LAUSR

Abstract Background and Aims The impact of the newly discovered severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causing coronavirus disease-19 (COVID-19) in hemodialysis patients remains poorly characterized. Some hemodialysis techniques reduce systemic inflammation but their impact on COVID-19 has not been addressed. The aim of this prospective study was to evaluate factors associated to mortality in COVID-19 hemodialysis patients, including the impact of reducing interleukin-6 using a cytokine adsorbent filter. Method This is a prospective single-center study including 16 hemodialysis patients with COVID-19. All were dialyzed using a polymethyl methacrylate (PMMA) filter. Interleukin-6 levels were obtained before and after the first admission hemodialysis session and at one week. Also we collected serum samples from 8 patients of our unit as controls: 4 in online hemodiafiltration (OLHDF) and 4 in high-flux hemodialysis Baseline comorbidities, laboratory values, chest X-ray and treatments were recorded and compared between survivors and non-survivors. Results Sixteen patients were included (13 males, mean age 72±15 years). Four patients (25%) died. Factors associated to mortality were dialysis vintage (p=0.01), the presence of infiltrates in chest X-ray (p=0.032), serum C-reactive protein (p=0.05) and lactate dehydrogenase (p=0.02) at one week, the requirement of oxygen therapy (p=0.02) and the use of anticoagulation (p<0.01). At admission, post-dialysis interleukin-6 levels were higher (p<0.01) in non-survivors and these patients differed from survivors in the reduction of interleukin-6 levels during the dialysis session despite using a PMMA filter (survivors vs non survivors (25 [17-53]% vs -3 [-109-12] %, p=0.04). Conclusion In hemodialysis COVID-19 patients, a positive balance of interleukin-6 during the session was associated to higher mortality.MO664   Figure 1: Median reduction in serum interlekin-6 during the first hemodialysis session with a PMMA filter at admission was higher in surviving than in non-surviving COVID-19 patients. A negative value means that serum interleukin-6 increased during dialysis.