Acute kidney injury in patients with COVID-19: a retrospective cohort study from Switzerland.

BACKGROUND: Data about patients in Europe with corona virus disease-2019 (COVID-19) and acute kidney injury (AKI) are scarce. We examined characteristics, presentation and risk factors of AKI in patients hospitalised with COVID-19 in a tertiary hospital in Switzerland. METHODS: We reviewed health records of patients hospitalised with a positive nasopharyngeal polymerase chain reaction test for SARS-CoV2 between 1 February and 30 June 2020, at the University Hospital of Basel. The nadir creatinine of the hospitalisation was used as baseline. AKI was defined according the KDIGO guidelines as a 1.5× increase of baseline creatinine and in-hospital renal recovery as a discharge creatinine <1.25× baseline creatinine. Least absolute shrinkage and selection operator (LASSO) regression was performed to select predictive variables of AKI. Based on this a final model was chosen. RESULTS: Of 188 patients with COVID-19, 41 (22%) developed AKI, and 11 (6%) required renal replacement therapy. AKI developed after a median of 9 days (interquartile range [IQR] 5-12) after the first symptoms and a median of 1 day (IQR 0-5) after hospital admission. The peak AKI stages were stage 1 in 39%, stage 2 in 24% and stage 3 in 37%. A total of 29 (15%) patients were admitted to the intensive care unit and of these 23 (79%) developed AKI. In-hospital renal recovery at discharge was observed in 61% of all AKI episodes. In-hospital mortality was 27% in patients with AKI and 10% in patients without AKI. Age (adjusted odds ratio [aOR] 1.04, 95% confidence interval [CI] 1.01­1.08; p = 0.024), history of chronic kidney disease (aOR 3.47, 95% CI 1.16­10.49;p = 0.026), C-reactive protein levels (aOR 1.09, 95% CI 1.03­1.06; p = 0.002) and creatinine kinase (aOR 1.03, 95% CI 1.01­1.06; p = 0.002) were associated with development of AKI. CONCLUSIONS: AKI is common in hospitalised patients with COVID-19 and more often seen in patients with severe COVID-19 illness. AKI is associated with a high in-hospital mortality.

Incidence of new onset glomerulonephritis after SARS-CoV-2 mRNA vaccination is not increased.

Numerous cases of glomerulonephritis manifesting shortly after SARS-CoV-2 vaccination have been reported, but causality remains unproven. Here, we studied the association between mRNA-based SARS-CoV-2 vaccination and new-onset glomerulonephritis using a nationwide retrospective cohort and a case-cohort design. Data from all Swiss pathology institutes processing native kidney biopsies served to calculate incidence of IgA nephropathy, pauci-immune necrotizing glomerulonephritis, minimal change disease, and membranous nephropathy in the adult Swiss population. The observed incidence during the vaccination campaign (January to August 2021) was not different from the expected incidence calculated using a Bayesian model based on the years 2015 to 2019 (incidence rate ratio 0.86, 95% credible interval 0.73-1.02) and did not cross the upper boundary of the 95% credible interval for any month. Among 111 patients 18 years and older with newly diagnosed glomerulonephritis between January and August 2021, 38.7% had received at least one vaccine dose before biopsy, compared to 39.5% of the general Swiss population matched for age and calendar-time. The estimated risk ratio for the development of new-onset biopsy-proven glomerulonephritis was not significant at 0.97 (95% confidence interval 0.66-1.42) in vaccinated vs. unvaccinated individuals. Patients with glomerulonephritis manifesting within four weeks after vaccination did not differ clinically from those manifesting temporally unrelated to vaccination. Thus, vaccination against SARS-CoV-2 was not associated with new-onset glomerulonephritis in these two complementary studies with most temporal associations between SARS-CoV-2 vaccination and glomerulonephritis likely coincidental.

Mimics and chameleons of COVID-19: patient presentation and accuracy of triage during the first wave.

STUDY AIMS: To quantify mimics and chameleons of coronavirus disease 2019 (COVID-19), to analyse the diagnostic accuracy of the triage protocol, and to describe the resulting groups of mimics and chameleons - including their presenting symptoms and final diagnoses. METHODS: Diagnostic accuracy study including all adult patients tested for severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2) at the emergency department of the University Hospital Basel, Switzerland during the first wave of pandemic in spring 2020. Diagnostic accuracy of triage was determined by calculating sensitivity, specificity, positive and negative predictive value, and positive and negative likelihood ratio. Triage to the group of suspected (+) and not suspected (-) COVID-19 was considered the index test, whereas a SARS-CoV-2 polymerase chain reaction test result was used as reference standard. Mimics were defined as false positives and chameleons as false negatives. RESULTS: Of 2898 patients included in the analysis, 191 were true positives, 895 were false positives (mimics), 9 were false negatives (chameleons) and 1803 were true negatives. This resulted in a sensitivity of 0.95 (95% confidence interval [CI] 0.92-0.98) and a specificity of 0.67 (95% CI 0.65-0.69) for standardised triage. Among mimics, the main categories of final diagnoses were other infections (n = 513, 57.3%), cardiovascular diseases (excluding cerebrovascular) (n = 125, 14%), and non-infectious diseases of the respiratory system (n = 84, 9.4%). Fever (n = 357, 39.9% vs n = 104, 54.5%), cough (n = 466, 52.1% vs n = 126 66%), and smell or taste dysfunction (n = 60, 6.7% vs n = 24, 12.6%) were less frequently observed in mimics than in COVID-19 patients. Eight of nine COVID-19 chameleons presented with either nonspecific complaints (weakness and/or fatigue) or gastrointestinal symptoms. CONCLUSION: The quantitative assessment of COVID-19 mimics and chameleons showed a high prevalence of mimics. Clinical differentiation between true positives and false positives is not feasible due to largely overlapping symptoms. Prevalence of chameleons was very low.

Temporal trends of COVID-19 related in-hospital mortality and demographics in Switzerland - a retrospective single centre cohort study.

AIMS: The aim of this study was to analyse the demographics, risk factors and in-hospital mortality rates of patients admitted with coronavirus disease 2019 (COVID-19) to a tertiary care hospital in Switzerland. METHODS: In this single-centre retrospective cohort study at the University Hospital Basel, we included all patients with confirmed severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection hospitalised from 27 February 2020 to 10 May 2021. Patients’ characteristics were extracted from the electronic medical record system. The primary outcome of this study was temporal trends of COVID-19-related in-hospital mortality. Secondary outcomes were COVID-19-related mortality in patients hospitalised on the intensive care unit (ICU), admission to ICU, renal replacement therapy and length of hospital stay, as well as a descriptive analysis of risk factors for in-hospital mortality. RESULTS: During the study period we included 943 hospitalisations of 930 patients. The median age was 65 years (interquartile range [IQR] 53–76) and 63% were men. The numbers of elderly patients, patients with multiple comorbidities and need for renal replacement therapy decreased from the first and second to the third wave. The median length of stay and need for ICU admission were similar in all waves. Throughout the study period 88 patients (9.3%) died during the hospital stay. Crude in-hospital mortality was similar over the course of the first two waves (9.5% and 10.2%, respectively), whereas it decreased in the third wave (5.4%). Overall mortality in patients without comorbidities was low at 1.6%, but it increased in patients with any comorbidity to 12.6%. Predictors of all-cause mortality over the whole period were age (adjusted odds ratio [aOR] per 10-year increase 1.81, 95% confidence interval [CI] 1.45–2.26; p <0.001), male sex (aOR 1.68, 95% CI 1.00–2.82; p = 0.048), immunocompromising condition (aOR 2.09, 95% CI 1.01–4.33; p = 0.048) and chronic kidney disease (aOR 2.25, 95% CI 1.35–3.76; p = 0.002). CONCLUSION: In our study in-hospital mortality was 9.5%, 10.2% and 5.4% in the first, second and third waves, respectively. Age, immunocompromising condition, male sex and chronic kidney disease were factors associated with in-hospital mortality. Importantly, patients without any comorbidity had a very low in-hospital mortality regardless of age.

Comparison of Acute Kidney Injury in Patients with COVID-19 and Other Respiratory Infections: A Prospective Cohort Study.

Previous studies have indicated an association between coronavirus disease 2019 (COVID-19) and acute kidney injury (AKI) but lacked a control group. The prospective observational COronaVIrus-surviVAl (COVIVA) study performed at the University Hospital, Basel, Switzerland consecutively enrolled patients with symptoms suggestive of COVID-19. We compared patients who tested positive for SARS-CoV-2 with patients who tested negative but with an adjudicated diagnosis of a respiratory tract infection, including pneumonia. The primary outcome measure was death at 30 days, and the secondary outcomes were AKI incidence and a composite endpoint of death, intensive care treatment or rehospitalization at 30 days. Five hundred and seven patients were diagnosed with respiratory tract infections, and of those, 183 (36%) had a positive PCR swab test for SARS-CoV-2. The incidence of AKI was higher in patients with COVID-19 (30% versus 12%, p < 0.001), more severe (KDIGO stage 3, 22% versus 13%, p = 0.009) and more often required renal replacement therapy (4.4% versus 0.93%; p = 0.03). The risk of 30-day mortality and a composite endpoint was higher in patients with COVID-19-associated AKI (adjusted hazard ratio (aHR) mortality 3.98, 95% confidence interval (CI) 1.10-14.46, p = 0.036; composite endpoint aHR 1.84, 95% CI 1.02-3.31, p = 0.042). The mortality risk was attenuated when adjusting for disease severity (aHR 3.60, 95% CI 0.93-13.96, p = 0.062). AKI occurs more frequently and with a higher severity in patients with COVID-19 and is associated with worse outcomes.