Systemic sclerosis (SSc) is a complex rheumatologic autoimmune disease in which inflammation, fibrosis, and vasculopathy share several pathogenic pathways that lead to skin and internal organ damage. Recent findings regarding the participation and interaction of the innate and acquired immune system have led to a better understanding of the pathogenesis of the disease and to the identification of new therapeutic targets, many of which have been tested in preclinical and clinical trials with varying results. In this manuscript, we review the state of the art of the pathogenesis of this disease and discuss the main therapeutic targets related to each pathogenic mechanism that have been discovered so far.

Introduction: Expanded hemodialysis (HDx) is expected to provide enhanced permeability of medium-sized molecules, selective solute retention, and better internal retrofiltration. The primary objective of this study was to compare the efficiency for removal of β2-microglobulin with 3 different extracorporeal therapies (ETs): high-flux hemodialysis (HF), online hemodiafiltration (OL-HDF), and HDx. The secondary objective was to evaluate the efficiency of removal of other uremic toxins, including urea, phosphate, CRP, IL-6, IL-10, TNF-⍺, indoxyl sulfate, and p-cresol. Methods: This single-center, randomized, and cross-over study was performed. Patients were randomized to determine the initial modality of treatment, each period lasted 4 weeks and between one modality and another, there was a washout period of 1 week. Reduction ratios (RRs) of different-size molecules and albumin were calculated for the different ET. Results: Twenty-two patients were included, β2-microglobulin RR was greater during both OL-HDF and HDx as compared to HF (RR 62% vs. 73% vs. 27%, respectively, p = <0.0001), and there was no significant difference between HDx and OL-HDF (p = 0.09). A decrease in serum phosphate levels was observed in the HDx and OL-HDF periods, contrary to an increase in HF (−0.79 mg/dL vs. −1.02 mg/dL vs. + 0.11 mg/dL, respectively, p = <0.0001). There was no difference in RRs of other molecules (BUN, CRP, IL-6, IL-10, TNF-⍺, indoxyl sulfate, and p-Cresol). There was no decrease in serum albumin in any ET. Conclusion: HDx provides enhanced removal of β2-microglobulin and phosphate as compared to HF, and similar efficacy as with OL-HDF. HDx should be considered an alternative to chronic convective therapies.

Initial reports suggested that kidney involvement after coronavirus disease 19 (COVID-19) infection was uncommon, but this premise appears to be incorrect. Acute kidney injury can occur through various mechanisms and complicate the course of up to 25% of patients with COVID-19 hospitalized in our Institution, and of over 50% of those on invasive mechanical ventilation. Mechanisms of injury include direct kidney injury and predominantly tubular, although glomerular injury has been reported, and resulting from severe hypoxic respiratory failure, secondary infection, and exposure to nephrotoxic drugs. The mainstay of treatment remains the prevention of progressive kidney damage and, in some cases, the use of renal replacement therapy. Although the use of blood purification techniques has been proposed as a potential treatment, results to date have not been conclusive. In this manuscript, the mechanisms of kidney injury by COVID-19, risk factors, and the mainstays of treatment are reviewed.

Background: Major adverse kidney events (MAKEs), including death, persistent AKI (pAKI), and renal replacement therapy, are more common in SARS-CoV-2-related ARDS. Invasive mechanical ventilation (IMV), systemic inflammation, and hemodynamic changes drive this risk. This study examines early IMV settings and urinary kidney biomarkers (UKBs) to better understand the development of MAKEs at 30 days. Methods: This prospective, cross-sectional cohort study was conducted in a single center between September and October 2021. This study included adults (≥18 years) diagnosed with ARDS due to SARS-CoV-2, requiring IMV within the first 6 h of admission. Exclusion criteria included a history of chronic kidney disease (CKD) and pregnant women. Initial mechanical ventilator settings were recorded after compliance-guided PEEP titration, and urine samples were collected for the analysis of UKBs at the same time. Our primary and secondary endpoints were to assess risk factors associated with MAKEs at 30 days and pAKI, respectively. Results: The cohort included 45 patients, with a median age of 57.75 (±18.64) years. In total, 32 (71%) developed MAKEs and 22 (48.8%) developed pAKI. MAKEs were associated with older age (adjusted odds ratio (aORs) = 1.23 95% CI: 1.00–1.22; p = 0.038) and higher driving pressure (ΔP) (aORs = 1.62, 95% CI:1.01–2.60, p = 0.043). Only urinary neutrophil gelatinase-associated lipocalin (uNGal) > 40 ng/mL was associated with pAKI (aORs = 8.54, 95% CI:1.75–41.65, p = 0.008). Conclusions: Early ventilator settings, particularly higher ΔP, play a critical role in the development of MAKEs. uN-Gal could enhance the early detection of pAKI, providing opportunities for timely interventions.