At the beginning of 2020, the outbreak of coronavirus disease 2019 (COVID-19) led to a worldwide pandemic and mass panic. The number of infected people has been increasing exponentially since, and the mortality rate has also been concomitantly increasing. At present, no study has summarized the mortality risk of COVID-19 in patients with chronic kidney disease (CKD). Therefore, the aim of the present study was to conduct a literature review and meta-analysis to understand the frequency of mortality among CKD patients infected with COVID-19. A comprehensive systematic search was conducted on the PubMed, Embase, and Cochrane databases to find articles published until May 15, 2020. Study quality was assessed using a modified version of the Newcastle–Ottawa Scale. After careful screening based on the inclusion and exclusion criteria, 3,867,367 patients from 12 studies were included. The mortality rate was significantly higher among CKD patients with COVID-19 infection than among CKD patients without COVID-19 infection, as indicated by a pooled OR of 5.81 (95% CI 3.78–8.94, P < 0.00001, I2 = 30%). The patients were then stratified into ≥ 70 and < 70 years, and subgroup analysis revealed that among CKD patients with COVID-19 infection, the mortality rate was higher in the < 70 years group (OR 8.69, 95% CI 7.56–9.97, P < 0.0001) than in the ≥ 70 years group (OR 2.44, 95% CI 0.75–6.63, P = 0.15). Thus, COVID-19 patients with CKD have a high mortality risk and require a comprehensive multidisciplinary management strategy.

Objectives The impact of rheumatic diseases on COVID-19 infection remains poorly investigated. Here we performed a systematic review and meta-analysis to evaluate the outcomes of COVID-19 in patients with rheumatic diseases. Methods We systematically searched PubMed, Embase, Cochrane Library, Scopus and preprint database up to 29th August 2020, for publications with confirmed COVID-19 infection in patients with rheumatic diseases. The primary outcomes were the rates of hospitalization, oxygen support, intensive care unit (ICU) admission and death. A meta-analysis of effect sizes using the random-effects models was performed, and meta-regression analyses were performed to explore heterogeneity. The data from the COVID-19 Global Rheumatology Alliance physician registry (the COVID-19 GRA) was used as a reference. Results A total of 31 articles involving 1138 patients were included in this systematic review and meta-analysis. The publications were from Europe, Asia and North America, but none from other continents. The overall rates of hospitalization, oxygen support, ICU admission and fatality among COVID-19 infected patients with rheumatic diseases were 0.58 (95% confidence interval (CI) 0.48–0.67), 0.33 (95% CI 0.21–0.47), 0.09 (95% CI 0.05–0.15) and 0.07 (95% CI 0.03–0.11), respectively. The rate of oxygen support in Europe (0.48, 95% CI 0.4–0.57) was higher than that in other continents. Among all hospitalized patients, the rates of oxygen support, ICU admission and fatality were 0.61 (95% CI 0.48–0.73), 0.13 (95% CI 0.07–0.21) and 0.13 (95% CI 0.09–0.18), respectively. The fatality rate was highest in Europe (0.19, 95% CI 0.15–0.24). The fatality rate was higher both in this meta-analysis and the COVID-19 GRA (7.0% and 6.7%, respectively) than that (3.4%) in WHO database, although the age, gender and comorbidity were not matched. Conclusion Patients with rheumatic diseases remain vulnerable with substantial rates of severe outcomes and a geographic variation. More studies were urgently needed to elucidate the risk factors of severe outcomes in this population.

Background. Idiopathic membranous nephropathy (IMN) is a major cause of adult nephrotic syndromes, and reliable noninvasive biomarkers for diagnosis and monitoring are urgently needed. In this study, we performed small RNA (sRNA) sequencing to explore sRNA profiles of urinary exosomes derived from IMN patients and healthy controls (CON) to provide clues for identifying novel noninvasive sRNA biomarkers for IMN. Methods. Urine samples were collected from five healthy controls and six patients with IMN. High-throughput sequencing was used to screen sRNA expression profiles of urinary exosomes from patients with IMN in two independent cohorts. Results. Urinary exosomes were successfully isolated and used to obtain exosomal sRNAs. We screened 131 differentially expressed miRNAs, including 28 specifically expressed miRNAs, then explored the top 10 specifically expressed miRNAs in all IMN individuals. The specifically expressed miRNAs and differentially expressed miRNAs provide potential biomarkers for IMN. Additionally, we discovered numerous sRNAs derived from genomic repetitive sequences, which could represent an exciting new area of research. Conclusion. Herein, we revealed significant differences in expression profiles of urinary exosomal miRNAs and repetitive region-derived sRNAs between patients with IMN and healthy controls. The findings could facilitate the development of potential molecular targets for membranous nephropathy.