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In this article the authors discuss the developments in the diagnosis of latent tuberculosis infection (LTBI) in patients who undergo renal replacement therapy. The authors analyse the results of a comparison between the tuberculin skin test (TST) and new in vitro diagnostic methods for LTBI diagnosis. They claim that TST is the usual method to diagnose LTBI. They also cite techniques on the market for in vitro diagnosis of TBI such as QuantiFERON-TB-Gold In Tube and T-SPOT.TB.

Background and Objective: To evaluate the effectiveness and safety of intradialytic parenteral nutrition (IDPN) on different nutritional outcomes., Methods: This was a retrospective analysis for a "routinely collected data bank" in a multicenter cohort, conducted on consecutive malnourished or at-risk of malnutrition patients with chronic kidney disease on hemodialysis who underwent IDPN with a three-in-one parenteral nutrition formula for a period ≥ 2 weeks. The primary endpoint was the mean change in the malnutrition inflammation score (MIS) score between baseline and the last follow-up visit on IDPN., Results: Fifty-six patients were included. The mean age was 72.4 ± 12.0 years, and 24 (42.9%) were women. In the overall study sample, MIS significantly decreased from 16.4 (95%CI: 15.3-17.65) at baseline to 14.3 (95%CI: 12.8-15.8) at the last follow-up visit on IDPN ( p = 0.0019). Fifteen (26.8%) patients achieved a MIS reduction ≥ 5 points after IDPN. As compared to baseline, IDPN significantly reduced the proportion of patients with protein-energy wasting (PEW) (89.3% versus 66.1%, respectively, p = 0.0023). Regarding analytical parameters, serum albumin ( p = 0.0003) and total proteins ( p = 0.0024) significantly increased after IDPN administration. Throughout the study's follow-up period, 45 (80.4%) patients reported experiencing some type of adverse event., Conclusions: IDPN was associated with a significant improvement in the nutritional profile. Notably, our research found that the administration of IDPN over a duration > 3 months significantly improved the nutritional status of patients evaluated by the MIS test.

Hemodialysis (HD) is a treatment with a significant environmental impact. One dialysis cycle is equivalent to the daily consumption of 3.5-4 people, and the average annual electricity consumption of a center is equivalent to that of approximately 2.5-3 households (9 kWh/day per household). The carbon footprint (kg CO2 equivalent) measures direct and indirect greenhouse gas emissions and is influenced by the production of the various materials used, their transport, patients, and healthcare personnel. In this context, it is necessary to understand the real impact of each center on the environment and act sustainably. The aim of this review is to analyze the environmental footprint generated by dialysis, rethink processes, and propose management strategies to provide tools applicable to any unit to reduce the negative impact of this activity. Each center must measure and monitor indicators, set its own standards, design improvement plans, and carry out annual monitoring in a multidisciplinary manner., Competing Interests: Declaration of competing interest The authors declare that they have no conflicts of interest., (Copyright © 2024 Sociedad Española de Nefrología. Published by Elsevier España, S.L.U. All rights reserved.)

Background: Cardiovascular disease (CVD) remains the most common cause of mortality in chronic kidney disease (CKD) patients. Several studies suggest that the Mediterranean diet reduces the risk of CVD due to its influence on endothelial function, inflammation, lipid profile, and blood pressure. Integrating metabolomic and proteomic analyses of CKD could provide insights into the pathways involved in uremia-induced CVD and those pathways modifiable by the Mediterranean diet., Methods: We performed metabolomic and proteomic analyses on serum samples from 19 patients with advanced CKD (aCKD) and 27 healthy volunteers. The metabolites were quantified using four different approaches, based on their properties. Proteomic analysis was performed after depletion of seven abundant serum proteins (Albumin, IgG, antitrypsin, IgA, transferrin, haptoglobin, and fibrinogen). Integrative analysis was performed using MetaboAnalyst 4.0 and STRING 11.0 software to identify the dysregulated pathways and biomarkers., Results: A total of 135 metabolites and 75 proteins were differentially expressed in aCKD patients, compared to the controls. Pathway enrichment analysis showed significant alterations in the innate immune system pathways, including complement, coagulation, and neutrophil degranulation, along with disrupted linoleic acid and cholesterol metabolism. Additionally, certain key metabolites and proteins were altered in aCKD patients, such as glutathione peroxidase 3, carnitine, homocitrulline, 3-methylhistidine, and several amino acids and derivatives., Conclusions: Our findings reveal significant dysregulation of the serum metabolome and proteome in aCKD, particularly in those pathways associated with endothelial dysfunction and CVD. These results suggest that CVD prevention in CKD may benefit from a multifaceted approach, including dietary interventions such as the Mediterranean diet.

Background: New versions of the polyester polymer alloy (PEPA) membrane have appeared over the years, with increases in both the pore size and the amount of polyvinylpyrrolidone (PVP) to optimize hydrophilicity performance. This study aimed to assess the efficacy of the most recently developed PEPA dialyzer, the FDY series, in hemodialysis (HD) modality in terms of uremic toxin removal and albumin loss and to compare it with that of several high-flux dialyzers currently used in HD and post-dilution hemodiafiltration (HDF) treatments., Methods: A prospective study was carried out in 21 patients. All patients underwent six dialysis sessions with the same routine dialysis parameters; only the dialyzer and/or the dialysis modality varied: FX80 in HD, FDY 180 in HD, Clearum HS17 in HDF, Elisio 19H in HDF, Vitapes 180 in HDF, and FX80 in post-dilution HDF. The reduction ratios (RR) of urea, creatinine, ß 2 -microglobulin, myoglobin, κFLC, prolactin, α 1 -microglobulin, α 1 -acid glycoprotein, λFLC, and albumin were compared intraindividually. Dialysate albumin loss was also measured., Results: Both membranes FDY and FX80 are high-flux dialyzers and are applied here in high-flux HD. The average RR of β 2 -microglobulin was slightly lower in the two HD treatments than in the HDF treatments. Comparison of dialysis treatments revealed that the PEPA FDY dialyzer in the HD modality was more effective than the FX80 dialyzer in high-flux HD and was as effective as post-dilution HDF, especially in terms of myoglobin, κFLC, prolactin, α 1 -microglobulin, and λFLC RRs. The FDY treatments obtained similar albumin RR in blood and slightly higher dialysate albumin loss, although the values were clinically acceptable., Conclusions: The most recently developed PEPA dialyzers in the HD modality were as effective as all treatments in the HDF modality and were clearly superior to high-flux helixone HD treatment. These results confirm that this dialyzer should be categorized within the medium cut-off (MCO) membrane classification., (© 2024 The Authors. Artificial Organs published by International Center for Artificial Organ and Transplantation (ICAOT) and Wiley Periodicals LLC.)

Introduction: New generation helixone dialyzers has recently been developed as part of the ongoing effort to improve dialyzer hemocompatibility and avoid adverse reactions to synthetic dialyzers. This study aimed to assess the performance and albumin loss of this new dialyzer series in hemodiafiltration and compare it with the previous generation helixone series., Material and Methods: A prospective study was conducted in 19 patients. Each patient underwent eight dialysis sessions with the same routine dialysis parameters; only the dialyzer varied: FX60 CorDiax, FX CorAL 60, FX600 CorDiax, FX CorAL 600, FX80 CorDiax, FX CorAL 80, FX800 CorDiax, and FX CorAL 800. The reduction ratios (RR) of urea, creatinine, ß 2 -microglobulin, myoglobin, kappa-free immunoglobulin light chains (κFLC), prolactin, α 1 -microglobulin, α 1 -acid glycoprotein, lambda immunoglobulin light chains (λFLC), and albumin were compared intra-individually. Dialysate albumin loss was also measured., Results: All treatments were well tolerated. The mean amount of replacement fluid ranged from 31 to 34 L. Comparison of dialysis treatments showed no differences between small molecules and even up to those the size of β2-microglobulins. Little differences were found between myoglobin, κFLC, prolactin, α 1 -microglobulin, and λFLC RRs, and only FX80 CorDiax was slightly superior to the others. Mean dialysate albumin losses were similar, with less than 2.5 g lost in each dialyzer. The FX80 CorDiax showed slightly higher global removal scores than the other dialyzers evaluated, except for FX CorAL 800., Conclusion: The new generation helixone dialyzers series has been updated to minimise the risk of adverse reactions, while maintaining the effectiveness and albumin loss achieved by the previous most advanced helixone generation., (Copyright © 2024. Published by Elsevier España, S.L.U.)

Introduction: Changes in plasma sodium concentration ( p Na, expressed in mEq/L) are common in hemodialysis (HD) patients. Hemodialysis monitors can estimate p Na by using an internal algorithm based on ion dialysance measurements. The present study studies the accuracy of the correlation between the p Na estimated by the dialysis monitor and that measured by the biochemistry laboratory at our center., Material and Methods: A single-centre prospective observational study in patients on a chronic HD program with the 6008 CAREsystem monitor and standard sodium (138mmol/L) and bicarbonate (32mmol/L) prescriptions. Venous blood samples were drawn from each patient before and after each HD session to ensure inter- and intra-individual validity. The p Na was measured in the biochemistry laboratory using indirect potentiometry and simultaneously the estimated p Na by the HD monitor was recorded at the beginning and at the end of the HD session. For statistical analysis, a scatterplot was made, and Spearman's correlation quotient was calculated. In addition, the differences between both methods were represented as Bland-Altman diagrams., Results: The pre-dialysis p Na measured in the laboratory was 137.49±3.3, and that of the monitor, 137.96±2.91, with a correlation with R 2 value of 0.683 (p<0.001). The post-dialysis p Na measured in the laboratory was 137.08±2.23, and that of the monitor was 138.87±1.88, with an R 2 of 0.442 (p<0.001). On the Bland-Altman plots, the pre-dialysis p Na has a systematic error of 0.49, in favor of the monitor-estimated p Na, with a 95% confidence interval (CI) of (-3.24 to a 4.22). In the post-dialysis p Na, a systematic error of 1.79 with a 95% CI of (-1.64 to 5.22) was obtained., Conclusion: The correlation between the p Na estimated by Fresnius 6008 CAREsystem HD monitor and that measured by the laboratory is good, especially pre-dialysis measurements. Further studies should verify the external validity of these results., (Copyright © 2023 Sociedad Española de Nefrología. Published by Elsevier España, S.L.U. All rights reserved.)

Introduction: Introduction: Chronic kidney disease (CKD) is characterized by its high prevalence of malnutrition, difficult to detect as it is underestimated by the usual tools. There is no valid or hospital-level nutritional screening tool in Spanish to identify patients with CKD at risk of malnutrition. Objective: to translate and accomplish the transcultural adaptation of Jackson's questionnaire (Renal Inpatient Nutrition Screening Tool [Renal iNUT]) to Spanish, which detects the risk of malnutrition in CKD inpatients and compares it with other nutritional tools. Methods: phase 1: translation, back-translation and transcultural adaptation of the questionnaire from the English to the Spanish version. A pilot test was carried out by nursing staff together with a satisfaction questionnaire. Phase 2: comparison of Renal iNUT with Malnutrition Universal Screening Tool (MUST) and Subjective Global Assessment (SGA). Results: phase 1: the nursing staff's perception was highly favorable. They found it easy or very easy to use and 90 % of them did it in a maximum of ten minutes. Phase 2: from 48 patients included, Renal iNUT detected 44 % at low risk of malnutrition, 28 % at intermediate risk and 28 % at high risk. Increased sensitivity of Renal iNUT (p < 0.007) vs MUST (62.5 vs 33.3 %) and similar specificity (87.1 vs 90.6 %) were found, together with an acceptable correlation compared to SGA (r = 0.75, 95 % CI: 0.67 to 0.83). Conclusions: the Spanish version of Renal iNUT is a useful and easy-to-understand tool for health professionals. We also confirm its good correlation with SGA, with greater sensitivity than MUST for the risk of malnutrition detection in CKD inpatients.

Introduction: The sodium gradient during hemodialysis sessions is one of the key factors in sodium balance in patients with dialysis-dependent chronic kidney disease; however, until the appearance of the new monitors with sodium modules, the differences between prescribed and measured sodium have been understudied. The present study aimed to compare the impact on the measured conductivity and the initial and final plasma sodium after changing the 5008 Cordiax to the new 6008 Cordiax monitor., Material and Methods: 106 patients on hemodialysis were included. Each patient underwent 2 dialysis sessions in which only the monitor was varied. The variables collected were dialysate, sodium and bicarbonate prescribed, real conductivity, initial and final plasma sodium measured, and the calculated sodium gradient (ΔPNa)., Results: The change of dialysis monitor showed small but statistically significant differences in the initial (138.14mmol/L with 5008 vs. 138.81mmol/L with 6008) and final plasma sodium (139.58mmol/L vs. 140.97mmol/L), as well as in the actual conductivity obtained (13.97 vs. 14.1mS/cm). The ΔPNa also increased significantly., Conclusion: The change from 5008 to 6008 monitor is associated with increased conductivity, leading the patient to end the sessions with higher plasma sodium and ΔPNa. Knowing and confirming this change will allow us to individualize the sodium prescription and avoid possible undesirable effects. It could be the preliminary study to explore the new sodium biosensor incorporated into the new generation of monitors., (Copyright © 2024. Published by Elsevier España, S.L.U.)

Background: The number of frail patients of advanced age with end-stage kidney disease (ESKD) undergoing hemodialysis is increasing globally. Here we evaluated a frailty screening program of ESKD patients starting hemodialysis, and subsequent multidisciplinary interventions., Methods: This was a prospective observational study of ESKD patients in a hemodialysis program. Patients were evaluated for frailty (Fried frail phenotype) before and after a 12-month period. Patients followed standard clinical practice at our hospital, which included assessment and multidisciplinary interventions for nutritional (malnutrition-inflammation score, protein-energy wasting), physical [short physical performance battery (SPPB)] and psychological status., Results: A total of 167 patients (mean ± standard deviation age 67.8 ± 15.4 years) were screened for frailty, and 108 completed the program. At screening, 27.9% of the patients were frail, 40.0% pre-frail and 32.1% non-frail. Nutritional interventions (enrichment, oral nutritional supplements, intradialytic parenteral nutrition) resulted in stable nutritional status for most frail and pre-frail patients after 12 months. Patients following recommendations for intradialytic, home-based or combined physical exercise presented improved or stable in SPPB scores after 12 months, compared with those that did not follow recommendations, especially in the frail and pre-frail population ( P  = .025). A rate of 0.05 falls/patient/year was observed. More than 60% of frail patients presented high scores of sadness and anxiety., Conclusions: Frailty screening, together with coordinated interventions by nutritionists, physiotherapists, psychologists and nurses, preserved the health status of ESKD patients starting hemodialysis. Frailty assessment helped in advising patients on individual nutritional, physical or psychological needs., Competing Interests: The authors declare no financial support for the project. F.M. has received consultancy fees and lecture fees from Baxter, Fresenius Medical Care, Medtronic, Nipro, Toray and Vifor. The other authors declare no conflicts of interest., (© The Author(s) 2023. Published by Oxford University Press on behalf of the ERA.)

The hemoconcentration effect for middle weight solutes in hemodialysis is corrected by oversimplified methods based on hematocrit changes or distribution volume variations. Here we implemented a variable volume dual pool kinetic model targeted at obtaining a precise correction factor equation for extracellularly distributed solutes based on relevant kinetic parameters such as the ultrafiltration to dry weight ratio UF/DW, the dialyzer clearance, K d , the intercompartment mass-transfer coefficient, K c , and the central compartment to extracellular volume ratio, α. More than 300,000 solutions of the model were computed, performing a sweep among physiological values of the proposed kinetic parameters, resulting in a linear regression denoted by the expression f corr  = 1.0707 - 5.2246 (UF/DW) - 0.0005 K d - 0.0004 K c - 0.0007 α, with an excellent coefficient of determination R 2  = 0.983. The presented f corr provides a substantial extension of the currently implemented methods to estimate the hemoconcentration factor for middle and high molecular weight extracellular distributed solutes in hemodialysis.

Background: A key feature of dialysis treatment is the prescription of dialysate sodium (Na). This study aimed to describe the practical implementation of a new automated dialysate Na control biosensor and to assess its tolerance and the beneficial clinical effects of isonatraemic dialysis., Methods: A prospective study was carried out in 86 patients who, along with their usual parameters, received the following five consecutive phases of treatment for 3 weeks each: phase 0: baseline 5008 machine; phases 1 and 2: 6008 machine without activation of the Na control biosensor and the same fixed individualized Na dialysate prescription or adjusted to obtain similar conductivity to phase 0; phases 3 and 4: activated Na control to isonatraemic dialysis (Na dialysate margins 135-141 or 134-142 mmol/L)., Results: When the Na control was activated, the few episodes of cramps or hypotension disappeared when the lower dialysate Na margin was increased by 1 or 2 mmol/L. The activated Na control module showed significant differences compared with baseline and the non-activated Na module in final serum Na values, diffusive Na balance, and changes in pre- to postdialysis plasma Na values. The mean predialysis systolic blood pressure value was significantly lower in phase 4 than in phase 1. There were no significant differences in total Na balance in the four 6008 phases evaluated., Conclusions: The implementation of the automated dialysate Na control module is a useful new tool, which reduced the diffusive load of Na with good tolerance. The module had the advantages of reducing thirst, interdialytic weight gain and intradialytic plasma Na changes., Competing Interests: The authors declare no financial support for the project. F.M. has received consultancy fees and lecture fees from Baxter, Fresenius Medical Care, Medtronic, Nipro, Toray and Vifor. The other authors declare no conflicts of interest., (© The Author(s) 2023. Published by Oxford University Press on behalf of the ERA.)

Introduction: The medium cut-off Elisio HX dialyzer by Nipro became commercially available in Europe in 2021, but there are still no reports of in vivo data. This study aimed to evaluate the safety and efficacy of it compared with previously evaluated hemodialysis (HD), expanded HD (HDx), and postdilution hemodiafiltration (HDF) treatments., Methods: A prospective study was carried out on 18 patients who underwent 5 dialysis sessions: FX80 Cordiax in HD, Elisio H19 in HD, Elisio HX19 in HDx, Theranova 400 in HDx, and FX80 Cordiax in HDF. The reduction ratios of urea, creatinine, ß2-microglobulin, myoglobin, kappa FLC, prolactin, α1-microglobulin, α1-acid glycoprotein, lambda FLC, and albumin were compared. Dialysate albumin loss was measured., Results: The comparison between the different dialysis modalities revealed no difference for small molecules, but HDx and HDF were significantly more efficient than HD for medium and large molecule removal. The efficacy of Elisio HX19 dialyzer in HDx was similar to the Theranova 400, superior to both dialyzers in HD, and slightly lower than HDF. Albumin losses in dialysate with HD dialyzers were less than 1 g, but between 1.5 and 2.5 g in HDx and HDF. The global removal score (GRS) values with HDx treatments were statistically significantly higher than those with HD. The highest GRS was obtained with the helixone dialyzer in HDF., Conclusions: The new MCO dialyzer, Elisio HX, performs with excellent behavior and tolerance. It represents an upgrade compared to their predecessor and is very close to the removal capacity of HDF treatment., (© 2022 The Author(s). Published by S. Karger AG, Basel.)

Background: The clinical and epidemiological implications of abnormal immune responses in COVID-19 for latent tuberculosis infection (LTBI) screening are unclear., Methods: We reviewed QuantiFERON TB Gold Plus (QFT-Plus) results (36,709 patients) from July 2016 until October 2021 in Asturias (Spain). We also studied a cohort of ninety hospitalized patients with suspected/confirmed COVID-19 pneumonia and a group of elderly hospitalized patients with COVID-19 who underwent serial QFT-Plus and immune profiling testing., Results: The indeterminate QFT-Plus results rate went from 1.4% (July 2016 to November 2019) to 4.2% during the COVID-19 pandemic. The evolution of the number of cases with low/very low interferon-gamma (IFN-gamma) response in the mitogen tube paralleled the disease activity and number of deaths during the pandemic waves in our region (from March 2020 to October 2021). The percentages of positive QFT-plus patients did not significantly change before and during the pandemic (13.9% vs . 12.2%). Forty-nine patients from the suspected/confirmed COVID-19 pneumonia cohort (54.4%) had low/very low IFN-gamma response to mitogen, 22 of them (24.4%) had severe and critical pneumonia. None received immunosuppressants prior to testing. Abnormal radiological findings (P = 0.01) but not COVID-19 severity was associated with low mitogen response. Immune profiling showed a reduction of CD8 + T cells and a direct correlation between the number of EMRA CD8 + T-cells and IFN-gamma response to mitogen (P = 0.03)., Conclusion: Low IFN-gamma responses in mitogen tube of QFT-Plus often occur in COVID-19 pneumonia, which is associated with a low number of an effector CD8 + T-cell subset and does not seem to affect LTBI screening; however, this abnormality seems to parallel the dynamics of COVID-19 at the population level and its mortality., (© 2022 SEPAR. Published by Elsevier España, S.L.U. All rights reserved.)

This cross-sectional study aims to explore the prevalence of protein-energy wasting (PEW) in dialysis patients in Catalonia, Spain, using a new and practical online tool which enables rapid calculation and comparison with other nutritional scores., Methods: A web tool (Nutrendial) was created to introduce different variables and automatically calculate PEW, Malnutrition inflammation Score (MIS) and Subjective Global Assessment (SGA) in 1389 patients (88% in haemodialysis (HD)), 12% in peritoneal dialysis (PD) from different regions of Catalonia., Results: A prevalence of 23.3% (26% HD, 10.2% PD) of PEW was found, with a mean MIS score of 6 and SGA score of C in 7% of the patients. ROC analysis showed MIS as the best nutritional score to diagnose PEW (AUC 0.85). Albumin delivered lower diagnostic precision (AUC 0.77) and sensitivity (66%). A cut off point of 7 (86% sensitivity and 75% specificity) for MIS and 3.7 mg/dL for albumin were found to predict the appearance of PEW in this population. SGA B or C showed an 87% sensitivity and 55% specificity to diagnose PEW. Very low nutritional intervention (14%) was recorded with this tool in patients with PEW., Conclusions: This new online tool facilitated the calculation of PEW, enabling different professionals-including nephrologists, dieticians and nurses-to efficiently obtain insights into the nutritional status of the Catalonian dialysis population and implement the required nutritional interventions. MIS is the score with more sensitivity to diagnose PEW., Competing Interests: The authors declare no conflict of interest.

Background: Mechanical stretch of cancer cells can alter their invasiveness. During mechanical ventilation, lungs may be exposed to an increased amount of stretch, but the consequences on lung tumours have not been explored., Methods: To characterise the influence of mechanical ventilation on the behaviour of lung tumours, invasiveness assays and transcriptomic analyses were performed in cancer cell lines cultured in static conditions or under cyclic stretch. Mice harbouring lung melanoma implants were submitted to mechanical ventilation and metastatic spread was assessed. Additional in vivo experiments were performed to determine the mechanodependent specificity of the response. Incidence of metastases was studied in a cohort of lung cancer patients that received mechanical ventilation compared with a matched group of nonventilated patients., Results: Stretch increases invasiveness in melanoma B16F10luc2 and lung adenocarcinoma A549 cells. We identified a mechanosensitive upregulation of pathways involved in cholesterol processing in vitro , leading to an increase in pro-protein convertase subtilisin/kexin type 9 (PCSK9) and LDLR expression, a decrease in intracellular cholesterol and preservation of cell stiffness. A course of mechanical ventilation in mice harbouring melanoma implants increased brain and kidney metastases 2 weeks later. Blockade of PCSK9 using a monoclonal antibody increased cell cholesterol and stiffness and decreased cell invasiveness in vitro and metastasis in vivo . In patients, mechanical ventilation increased PCSK9 abundance in lung tumours and the incidence of metastasis, thus decreasing survival., Conclusions: Our results suggest that mechanical stretch promote invasiveness of cancer cells, which may have clinically relevant consequences. Pharmacological manipulation of cholesterol endocytosis could be a novel therapeutic target in this setting., Competing Interests: Conflict of Interest: I. López-Alonso reports postdoctoral fellowship from Ministerio de Ciencia, Innovación y Universidades, Spanish Government, outside the submitted work. C. López-Martínez reports PhD grant paid to institution from Ministerio de Universidades, Spain; student grant from AECC (Asociación Española Contra el Cáncer), outside the submitted work. L. Amado-Rodríguez reports postdoctoral fellowship paid to institution from Instituto de Salud Carlos III, Spain; mobility grant from CIBERES, Instituto de Salud Carlos III, Spain, outside the submitted work. A. Astudillo reports coordination of national platform Biobank and Biomodels ISCIII, HUB organoids, outside the submitted work. M. Arias-Guillén reports support for the present manuscript from Spanish Society of Pulmonology and Thoracic Surgery (SEPAR); grants from Carlos III Health Institute, and Spanish Society of Pulmonology and Thoracic Surgery (SEPAR), outside the submitted work. G.M Albaiceta reports support for the present manuscript from Instituto de Salud Carlos III; and holds a patent on a model of mechanical ventilator from Arcelor-Mittal. All other authors have nothing to disclose., (Copyright ©The authors 2022. For reproduction rights and permissions contact permissions@ersnet.org.)

Background: Recently, several pharmaceutical companies have developed new medium cut-off (MCO) dialyzers for expanded hemodialysis (HDx). This study aimed to compare the safety and efficacy of four MCO dialyzers, against each other and versus high-flux hemodialysis (HD) and post-dilution hemodiafiltration (HDF)., Methods: A prospective study was carried out on 23 patients who underwent six dialysis sessions: two sessions with the FX80 Cordiax in HD and HDF, and four HDx sessions with the Phylther 17-SD, Vie-18X, Elisio HX19 and Theranova 400 dialyzers. The reduction ratios (RRs) of urea, creatinine, β 2 -microglobulin, myoglobin, kappa free immunoglobulin light chain (κFLC), prolactin, α 1 -microglobulin, α 1 -acid glycoprotein, lambda (λFLC) and albumin were compared. Dialysate albumin loss was also measured., Results: The differences in efficacy between the evaluated dialyzers were minimal in small molecules and even up to the size of β 2 -microglobulin. The main differences were found between myoglobin, κFLC, prolactin, α 1 -microglobulin and λFLC RRs, in which all four MCO dialyzers, with similar efficacy, were clearly superior to HD and slightly inferior to HDF treatment. Albumin losses in the dialysate with HD dialyzers were <1 g and between 1.5 and 2.5 g in HDx and HDF. The global removal score values were similar in all four HDx treatments, and again significantly higher than those with HD., Conclusions: The results of the four MCO dialyzers evaluated in this study showed good efficiency, with no significant performance differences between them while being completely safe in terms of albumin loss. Likewise, the study confirms the superiority of HDx over high-flux HD with an efficacy close to that of post-dilution HDF., (© The Author(s) 2022. Published by Oxford University Press on behalf of the ERA.)

Background: Both metabolic acidosis and alkalosis increase hospitalizations, haemodynamic instability and mortality in haemodialysis patients. Unfortunately, current practices opt for a one-size-fits-all approach, leaving many patients either acidotic before or alkalotic after dialysis sessions. Therefore an individualized adjustment of these patients' dialysate bicarbonate prescriptions could reduce these acid-base imbalances., Methods: This is a prospective single-cohort study of patients on a chronic haemodiafiltration programme. The dialysate bicarbonate prescription was modified according to the pre- and post-dialysis total carbon dioxide (TCO 2 ) values of 19-25 mEq/L and ≤29 mEq/L, respectively, with an adjustment formula calculated with the data obtained from previously published work by our group. In addition, we analysed this adjustment's effect on plasma sodium, potassium, phosphorus, parathyroid hormone (PTH) and calcium., Results: At baseline, only 67.9% of patients were within the desired pre- and post-dialysis TCO 2 target range. As of the first month, every followed patient met the TCO 2 target range objective in pre-dialysis measurements and ˃95% met the post-dialysis TCO 2 target. At the end of the study, 75% of the patients were on dialysate bicarbonate of 32-34 mEq/L. There were no clinically significant changes in calcium, phosphate, PTH, sodium or potassium levels. Also, we did not notice any increase in intradialytic adverse events., Conclusions: We suggest an individualized adjustment of the dialysate bicarbonate concentration according to the pre- and post-dialysis TCO 2 values. With it, nearly every patient in our cohort reached the established range, potentially reducing their mortality risk., (© The Author(s) 2022. Published by Oxford University Press on behalf of the ERA.)

Chronic kidney disease (CKD) involves heterogeneous diseases that affect the renal structure and function. Malnutrition plays a crucial role during patients with CKD on hemodialysis (HD) treatment and is associated with an increased rate and duration of hospitalizations. The aim of this randomized, parallel, intervention-controlled trial was to assess whether the use of daily supplementation with a new nutritional product developed by the Grand Fontaine Laboratories improves the nutritional status and anthropometric parameters of stage 5 CKD patients, compared with standard renal dietary advice, after three months of follow-up. Dietary intake, anthropometric measurements, physical activity, and blood samples were collected at baseline and after three months of intervention. Significant improvements were observed within the intervention group in body weight (1.5 kg [95% CI: 0.9 to 2.12 kg]) and BMI (0.54 kg/m 2 [95% CI: 0.31 to 0.77]; p -value between groups, 0.002 and 0.006, respectively). In the control group, significant decreases were observed in transferrin saturation (-5.04% [95% CI: -8.88 to -1.21]) and alpha-tocopherol levels (-3.31 umol/L [95% CI: -6.30 to -0.32]). We concluded that daily dietary intake of a specific renal nutritional complement in CKD patients with or at risk of malnutrition may prevent deterioration in nutritional parameters.

Introduction: Haemodialysis (HD) allow depuration of uraemic toxins by diffusion, convection, and adsorption. Online haemodiafiltration (HDF) treatments add high convection to enhance removal. There are no prior studies on the relationship between convection and adsorption in HD membranes. The possible benefits conferred by intrinsic adsorption on protein-bound uraemic toxins (PBUTs) removal are unknown., Methods: Twenty-two patients underwent their second 3-days per week HD sessions with randomly selected haemodialysers (polysulfone, polymethylmethacrylate, cellulose triacetate, and polyamide copolymer) in high-flux HD and HDF. Blood samples were taken at the beginning and at the end of the treatment to assess the reduction ratio (RR) in a wide range of molecular weight uraemic toxins. A mid-range removal score (GRS) was also calculated. An elution protocol was implemented to quantify the amount of adsorbed mass (Mads) for each molecule in every dialyser., Results: All synthetic membranes achieved higher RR for all toxins when used in HDF, specially the polysulfone haemodialyser, resulting in a GRS = 0.66 ± 0.06 (p < 0.001 vs. cellulose triacetate and polyamide membranes). Adsorption was slightly enhanced by convection for all membranes. The polymethylmethacrylate membrane showed expected substantial adsorption of β2-microglobulin (MadsHDF = 3.5 ± 2.1 mg vs. MadsHD = 2.1 ± 0.9 mg, p = 0.511), whereas total protein adsorption was pronounced in the cellulose triacetate membrane (MadsHDF = 427.2 ± 207.9 mg vs. MadsHD = 274.7 ± 138.3 mg, p = 0.586) without enhanced PBUT removal., Discussion/conclusion: Convection improves removal and slightly increases adsorption. Adsorbed proteins do not lead to enhanced PBUTs depuration and limit membrane efficiency due to fouling. Selection of the correct membrane for convective therapies is mandatory to optimize removal efficiency., (© 2021 S. Karger AG, Basel.)

Objective: To analyse the accuracy of commonly used risk scores (PSI and CURB-65) in predicting mortality and need for ICU admission in Covid-19., Material and Methods: Prospective study of patients diagnosed with Covid-19 pneumonia. Patients were followed until home discharge or death. PSI, CURB-65, SMART-COP and MuLBSTA severity scores were assessed on admission. Risk scores were related to mortality and ICU admission., Results: About 249 patients, 143 males (57.4%) were included. The mean age was 65.6 + 16.1 years. Factors associates with mortality in the multivariate analysis were age > 80 years (OR: 13.9; 95% CI 3.8-51.1) (P = .000), lymphocytes < 800 (OR: 2.9; CI 95% 1.1-7-9) (P = .040), confusion (OR: 6.3; 95% CI 1.6-24.7) (P = .008) and NT-proBNP > 500 pg/mL (OR: 10.1; 95% CI 1.1-63.1) (P = .039). In predicting mortality, the PSI score: AUC 0.874 (95% CI 0.808-0.939) and the CURB-65 score: AUC 0.852 (95% CI 0.794-0.909) were the ones that obtained the best results. In the need for ICU admission, the SMART-COP score: AUC 0.749 (95% CI 0.695-0.820) and the MuLBSTA score: AUC 0.777 (95% CI 0.713-0.840) were the ones that obtained better results, with significant differences with PSI and CURB-65. The scores with the lowest value for ICU admission prediction were PSI with AUC of 0.620 (95% CI 0.549-0.690) and CURB-65 with AUC of 0.604 (95% CI 0.528-0.680)., Conclusions: Prognosis scores routinely used for CAP (PSI and CURB-65) were good predictors for mortality in patients with Covid-19 CAP but not for need of hospitalisation or ICU admission. In the evaluation of Covid-19 pneumonia, we need scores that allow to decide the appropriate level of care., (© 2020 John Wiley & Sons Ltd.)

The Clearum dialyzer, built by Medtronic, became commercially available in several European countries in 2020, but there are still no reports of in vivo data. The aim of this study was to evaluate the efficacy and risk of hypoalbuminemia of this dialyzer compared with previously evaluated hemodialysis (HD), expanded hemodialysis (HDx), and postdilution hemodiafiltration (HDF) treatments. A prospective study was carried out in 15 patients. Each patient underwent seven dialysis sessions: FX80 Cordiax in HD, Clearum HS17 in HD, Phylther 17-SD in HDx, Theranova 400 in HDx, Phylther 17-G in postdilution HDF, Clearum HS17 in postdilution HDF, and FX80 Cordiax in postdilution HDF. The reduction ratios of urea, creatinine, ß 2 -microglobulin, myoglobin, prolactin, α 1 -microglobulin, α 1 -acid glycoprotein, and albumin were compared intraindividually. Dialysate albumin loss was also measured. Comparison of dialysis techniques revealed no differences between small molecules, but HDx and HDF were significantly higher than HD with medium and large molecular weights. The Clearum dialyzer in HDF obtained similar results to FX80 Cordiax in HDF, was slightly superior to Phylther 17-G in HDF, and was statistically superior to both dialyzers in HDx. Albumin losses with the Clearum dialyzer were among the lowest, both in HD and HDF treatments. The highest global removal score (GRS) values were obtained with the helixone and Clearum dialyzers in HDF, with similar results both in HD and HDF. In addition, the GRS values with HDx treatments were statistically significantly higher than those with HD. The new Clearum dialyzer has excellent behavior and tolerance in HD and HDF. Its adequate permeability has been proven with its maximal performance in HDF, which could represent an upgrade versus its predecessor polyphenylene dialyzers., (© 2021 The Authors. Artificial Organs published by International Center for Artificial Organ and Transplantation (ICAOT) and Wiley Periodicals LLC.)

Introduction: Patients undergoing hemodialysis (HD) are characterized by a poor physical condition and a substantial sedentary profile. The implementation of physical exercise programs in the hemodialysis units is usually limited by the inherent safeness and the lack of appropriate resources., Objectives: We aimed to evaluate the impact and safety outcomes of the implementation of an intradialytic physical exercise program (IPE) by a multidisciplinary team (physiotherapist and nursing assistant) in the physical condition of the patients., Material and Methods: This six months single-centre and experimental pre-post prospective study was carried out in 34 patients. A two day-week combined IPE intervention was implemented. The cardiopulmonary capacity (6MWT), muscular strength (HG, leg dynamometry and 10STS), body composition (bioimpedance) and coordination capacity (Timed Up and Go test) was assessed at the beginning and at the end of the study. Safety was evaluated by means of the number of issues regarding the vascular access, the hemodynamic stability as well as the vascular refilling profile (RBV) in each session. The adhesion to the program was also registered. Additionally, analytical parameters were recorded., Results: The adhesion to an IPE program was high (70.8%). A significant improvement of the cardiopulmonary capacity (6MWT average increase 47 m; p < 0.001), superior limbs (HG average increase of 1.6 kg; p = 0.007) as well as the lower extremities (10STS; p = 0.003; dynamometry p < 0.05). Regarding safeness, there were no incidences neither significant difference in the RBV., Conclusions: A combined IPE may contribute to the improvement of the physical condition of the patients as well as ensures a safe development of the HD treatment. We suggest a multidisciplinary team in order to efficiently establish an IPE program., (Copyright © 2021 Sociedad Española de Nefrología. Published by Elsevier España, S.L.U. All rights reserved.)

Toray has created a new generation of dialyzers, the polysulphone (TS) UL series, and polymethylmethacrylate (PMMA) NF-U series, which offer enhanced efficacy over the previous TS-S series and NF-H series. The aim of this study was to evaluate the safety and efficacy of these dialyzer series versus contrasted expanded hemodialysis (HDx) and postdilution hemodiafiltration (HDF). We conducted a prospective study in 12 patients. Each patient underwent six dialysis sessions: FX80 Cordiax in HD, Toraysulfone TS-1.8 UL in HD, Theranova 400 in HDx, polymethylmethacrylate (PMMA) NF-2.1 U in HDF, Toraysulfone TS-2.1 UL in HDF, and FX80 Cordiax in HDF. The removal ratios (RRs) of urea, creatinine, ß 2 -microglobulin, myoglobin, prolactin, α 1 -microglobulin, α 1 -acid glycoprotein, and albumin were compared intraindividually. Dialysate albumin loss was also measured. The RRs for β 2 -microglobulin, myoglobin, prolactin, α 1 -microglobulin, and α 1 -acid glycoprotein were higher with the TS-2.1 UL and FX80 Cordiax dialyzers in HDF than those obtained with HD treatments and NF-2.1 U in HDF. The β 2 -microglobulin, myoglobin, and prolactin RRs were also higher with HDx than those obtained with HD treatments. The myoglobin and prolactin RRs were higher with TS-1.8 UL in HD than those obtained with helixone dialyzers in HD. Dialysate albumin loss was less than 3 g in all situations except in TS-2.1 UL in HDF. The highest global removal score values were obtained with the TS-2.1 UL and helixone dialyzers in HDF. Significant differences were found between all study situations. In conclusion, the new generation dialyzers, Toraysulfone TS Series UL and PMMA NF-U series, show excellent behaviour and tolerance in HD and HDF, representing an upgrade versus their predecessor series. The higher permeability of the TS UL series has been proven with higher efficiency in HD and maximum performance in HDF. The new PMMA NF-U series allows the use of HDF with good efficiency and complete safety., (© 2021 International Center for Artificial Organs and Transplantation and Wiley Periodicals LLC.)

Background: Cardiogenic pulmonary oedema (CPE) may contribute to ventilator-associated lung injury (VALI) in patients with cardiogenic shock. The appropriate ventilatory strategy remains unclear. We aimed to evaluate the impact of ultra-low tidal volume ventilation with tidal volume of 3 ml/kg predicted body weight (PBW) in patients with CPE and veno-arterial extracorporeal membrane oxygenation (V-A ECMO) on lung inflammation compared to conventional ventilation., Methods: A single-centre randomized crossover trial was performed in the Cardiac Intensive Care Unit (ICU) at a tertiary university hospital. Seventeen adults requiring V-A ECMO and mechanical ventilation due to cardiogenic shock were included from February 2017 to December 2018. Patients were ventilated for two consecutive periods of 24 h with tidal volumes of 6 and 3 ml/kg of PBW, respectively, applied in random order. Primary outcome was the change in proinflammatory mediators in bronchoalveolar lavage fluid (BALF) between both ventilatory strategies., Results: Ventilation with 3 ml/kg PBW yielded lower driving pressures and end-expiratory lung volumes. Overall, there were no differences in BALF cytokines. Post hoc analyses revealed that patients with high baseline levels of IL-6 showed statistically significant lower levels of IL-6 and IL-8 during ultra-low tidal volume ventilation. This reduction was significantly proportional to the decrease in driving pressure. In contrast, those with lower IL-6 baseline levels showed a significant increase in these biomarkers., Conclusions: Ultra-low tidal volume ventilation in patients with CPE and V-A ECMO may attenuate inflammation in selected cases. VALI may be driven by an interaction between the individual proinflammatory profile and the mechanical load overimposed by the ventilator. Trial registration The trial was registered in ClinicalTrials.gov (identifier NCT03041428, Registration date: 2nd February 2017)., (© 2021. The Author(s).)

Expanded CD4+CD28 null T lymphocytes are found in the tissues and peripheral blood of patients with many autoimmune diseases, such as rheumatoid arthritis (RA). These highly differentiated cells present potent inflammatory activity and capability to induce tissue destruction, which has been suggested to predispose to the development of more aggressive disease. In fact, preferential migration to inflammatory sites has been proposed to be a contributing factor in the progression of autoimmune and cardiovascular diseases frequently found in these patients. The functional activity of CD4+CD28 null T lymphocytes is largely dependent on interleukin 15 (IL-15), and this cytokine may also act as a selective attractor of these cells to local inflammatory infiltrates in damaged tissues. We have analysed, in RA patients, the migratory properties and transcriptional motility profile of CD4+CD28 null T lymphocytes compared to their counterparts CD28+ T lymphocytes and the enhancing role of IL-15. Identification of the pathways involved in this process will allow us to design strategies directed to block effector functions that CD4+CD28 null T lymphocytes have in the target tissue, which may represent therapeutic approaches in this immune disorder.

Adsorption properties of hemodialyzers are traditionally retrieved from diffusive treatments and mainly focused on inflammatory markers and plasma proteins. The possible depurative enhancement of middle and high molecular weight solutes, as well as protein-bound uremic toxins by adsorption in convective treatments, is not yet reported. We used discarded plasma exchanges from uremic patients and out-of-date erythrocytes as a novel in vitro uremic precursor matrix to assess removal and adsorption patterns of distinct material and structure but similar surface hemodialyzers in hemodialysis and on-line hemodiafiltration treatments. We further related the obtained results to the possible underlying membrane pore blocking mechanisms. Convection improved removal but slightly enhanced adsorption in the cellulosic and synthetic dialyzers tested. The polymethylmethacrylate hemodialyzer obtained the highest extracted ([Formula: see text]) and adsorbed ([Formula: see text]) mass values when submitted to hemodiafiltration for all molecules analyzed including albumin ([Formula: see text] g, [Formula: see text] mg), whereas the polyamide membrane obtained substantial lower results even for this molecule ([Formula: see text] g, [Formula: see text] mg) under the same treatment parameters. Hemodiafiltration in symmetric and enlarged pore hemodialyzers enhances removal and adsorption by internal pore deposition (intermediate pore-blocking) for middle and high molecular weight toxins but leads to substantial and deleterious albumin depuration.

The aim of the study was to compare expanded hemodialysis (HDx) with hemodiafiltration (HDF) at different infusion flows to identify the main determinants, namely blood flow (Qb), replacement volume, infusion flow (Qi), ultrafiltration flow (Q uf ), filtration fraction (FF), and the point at which the effectiveness of HDF equals or exceeds that of HDx. We conducted a prospective, single-center study in 12 patients. Each patient underwent 12 dialysis sessions: six sessions with Qb 350 and six with Qb 400 mL/min; with each Qb, one session was with HDx and five sessions were with FX80 (one in HD, and four with Qi 50, 75, 90/100 mL/min or autosubstitution in postdilution HDF). The reduction ratios (RR) of urea, creatinine, ß 2 -microglobulin, myoglobin, prolactin, α 1 -microglobulin, α 1 -acid glycoprotein, and albumin were compared intraindividually and the global removal score (GRS) was calculated. The mean replacement volume with Qb 350 mL/min was 13.77 ± 0.92 L with Qi 50 mL/min, 20.75 ± 1.17 L with Qi 75, 23.83 ± 1.92 L with Qi 90, and 27.51 ± 2.77 L with autosubstitution. Similar results were obtained with Qb 400 mL/min, and the results were only slightly higher with Qi 100 mL/min or in autosubstitution. The GRS was positively correlated with replacement volume with Qb 350 (R 2  = 0.583) and with Qb 400 (R 2  = 0.584); with Q uf with Qb 350 (R 2  = 0.556) and with Qb 400 (R 2  = 0.604); and also with FF with Qb 350 (R 2  = 0.556) and with Qb 400 mL/min (R 2  = 0.603). The minimum convective volume in HDF from which it is possible to overcome the efficacy of HDx was 19.2 L with Qb 350 and 17.6 L with Qb 400 mL/min. The cut-off point of Q uf at which HDF exceeded the effectiveness of HDx was 80.6 mL/min with Qb 350 and 74.1 mL/min with Qb 400 mL/min. The cut-off point at which FF in HDF exceeded the effectiveness of the HDx was 23.0% with Qb 350 and 18.6% with Qb 400 mL/min. In conclusion, this study confirms the superiority of postdilution HDF over HDx when replacement volume, convective volume, Q uf , or FF exceeds certain values. Increasing the Qb in postdilution HDF manages to increase the convective dose and more easily overcome the HDx., (© 2020 International Center for Artificial Organs and Transplantation and Wiley Periodicals, Inc.)

Blood flow (Qb) is one of the dialysis parameters most strongly influencing the performance of dialysis modalities. However, few studies have compared different dialysis modalities in patients with low Qb. We conducted a prospective, single-center study in 21 patients. Each patient underwent four dialysis sessions with routine dialysis parameters: high-flux hemodialysis (HD), predilution hemodiafiltration (pre-HDF), expanded HD (HDx), and postdilution HDF (post-HDF). The removal ratios (RR) of urea, creatinine, ß 2 -microglobulin, myoglobin, prolactin, α 1 -microglobulin, free kappa and lambda immunoglobulin light chains (ķFLC and λFLC), α 1 -acid glycoprotein, and albumin were compared intraindividually. A proportional part of the dialysate was collected to quantify albumin loss. There were no differences in urea and creatinine RRs. The β 2 -microglobulin RR was higher in pre-HDF and post-HDF. Myoglobin and prolactin RRs were higher with HDx and post-HDF. The α 1 -microglobulin and α 1 -acid glycoprotein RRs were significantly higher with post-HDF than with other treatments, and RRs obtained with HDx were higher than obtained with HD and pre-HDF. Free ķFLC and λFLC RRs showed the following results in ascending order: HD, pre-HDF, HDx, and post-HDF, most of them with statistical significance. Albumin loss varied from 0.45 g with HD to 3.5 g with post-HDF. The global removal score values were 41.0 ± 4.8% with HD, 44.0 ± 5.2% with pre-HDF, 49.5 ± 4.6% with HDx, and 54.8 ± 5.3% with post-HDF, with significant differences between all treatment modalities. In conclusion, this study confirms the superiority of post-HDF over high-flux HD, pre-HDF, and HDx in patients with low Qb. HDx was the closest alternative to post-HDF and was clearly superior to HD and pre-HDF. Finally, pre-HDF was also superior to HD. With this Qb, there was a higher risk of underdialysis, both diffusive and convective, especially in patients with a session duration of less than 5 h., (© 2019 International Society for Apheresis, Japanese Society for Apheresis, and Japanese Society for Dialysis Therapy.)

Background: Metabolic acidosis is a common problem in haemodialysis patients, but acidosis overcorrection has been associated with higher mortality. There is no clear definition of the optimal serum bicarbonate target or dialysate bicarbonate. This study analysed the impact of reducing dialysate bicarbonate from 35 to 32 mEq/L on plasma bicarbonate levels in a cohort of patients treated with online haemodiafiltration (OL-HDF)., Methods: We performed a prospective cohort study with patients in a stable chronic OL-HDF programme for at least 12 months in the Hospital Clinic of Barcelona. We analysed pre- and post-dialysis total carbon dioxide(TCO 2) before and after dialysate bicarbonate reduction from 35 to 32 mEq/L, as well as the number of patients with a pre- and post-dialysis TCO 2 within 19-25 and ≤29 mEq/L, respectively, after the bicarbonate modification. Changes in serum sodium, potassium, calcium, phosphorous and parathyroid hormone (PTH) were also assessed., Results: We included 84 patients with a 6-month follow-up. At 6 months, pre- and post-dialysis TCO 2 significantly decreased (26.78 ± 1.26 at baseline to 23.69 ± 1.92 mEq/L and 31.91 ± 0.91 to 27.58 ± 1.36 mEq/L, respectively). The number of patients with a pre-dialysis TCO 2 >25 mEq/L was significantly reduced from 80 (90.5%) to 17 (20.2%) and for post-dialysis TCO 2  >29 mEq/L this number was reduced from 83 (98.8%) to 9 (10.7%). PTH significantly decreased from 226.09 (range 172-296) to 182.50 (125-239)  pg/mL at 6 months (P   <   0.05) and post-dialysis potassium decreased from 3.16 ± 0.30 to 2.95 ± 0.48 mEq/L at 6 months (P   <   0.05). Sodium, pre-dialysis potassium, calcium and phosphorous did not change significantly., Conclusions: Reducing dialysate bicarbonate concentration by 3 mEq/L significantly and safely decreased pre- and post-dialysis TCO 2 , avoiding acidosis overcorrection and improving secondary hyperparathyroidism control. An individualized bicarbonate prescription (a key factor in the adequate control of acidosis) according to pre-dialysis TCO 2 is suggested based on these results., (© The Author(s) 2020. Published by Oxford University Press on behalf of ERA-EDTA.)

Objective: The aim of our study was to determine the tomographic findings and prevalence of bronchiectasis in our population of patients with severe asthma, and to identify factors associated with the presence of bronchiectasis in these patients. Materials and methods: We retrospectively collected data from the medical histories of patients referred to the asthma unit of our hospital, with a diagnosis of severe asthma between 2015 and 2017. Patients with ABPA, cystic fibrosis, immunodeficiency or systemic disease were excluded. High-resolution thorax-computed tomodensitography (HRCT) was performed in all patients. A standardized protocol was applied in data collection. Results: A total of 108 patients comprising 50 men (46%) and 58 women (54%) were included in the study. Of the 108 patients, 59 (55%) had at least one abnormality detected by HRCT, the most commonly reported abnormalities being bronchiectasis (35%), bronchial wall thickening (33%), emphysema (7%), atelectasis area (6%), mosaic attenuation due to air trapping (4%), and "tree in bud" image (2%). Subjects with bronchiectasis were older ( p = 0.001), had a longer asthma history ( p = 0.048), had poorer pulmonary function tests with lower FVC ( p = 0.031), had more severe bronchial obstruction with lower FEV1 ( p = 0.008) and had lower FEV1/FVC ( p = 0.003). They also experienced more frequent hospitalizations in the previous year ( p = 0.019) and received treatment with omalizumab more frequently ( p = 0.049). Plasma eosinophil count and IgE levels were comparable in both groups. In the multivariate analysis, the presence of bronchiectasis was associated with ages older than 40 (OR: 8.3; 95% CI: 1.7-41.2) and chronic airflow obstruction (OR: 5.4; 95% CI: 1.9-15.3). Conclusions: We found that in patients with severe asthma, the prevalence of bronchiectasis is high and that bronchiectasis is associated with a longer asthma history, greater severity and, more importantly, chronic airflow obstruction. These findings are still insufficient evidence to considere features of asthma-bronchiectasis overlap syndrome, a distinct phenotype of severe asthma, but bronchiectasis is a frequent phenomenon leading to a more severe disease with frequent exacerbations. The performance of thorax HRCT on patients with severe asthma can help to evaluate management strategies for the disease in order to improve treatment and prognosis.