The immunological mechanisms that modulate immune response to SARS-CoV-2 infection remain elusive. Little is known on the magnitude and the durability of antibody response against COVID-19. There is consensus that patients with immune dysfunction, such as dialysis patients, may be unable to mount a robust and durable humoral immunity after infections. Recent studies showed that dialysis patients seroconverted after COVID-19, but data on the durability of the immune response are missing. We reported the data of a durable anti-spike protein seroconversion after natural SARS-CoV-2 infection in three patients on hemodialysis with a mean age of 67.2 AE 13.8 years. A mean antibody titer of 212.6 AE 174.9 UA/ml (Liaison ® , DiaSorin) was found after one year (range, 366-374 days) from the diagnosis of COVID-19. In conclusion, this case series provided evidence that patients Modena COVID-19 Working Group (MoCo19) includes:

The development of effective anti-COVID-19 vaccines has enormously minimized the risk of severe illness in most immunocompetent patients. However, unvaccinated patients and non-responders to the COVID-19 vaccine are at risk of shortand long-term consequences. In these patients, the outcome of COVID-19 relies on an interplay of multiple factors including age, immunocompetence, comorbidities, inflammatory response triggered by the virus as well as the virulence of SARS-CoV-2 variants. Generally, COVID-19 is asymptomatic or mildly symptomatic in young people, but it may manifest with respiratory insufficiency requiring mechanical ventilation in certain susceptible groups of patients. Furthermore, severe SARS-CoV-2 infection induces multiorgan failure syndrome by affecting liver, kidney heart and nervous system. Since December 2019, multiple drugs have been tested to treat COVID-19, but only a few have been proven effective to mitigate the course of the disease that continues to cause death and comorbidity worldwide. Current treatment of COVID-19 patients is essential-SUMMARY ly based on the administration of supportive oxygen therapy and the use of specific drugs such as steroids, anticoagulants, antivirals, anti-SARS-CoV-2 antibodies and immunomodulators. However, the rapid spread of new variants and the release of new data coming from the numerous ongoing clinical trials have created the conditions for maintaining a continuous updating of the therapeutic management of COVID-19 patients. Furthermore, we believe that a well-established therapeutic strategy along with the continuum of medical care for all patients with COVID-19 is pivotal to improving disease outcomes and restoring healthcare care fragmentation caused by the pandemic. This narrative review, focusing on the therapeutic management of COVID-19 patients, aimed to provide an overview of current therapies for (i) asymptomatic or mildly/moderate symptomatic patients, (ii) hospitalized patients requiring low-flow oxygen, (iii) highflow oxygen and (iv) mechanical ventilation.

IntroductionSome hemodialysis patients are reluctant to COVID-19 for the development of adverse events (AEs). The aim of this study was to verify the safety of mRNA-1273 vaccine in hemodialysis patients.MethodsWe conducted a retrospective analysis of in-center hemodialysis patients who underwent mRNA-1273 vaccine from March 1st to April 30th, 2021. All AEs occurring after the first and the second doses were collected and classified as local or systemic.ResultsOverall, 126 patients on chronic maintenance dialysis without a prior COVID-19 diagnosis were vaccinated with two doses of mRNA-1273 vaccine. Mean age was 68 (IQR, 54,7-76) years and 53.6% of patients were aged ≥ 65 years. During the observational period of 68 (IQR, 66-70) days, AEs occurred in 57.9% and 61.9% of patients after the first dose and second dose, respectively. The most common AEs were: injection-site pain (61.9%), erythema (4.8%), itching (4.8%), swelling (16.7%), axillary swelling/tenderness (2.4%), fever (17.5%) headache (7.9%), fatigue (23.8%), myalgia (17.5%), arthralgia (12.7%), dyspnoea (2.4%), nausea/vomiting (7.1%), diarrhoea (5.6%), shivers (4%) and vertigo (1.6%).The rates of local AEs were similar after the first and second doses (P=0.8), whereas systemic AEs occurred more frequently after the second dose (P=0.001). Fever (P=0.03), fatigue (P=0.02) and nausea/vomiting (P=0.03) were significantly more frequent after the second dose of the vaccine. There were no age-related differences in the rate of AEs. Overall, vaccine-related AEs in hemodialysis patients seem to be lower than in the general population.ConclusionRNA-1273 vaccine was associated with the development of transient AEs after the first (57.9%) and second doses (61.9%) in patients on chronic maintenance hemodialysis. Systemic AEs were more common after the second dose. Overall, all AEs lasted for a few days, without any apparent sequelae.

Insufficient vaccine coverage and dominance of the more transmissible SARS-Cov-2 variants are the leading causes of the continued spread of COVID-19 worldwide. To curb the surge in infections, COVID-19 vaccination has been advocated as a prioritizing measure especially for frail populations and people at high risk of exposure. Patients on in-center maintenance hemodialysis embody both conditions. They are at high risk of severe COVID-19 consequences due to their advanced age and weakened immune system and carry an increased risk of SARS-CoV-2 transmission within shared dialysis rooms and public vehicles. Vaccination of the entire hemodialysis population is therefore the most effective strategy to protect patients from the dire consequences of COVID-19. Unfortunately, a minority of patients still express COVID-19 vaccine hesitancy. The management of this group of patients, who have the full right to hemodialysis treatment, poses demanding problems from a patient safety perspective. The placement of unvaccinated patients within the dialysis room and the protection of all vaccinated patients are some of the most urgent problems the nephrologist faces during the COVID-19 pandemic. In light of these COVID-19-driven changes, an ethical reflection on the management of unvaccinated patients appears crucial to act responsibly and contribute to the health promotion of dialysis patients.

Introduction There are limited data on the effects of COVID-19 on peritoneal dialysis (PD) patients. This study aimed to describe the impact of COVID-19 on the PD population. Methods A monocentric retrospective observational study was conducted on 146 consecutive PD patients followed from January 2020 to March 2022 at the University Hospital of Modena, Italy. Results Twenty-seven (18.4%) PD patients experienced 29 episodes of SARS-CoV-2 infection, corresponding to an incidence rate of 0.16 episodes/patient-year. Median age of COVID-19 patients was 60.4 (interquartile range [IQR] 50.2–66.5) years. In unvaccinated patients (n. 9), COVID-19 was always symptomatic and manifested with fever (100%) and cough (77.7%). COVID-19 caused hospital admission of three (33.3%) patients and two (22.2%) died of septic shock. COVID-19 was symptomatic in 83.3% of vaccinated subjects (n.18) and manifested with fever (61.1%) and cough (55.6%). Hospital admission occurred in 27.8% of the subjects but all were discharged home. Median SARS-CoV-2 shedding was 32 and 26 days in the unvaccinated and vaccinated groups, respectively. At the end of the follow-up, COVID-19 triggered the shift from PD to HD in two subjects without affecting the residual renal function of the remaining patients. Overall, COVID-19 caused an excess death of 22.2%. COVID-19 vaccination refusal accounted for only 1.6% in this cohort of patients. Conclusion COVID-19 incident rate was 0.16 episodes/patient-year in the PD population. About one-third of the patients were hospitalized for severe infection. Fatal outcome occurred in two (7.4%) unvaccinated patients. A low vaccination refusal rate was observed in this population. Supplementary Information The online version contains supplementary material available at 10.1007/s10157-022-02283-0.