Peritoneal dialysis-associated peritonitis presenting with Ralstonia pickettii infection: A novel series of three cases during the COVID-19 pandemic.

Peritoneal dialysis (PD)-associated peritonitis secondary to Ralstonia infection is very rare. Ralstonia pickettii is an organism that can grow in contaminated saline, water, chlorhexidine, and other medical products used in laboratories and the clinical setting. Infective endocarditis, prosthetic joint, and severe chest infections are previously reported with R. pickettii infection. We report a novel series of three cases diagnosed with PD-associated peritonitis caused by R. pickettii, where the cases appeared consecutively to our unit during a span of 4 weeks. During the COVID-19 pandemic, there were increased uses of non-sterile gloves by clinical staff as a form of personal protective equipment throughout patient interaction and PD exchange, as recommended by local hospital policy for all staff attending to patient care. A multidisciplinary team root cause analysis of our cases suggested non-sterile gloves being the likely source of environmental contamination, leading to PD-associated peritonitis caused by R. pickettii in this scenario.

Investigating Longer Term Antibody Response Following Covid-19 Vaccination in Patients Receiving Peritoneal Dialysis—a Single-Center Observational Study

BACKGROUND AND AIMS Individuals with end-stage kidney disease (ESKD) have a greater susceptibility towards coronavirus disease 2019 (COVID-19) infection compared to those without chronic kidney disease or ESKD, and these patients are more vulnerable to poor clinical outcomes. The introduction of COVID-19 vaccination programs displayed efficacy to improving clinical outcomes. A study based in the UK reported excellent humoral responses to the Pfizer BNT162b2 vaccine, but suboptimal responses to the Oxford AstraZeneca ChAdOx1-nCoV-19(AZD1222) vaccine amongst hemodialysis patients. High rate of humoral responses to two doses of the COVID-19 vaccination has been reported within small cohorts of peritoneal dialysis (PD) patients 3 to 8 weeks post vaccination, whilst one study confirmed maintenance of significant humoral responses 6 months post vaccination with the Pfizer BNT162b2 vaccine. Our study aimed at evaluating longer-term antibody responses—6 months after a two-dose regimen of the Pfizer BNT162b2 and Oxford AstraZeneca ChAdOx1-nCoV-19 (AZD1222) vaccines in patients receiving PD. METHOD This is a single-center observational study conducted for PD patients who were offered both doses of the COVID-19 vaccine [either Pfizer BNT162b2 or Oxford AstraZeneca ChAdOx1-nCoV-19(AZD1222)] since universal introduction of the vaccination program in our local area in December 2020. COVID-19 antibody testing was performed using the Siemens’ immunoassay targeting the spike protein S1 RBD (an index ≥ 1.0 was deemed as a positive result) between October and November 2021. Demographic and baseline clinical data were collected for each patient, and analysis focused on comparing the characteristics between PD patients with positive and negative COVID-19 antibody statuses. Statistical analysis was performed using SPSS version 24. RESULTS Eighty-six patients were included in this study. The median age was 62 years (47–71) with a predominance of males (61.6%) and Caucasian ethnicity (75.6%). The majority of patients have hypertension (84.8%) with 38% having a history of cardiovascular disease and 34% being diabetic. Ten patients (11.6%) previously received a kidney transplant with 7 patients (8.2%) currently on immunosuppressive treatment, and 15 patients (17.4%) previously receiving such treatments. A total of 81 patients received both doses of the COVID-19 vaccine, of which 57 (70.4%) received Pfizer BNT162b2, 16 (19.7%) received Oxford AstraZeneca ChAdOx1-nCoV-19 (AZD1222) and the type of vaccine was unknown in 8 patients (9.9%). A total of 72 patients were COVID-19 antibody tested between October and November 2021 in which 68 (94.4%) had a positive antibody and 4 (5.6%) had a negative antibody test. The median time between first dose of the COVID-19 vaccination and antibody testing was 9 (8.6–9.5) months and the median time between second dose of the COVID-19 vaccination and antibody testing was 6.3 (5.8–6.7) months. Comparing the demographic and clinical characteristics between patients with positive and negative antibodies, a higher proportion of patients with history of receiving immunosuppression (currently or previously;P = 0.004) had a negative antibody status despite receiving two doses of COVID-19 vaccination. There were no further significant differences observed. Full study results are presented in Tables 1 and 2. CONCLUSION In our cohort of PD patients, detectable humoral response to COVID-19 vaccination was sustained 6 months following vaccination irrespective of the type of vaccination received. A higher proportion of patients with a history of receiving immunosuppression (current or past) had a poor antibody response following COVID-19 vaccinations, highlighting the importance of considering focused COVID-19 vaccination strategies in the context of immunosuppression.

Evaluating the antibody response to SARS-COV-2 vaccination amongst kidney transplant recipients at a single nephrology centre.

BACKGROUND AND OBJECTIVES: Kidney transplant recipients are highly vulnerable to the serious complications of severe acute respiratory syndrome coronavirus 2 (SARS-COV-2) infections and thus stand to benefit from vaccination. Therefore, it is necessary to establish the effectiveness of available vaccines as this group of patients was not represented in the randomized trials. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: A total of 707 consecutive adult kidney transplant recipients in a single center in the United Kingdom were evaluated. 373 were confirmed to have received two doses of either the BNT162b2 (Pfizer-BioNTech) or AZD1222 (Oxford-AstraZeneca) and subsequently had SARS-COV-2 antibody testing were included in the final analysis. Participants were excluded from the analysis if they had a previous history of SARS-COV-2 infection or were seropositive for SARS-COV-2 antibody pre-vaccination. Multivariate and propensity score analyses were performed to identify the predictors of antibody response to SARS-COV-2 vaccines. The primary outcome was seroconversion rates following two vaccine doses. RESULTS: Antibody responders were 56.8% (212/373) and non-responders 43.2% (161/373). Antibody response was associated with greater estimated glomerular filtration (eGFR) rate [odds ratio (OR), for every 10 ml/min/1.73m2 = 1.40 (1.19-1.66), P<0.001] whereas, non-response was associated with mycophenolic acid immunosuppression [OR, 0.02(0.01-0.11), p<0.001] and increasing age [OR per 10year increase, 0.61(0.48-0.78), p<0.001]. In the propensity-score analysis of four treatment variables (vaccine type, mycophenolic acid, corticosteroid, and triple immunosuppression), only mycophenolic acid was significantly associated with vaccine response [adjusted OR by PSA 0.17 (0.07-0.41): p<0.001]. 22 SARS-COV-2 infections were recorded in our cohort following vaccination. 17(77%) infections, with 3 deaths, occurred in the non-responder group. No death occurred in the responder group. CONCLUSION: Vaccine response in allograft recipients after two doses of SARS-COV-2 vaccine is poor compared to the general population. Maintenance with mycophenolic acid appears to have the strongest negative impact on vaccine response.

Increasing Uptake of COVID-19 Vaccination and Reducing Health Inequalities in Patients on Renal Replacement Therapy-Experience from a Single Tertiary Centre.

BACKGROUND: COVID-19 vaccination has changed the landscape of the COVID-19 pandemic; however, decreased uptake due to vaccine hesitancy has been observed, particularly in patients from minority ethnic backgrounds and socially deprived areas. These patient characteristics are common in patients on Renal Replacement Therapy (RRT), a population at extremely high risk of developing serious illness from COVID-19 and who would thus benefit the most from the vaccination programme. We designed a bespoke COVID-19 vaccination programme for our RRT population with the aim of decreasing health inequalities and increasing vaccination uptake. METHODS: Key interventions included addressing vaccine hesitancy by deploying the respective clinical teams as trusted messengers, prompt eligible patient identification and notification, the deployment of resources to optimise vaccine administration in a manner convenient to patients, and the timely collection and analysis of local safety and efficacy data. First, COVID-19 vaccination data in relation to ethnicity and social deprivation in our RRT population, measured by the multiple deprivation index, were analysed and compared to uptake data in the total regional adult clinically extremely vulnerable (CEV) population in Greater Manchester (GM). Univariate logistic regression analysis was used to explore the factors associated with not receiving a vaccine. RESULTS: Out of 1156 RRT patients included in this analysis, 96.7% received the first dose of the vaccination compared to 93% in the cohort of CEV patients in the GM. Age, gender, ethnicity, and a lower index of multiple deprivation were not identified as significant risk factors for poor first dose vaccine uptake in our cohort. Vaccine uptake in Asian and Black RRT patients was 94.9% and 92.3%, respectively, compared to 93% and 76.2% for the same ethnic groups in the reference CEV GM. Vaccine uptake was 96.1% for RRT patients in the lowest quartile of the multiple deprivation index, compared to 90.5% in the GM reference population. CONCLUSION: Bespoke COVID-19 vaccination programmes based on local clinical teams as trusted messengers can improve negative attitudes towards vaccination and reduce health inequalities.

Humoral Response in Hemodialysis Patients Following COVID-19 Vaccination and Breakthrough Infections during Delta and Omicron Variant Predominance.

BACKGROUND: The advancement of COVID-19 vaccination programs globally has been viewed as an integral strategy to reduce both the number of COVID-19 cases and consequential complications of COVID-19, particularly for high-risk patient groups. There are limited data on the antibody response and protection from disease infection and severity in patients requiring hemodialysis (HD) following COVID-19 vaccination during the Delta and Omicron variant predominance. We conducted a study aiming to evaluate humoral immunity derived from two different COVID-19 vaccines administered to our in-centre HD population and investigated the characteristics of breakthrough COVID-19 infections occurring post-vaccination within this population. METHODS: This is a prospective observational study including patients receiving HD at Salford Royal Hospital. The first and second doses of COVID-19 vaccinations (Pfizer BioNTech BNT162b2 or Oxford AstraZeneca ChAdOx1 nCoV-19) were administered to this patient cohort since January 2021. The incidence of any breakthrough COVID-19 infections occurring in double vaccinated patients between 1 April 2021 and 15 January 2022 was recorded. Patients were screened weekly with nasal and pharyngeal nasopharyngeal swabs for real-time Reverse Transcription Polymerase Chain Reaction (rRT-PCR) for COVID-19, whilst SARS-CoV-2 antibody testing was performed alongside monthly routine HD bloods. RESULTS: Four hundred eleven patients receiving HD were included in this study, of which 170 of 178 patients (95.5%) with available data on antibody status following two doses of the Pfizer BioNTech BNT162b2 vaccination had detectable antibody response, whilst this was the case for 97 of 101 patients (96.1%) who received two doses of the Oxford AstraZeneca ChAdOx1 nCoV-19 vaccine. For 12 seronegative patients who received a booster vaccine (third dose), nine seroconverted, while one remained negative and two were not tested. No statistically significant differences were observed with regards to antibody status between those receiving Pfizer BioNTech BNT162b2 and Oxford AstraZeneca ChAdOx1 nCoV-19 vaccines. Sixty-three of 353 patients with two doses of COVID-19 vaccination had breakthrough COVID-19 infection (40 during Delta and 23 during Omicron variant predominance). Of the 40 patients during the delta period, five were admitted into hospital and there were two reported deaths due to COVID-19-related illness. There were no COVID-19 associated hospitalizations or deaths during the Omicron variant predominance. CONCLUSIONS: The vast majority of HD patients who received two doses of the Pfizer BioNTech BNT162b2 or Oxford AstraZeneca ChAdOx1 nCoV-19 vaccinations developed detectable antibody responses. Our results support the value of booster vaccination with mRNA-based COVID-19 vaccine in HD patients and highlight the need for ongoing surveillance programmes with rRT-PCR and antibody testing for timely detection of positive cases.

Humoral Response in Hemodialysis Patients Following COVID-19 Vaccination and Breakthrough Infections during Delta and Omicron Variant Predominance

Background: The advancement of COVID-19 vaccination programs globally has been viewed as an integral strategy to reduce both the number of COVID-19 cases and consequential complications of COVID-19, particularly for high-risk patient groups. There are limited data on the antibody response and protection from disease infection and severity in patients requiring hemodialysis (HD) following COVID-19 vaccination during the Delta and Omicron variant predominance. We conducted a study aiming to evaluate humoral immunity derived from two different COVID-19 vaccines administered to our in-centre HD population and investigated the characteristics of breakthrough COVID-19 infections occurring post-vaccination within this population. Methods: This is a prospective observational study including patients receiving HD at Salford Royal Hospital. The first and second doses of COVID-19 vaccinations (Pfizer BioNTech BNT162b2 or Oxford AstraZeneca ChAdOx1 nCoV-19) were administered to this patient cohort since January 2021. The incidence of any breakthrough COVID-19 infections occurring in double vaccinated patients between 1 April 2021 and 15 January 2022 was recorded. Patients were screened weekly with nasal and pharyngeal nasopharyngeal swabs for real-time Reverse Transcription Polymerase Chain Reaction (rRT-PCR) for COVID-19, whilst SARS-CoV-2 antibody testing was performed alongside monthly routine HD bloods. Results: Four hundred eleven patients receiving HD were included in this study, of which 170 of 178 patients (95.5%) with available data on antibody status following two doses of the Pfizer BioNTech BNT162b2 vaccination had detectable antibody response, whilst this was the case for 97 of 101 patients (96.1%) who received two doses of the Oxford AstraZeneca ChAdOx1 nCoV-19 vaccine. For 12 seronegative patients who received a booster vaccine (third dose), nine seroconverted, while one remained negative and two were not tested. No statistically significant differences were observed with regards to antibody status between those receiving Pfizer BioNTech BNT162b2 and Oxford AstraZeneca ChAdOx1 nCoV-19 vaccines. Sixty-three of 353 patients with two doses of COVID-19 vaccination had breakthrough COVID-19 infection (40 during Delta and 23 during Omicron variant predominance). Of the 40 patients during the delta period, five were admitted into hospital and there were two reported deaths due to COVID-19-related illness. There were no COVID-19 associated hospitalizations or deaths during the Omicron variant predominance. Conclusions: The vast majority of HD patients who received two doses of the Pfizer BioNTech BNT162b2 or Oxford AstraZeneca ChAdOx1 nCoV-19 vaccinations developed detectable antibody responses. Our results support the value of booster vaccination with mRNA-based COVID-19 vaccine in HD patients and highlight the need for ongoing surveillance programmes with rRT-PCR and antibody testing for timely detection of positive cases.

A Quality Improvement Project to Minimize COVID-19 Infections in Patients Receiving Haemodialysis and the Role of Routine Surveillance Using Nose and Throat Swabs for SARS-CoV-2 rRT-PCR and Serum Antibody Testing.

BACKGROUND: Patients receiving in-centre haemodialysis (ICHD) are highly vulnerable to COVID-19. OBJECTIVE: We created a quality improvement (QI) project aimed to eliminate outbreaks of COVID-19 in haemodialysis units and evaluated the utility of surveillance rRT-PCR test and SARS-CoV-2 serum antibodies for prompt identification of patients infected with COVID-19. METHODS: A multifaceted QI programme including a bundle of infection prevention control (IPC) measures was implemented across 5 ICHD units following the first wave of the pandemic in June 2020. Primary outcomes evaluated before and after QI implementation were incidence of outbreaks and severe COVID-19 illness defined as COVID-19-related death or hospitalization. Secondary outcomes included the proportion of patients identified in the pre-symptomatic/asymptomatic phase on surveillance rRT-PCR screening and the incidence and longevity of SARS-CoV-2 antibody response. RESULTS: Following the implementation of the QI project, there were no further outbreaks. Pre- and post-implementation comparison showed a significant reduction in COVID-19-related mortality and hospitalization (26 vs. 13 events, respectively, p < 0.001). Surveillance rRT-PCR screening identified 39 asymptomatic or pre-symptomatic cases out of a total of 59 rRT-PCR-positive patients (39/59, 66%). SARS-CoV-2 antibody levels were detected in 72/74 (97%) rRT-PCR-positive patients. Amongst rRT-PCR-positive patients diagnosed before August 2020, 96% had detectable antibodies until January 2021 (days from the rRT-PCR test to last antibody testing, 245-280). CONCLUSIONS: Systematic implementation of a bundle of IPC measures using QI methodology and surveillance rRT-PCR eliminated outbreaks in HD facilities. Most HD patients mount and sustain antibody response to COVID-19 for over 8 months.

Occupational exposure of healthcare workers to COVID-19 and infection prevention control measures in haemodialysis facilities in North West of England.

COVID-19 infection rates in haemodialysis (HD) facilities are extremely high and are attributed to the high burden of comorbidities of HD patients coupled with inability to self-isolate needing thrice weekly attendance for HD treatment. Healthcare workers (HCW) in HD facilities are at risk of occupational exposure to COVID-19. Infection prevention control (IPC) measures were introduced during the pandemic aiming at reducing transmission and occupational exposure risk of COVID-19. Here we describe the results of our baseline and follow up occupational exposure audit in a renal centre in the North West of England following the implementation of a multifaceted IPC bundle.

Investigating the utility of COVID-19 antibody testing in end-stage renal disease patients receiving haemodialysis: a cohort study in the United Kingdom.

BACKGROUND: End-stage renal disease (ESRD) patients receiving haemodialysis (HD) are a vulnerable group of patients with increased mortality from COVID-19. Despite improved understanding, the duration of host immunity following COVID-19 infection and role of serological testing alone or in addition to real-time reverse transcription polymerase chain reaction (rRT-PCR) testing in the HD population is not fully understood, which this study aimed to investigate. METHODS: There were two parts to this study. Between 15th March 2020 to 15th July 2020, patients receiving HD who tested positive on rRT-PCR for SARS-CoV-2 were recruited into the COVID-19 arm, whilst asymptomatic patients without a previous diagnosis of COVID-19 were recruited to the epidemiological arm of the Salford Kidney Study (SKS). All patients underwent monthly testing for anti-SARS-CoV-2 antibodies as per routine clinical practice since August 2020. The aims were twofold: firstly, to determine seroprevalence and COVID-19 exposure in the epidemiological arm; secondly, to assess duration of the antibody response in the COVID-19 arm. Baseline characteristics were reviewed between groups. Statistical analysis was performed using SPSS. Mann-Whitney U and Chi-squared tests were used for testing significance of difference between groups. RESULTS: In our total HD population of 411 patients, 32 were PCR-positive for COVID-19. Of the remaining patients, 237 were recruited into the SKS study, of whom 12 (5.1%) had detectable anti-SARS-CoV-2 antibodies. Of the 32 PCR-positive patients, 27 (84.4%) were symptomatic and 25 patients admitted to hospital due to their symptoms. Of the 22 patients in COVID-19 arm that underwent testing for anti-SARS-CoV-2 IgG antibodies beyond 7 months, all had detectable antibodies. A higher proportion of the patients with COVID-19 were frail compared to patients without a diagnosis of COVID-19 (64.3% vs 34.1%, p = 0.003). Other characteristics were similar between the groups. Over a median follow up of 7 months, a higher number of deaths were recorded in patients with a diagnosis of COVID-19 compared to those without (18.7% vs 5.9%, p = 0.003). CONCLUSIONS: Serological testing in the HD population is a valuable tool to determine seroprevalence, monitor exposure, and guide improvements for infection prevention and control (IPC) measures to help prevent local outbreaks. This study revealed HD patients mount a humoral response detectable until at least 7 months after COVID-19 infection and provides hope of similar protection with the vaccines recently approved.

Safely reducing haemodialysis frequency during the COVID-19 pandemic.

BACKGROUND: Patients undergoing haemodialysis (HD) are at higher risk of developing worse outcomes if they contract COVID-19. In our renal service we reduced HD frequency from thrice to twice-weekly in selected patients with the primary aim of reducing COVID 19 exposure and transmission between HD patients. METHODS: Dialysis unit nephrologists identified 166 suitable patients (38.4% of our HD population) to temporarily convert to twice-weekly haemodialysis immediately prior to the peak of the COVID-19 pandemic in our area. Changes in pre-dialysis weight, systolic blood pressure (SBP) and biochemistry were recorded weekly throughout the 4-week project. Hyperkalaemic patients (serum potassium > 6.0 mmol/L) were treated with a potassium binder, sodium bicarbonate and received responsive dietary advice. RESULTS: There were 12 deaths (5 due to COVID-19) in the HD population, 6 of which were in the twice weekly HD group; no deaths were definitively associated with change of dialysis protocol. A further 19 patients were either hospitalised and/or developed COVID-19 and thus transferred back to thrice weekly dialysis as per protocol. 113 (68.1%) were still receiving twice-weekly HD by the end of the 4-week project. Indications for transfer back to thrice weekly were; fluid overload (19), persistent hyperkalaemia (4), patient request (4) and compliance (1). There were statistically significant increases in SBP and pre-dialysis potassium during the project. CONCLUSIONS: Short term conversion of a large but selected HD population to twice-weekly dialysis sessions was possible and safe. This approach could help mitigate COVID-19 transmission amongst dialysis patients in centres with similar organisational pressures.