requirements were comparable before and after insertion; and adequate RRT parameters were achieved. The median proportion of RRT provided by PD following catheter insertion was 94.6% (IQR = 75.0, 100%). CONCLUSION: Peritoneal dialysis provides a safe and effective alternative to CRRT in selected patients with AKI and COVID-19 infection requiring ventilation on intensive care.

Provision of acute renal replacement therapy, using three separate modalities, in critically ill patients during the COVID-19 pandemic. An after action review from a UK tertiary critical care centre.

PURPOSE: The aim of this study is to describe the incidence of Acute Kidney Injury (AKI) amongst patients admitted to the Intensive Care Unit (ICU) with COVID-19. In addition we aim to detail the range of Renal Replacement Therapy (RRT) modalities offered to these patients (including peritoneal dialysis - PD - and intermittent haemodialysis - IHD) in order to meet demand during pandemic conditions. MATERIALS AND METHODS: Single-centre retrospective case note review of adult patients with confirmed COVID-19 admitted to ICU. RESULTS: Amongst 136 patients without a prior history of End Stage Kidney Disease (ESKD), 108 (79%) developed AKI and 63% of admitted patients received RRT. Due to resource limitations the range of RRT options were expanded from solely Continuous Veno-Venous HaemoDiaFiltration (CVVHDF - our usual standard of care) to include PD (in 35 patients) and IHD (in 15 patients). During the study period the proportion of RRT provided within ICU as CVVHDF fell from 100% to a nadir of 39%. There were no significant complications of either PD or IHD. CONCLUSIONS: During periods of resource limitations PD and IHD can safely be used to reduce dependence on CVVHDF in select patients with AKI secondary to COVID-19.