Long-term kidney function recovery and mortality after COVID-19-associated acute kidney injury: An international multi-centre observational cohort study

Impact on pulmonary, cardiac, and renal function and long-term quality of life after hospitalization for acute respiratory distress syndrome due to COVID-19: Protocol of the Post-COVID Brazil 3 study

RATIONALE

Evidence about long-term sequelae after hospitalization for acute respiratory distress syndrome due to COVID-19 is still scarce.

PURPOSE

To evaluate changes in pulmonary, cardiac, and renal function and in quality of life after hospitalization for acute respiratory distress syndrome secondary to COVID-19.

METHODS

This will be a multicenter case-control study of 220 participants. Eligible are patients who are hospitalized for acute respiratory distress syndrome due to COVID-19. In the control group, individuals with no history of hospitalization in the last 12 months or long-term symptoms of COVID-19 will be selected. All individuals will be subjected to pulmonary spirometry with a carbon monoxide diffusion test, chest tomography, cardiac and renal magnetic resonance imaging with gadolinium, ergospirometry, serum and urinary creatinine, total protein, and urinary microalbuminuria, in addition to quality-of-life questionnaires. Patients will be evaluated 12 months after hospital discharge, and controls will be evaluated within 90 days of inclusion in the study. For all the statistical analyses, p < 0.05 is the threshold for significance.

RESULTS

The primary outcome of the study will be the pulmonary diffusing capacity for carbon monoxide measured after 12 months. The other parameters of pulmonary, cardiac, and renal function and quality of life are secondary outcomes.

CONCLUSION

This study aims to determine the long-term sequelae of pulmonary, cardiac, and renal function and the quality of life of patients hospitalized for acute respiratory distress syndrome due to COVID-19 in the Brazilian population.

Clinical characteristics and outcomes of hospitalized kidney transplant recipients with COVID-19 infection in China during the Omicron wave: a single-center cohort study

BACKGROUND: Following the short-term outbreak of coronavirus disease 2019 (COVID-19) in December 2022 in China, clinical data on kidney transplant recipients (KTRs) with COVID-19 are lacking. METHODS: We conducted a single-center retrospective study to describe the clinical features, complications, and mortality rates of hospitalized KTRs infected with COVID-19 between Dec. 16, 2022 and Jan. 31, 2023. The patients were followed up until Mar. 31, 2023. RESULTS: A total of 324 KTRs with COVID-19 were included. The median age was 49 years. The median time between the onset of symptoms and admission was 13 d. Molnupiravir, azvudine, and nirmatrelvir/ritonavir were administered to 67 (20.7%), 11 (3.4%), and 148 (45.7%) patients, respectively. Twenty-nine (9.0%) patients were treated with more than one antiviral agent. Forty-eight (14.8%) patients were treated with tocilizumab and 53 (16.4%) patients received baricitinib therapy. The acute kidney injury (AKI) occurred in 81 (25.0%) patients and 39 (12.0%) patients were admitted to intensive care units. Fungal infections were observed in 55 (17.0%) patients. Fifty (15.4%) patients lost their graft. The 28-d mortality rate of patients was 9.0% and 42 (13.0%) patients died by the end of follow-up. Multivariate Cox regression analysis identified that cerebrovascular disease, AKI incidence, interleukin (IL)‍-6 level of >6.8 pg/mL, daily dose of corticosteroids of >50 mg, and fungal infection were all associated with an increased risk of death for hospitalized patients. CONCLUSIONS: Our findings demonstrate that hospitalized KTRs with COVID-19 are at high risk of mortality. The administration of immunomodulators or the late application of antiviral drugs does not improve patient survival, while higher doses of corticosteroids may increase the death risk.

New insights into kidney disease after COVID-19 infection and vaccination: histopathological and clinical findings

In addition to its pulmonary effects, coronavirus disease 2019 (COVID-19) has also been found to cause acute kidney injury (AKI), which has been linked to high mortality rates. In this review, we collected data from 20 clinical studies on post-COVID-19-related AKI and 97 cases of AKI associated with COVID-19 vaccination. Acute tubular injury was by far the most common finding in the kidneys of patients with COVID-19-related AKI. Among patients hospitalized for COVID-19, 34.0% developed AKI, of which 59.0%, 19.1% and 21.9% were Stages 1, 2 and 3, respectively. Though kidney disease and other adverse effects after COVID-19 vaccination overall appear rare, case reports have accumulated suggesting that COVID-19 vaccination may be associated with a risk of subsequent kidney disease. Among the patients with post-vaccination AKI, the most common pathologic findings include crescentic glomerulonephritis (29.9%), acute tubular injury (23.7%), IgA nephropathy (18.6%), antineutrophil cytoplasmic autoantibody-associated vasculitis (17.5%), minimal change disease (17.5%) and thrombotic microangiopathy (10.3%). It is important to note that crescentic glomerulonephritis appears to be more prevalent in patients who have newly diagnosed renal involvement. The proportions of patients with AKI Stages 1, 2 and 3 after COVID-19 vaccination in case reports were 30.9%, 22.7% and 46.4%, respectively. In general, clinical cases of new-onset and recurrent nephropathy with AKI after COVID-19 vaccination have a positive prognosis. In this article, we also explore the underlying pathophysiological mechanisms of AKI associated with COVID-19 infection and its vaccination by describing key renal morphological and clinical features and prognostic findings.

Are Kidneys Affected by SARS-CoV-2 Infection? An Updated Review on COVID-19-Associated AKI

BACKGROUND

Human kidneys are an important target of SARS-CoV-2 infection, and many renal abnormalities have been found in patients with SARS-CoV-2 infection, including proteinuria, hematuria, and acute kidney injury. Acute kidney injury is now considered a common complication of COVID-19, and the epidemiology of AKI in SARS-CoV-2-infected patients continues to be controversial.

AIM AND METHODS

We have carried out a narrative review to evaluate the frequency and risk factors for AKI among patients hospitalized due to COVID-19, and the latest surveys on this topic have been included. The mechanisms by which AKI occurs in COVID-19 patients have also been reviewed.

RESULTS

Multiple risk factors for the development of AKI in patients with SARS-CoV-2 infection have been identified; these have been classified in various groups (management and background factors, among others). SARS-CoV-2 targets the kidneys by indirect activity, but SARS-CoV-2 infects tubular epithelial cells and podocytes. We retrieved 24 reports (n = 502,593 unique patients with SARS-CoV-2 infection) and found an incidence of AKI of 31.8% (range, 0.5% to 56.9%). Only a minority (n = 2) of studies had a prospective design. We found that the AKI risk was greater in SARS-CoV-2 patients who underwent in-hospital deaths vs. those who survived; the summary estimate of the unadjusted RR of AKI was 2.63 (95% CI, 2.37; 2.93) (random-effects model). A stratified analysis showed that the incidence of AKI was greater in those reports where the frequency of COVID-19-positive patients having comorbidities (diabetes mellitus, arterial hypertension, and advanced age) was high. The unadjusted relative risk (aRR) of AKI was greater in SARS-CoV-2 patients who underwent ICU admission vs. those who did not; the pooled estimate of AKI risk was 2.64 (95% CI, 1.96; 3.56) according to the random-effects model.

CONCLUSIONS

AKI is a common complication of hospitalized SARS-CoV-2-infected patients, and some comorbidities are important risk factors for it. The direct activity of the virus on the kidneys has been mentioned in the pathogenesis of AKI in SARS-CoV-2 patients. Further studies are ongoing in order to identify the mechanisms underlying the kidney injury in this population. The role of AKI on survival in SARS-CoV-2-infected patients is another area of active investigation.

COVID-19-Associated Acute Kidney Injury and Longitudinal Kidney Outcomes

Importance

COVID-19 infection is associated with a high incidence of acute kidney injury (AKI). Although rapid kidney function decline has been reported in the first few months after COVID-19-associated AKI (COVID-AKI), the longer-term association of COVID-AKI with kidney function remains unknown.

Objective

To assess long-term kidney outcomes of patients who had COVID-19-associated AKI.

Design, Setting, and Participants

This was a retrospective longitudinal multicenter cohort study conducted in a large hospital system using electronic health records data on adult hospitalized patients with AKI and COVID-19 or other illnesses. Included patients were hospitalized during the COVID-19 pandemic (March 2020-June 2022), were screened for SARS-CoV-2, had AKI, and survived to discharge, or had been hospitalized during the 5 years before the pandemic (October 2016-January 2020), had a positive influenza A or B test result, had AKI, and survived to discharge. Patients were followed up for a maximum of 2 years after hospital discharge. Data analyses were performed from December 2022 to November 2023.

Exposure

COVID-19 and influenza.

Main Outcomes and Measures

The primary outcome was major adverse kidney events (MAKE), defined as a composite of mortality and worsened kidney function (estimated glomerular filtration rate [eGFR] decline by ≥25% from discharge eGFR or kidney failure requiring dialysis). Multivariable time-to-event analyses were performed to compare MAKE between individuals with COVID-AKI and those who had AKI associated with other illnesses hospitalized during the same period. For further comparison, this outcome was assessed for a historic cohort of patients with influenza-associated AKI.

Results

The study cohort included 9624 hospitalized patients (mean [SD] age, 69.0 [15.7] years; 4955 [51.5%] females) with AKI, including 987 patients with COVID-AKI, 276 with influenza-associated AKI, and 8361 with AKI associated with other illnesses (other-AKI). Compared with the other 2 groups, patients with COVID-19-associated AKI were slightly younger in age, had a higher baseline eGFR, worse baseline comorbidity scores, higher markers of illness severity, and longer hospital stay. Compared with the other-AKI group, the COVID-AKI group had lower MAKE (adjusted hazard ratio [aHR], 0.67; 95% CI, 0.59-0.75) due to lower all-cause mortality (aHR, 0.31; 95% CI, 0.24-0.39) and lower rates of worsened kidney function (aHR, 0.78; 95% CI, 0.69-0.88).

Conclusions and Relevance

The findings of this multicenter cohort study indicate that survivors of hospitalization with COVID-AKI experience lower rates of MAKE, long-term kidney function decline, and mortality compared with patients with AKI associated with other illnesses.

Acute Kidney Injury and Chronic Kidney Disease and Their Impacts on Prognosis among Patients with Severe COVID-19 Pneumonia: An Expert Center Case-Cohort Study

Background: Acute kidney injury (AKI) is associated with substantial mortality. In this case-control study, we analyzed the impacts of AKI and chronic kidney disease (CKD) on outcomes in a group of 323 patients with severe COVID-19. The correlation of clinical and laboratory data with AKI and CKD was also analyzed. Methods: A retrospective case-control study was conducted among AKI, CKD, and normal kidney function (NKF) groups hospitalized in a COVID-19 center in 2021. Results: AKI patients had higher in-hospital mortality (55.2 vs. 18.8%, p < 0.001), more frequent transfers from the HDU to ICU (57.5 vs. 12.9%, p < 0.001), and prolonged hospital stays (15.4 ± 10.7 vs. 10.7 ± 6.7 days, p < 0.001) compared to the NKF group. AKI was a predictor of death (OR 4.794, 95%CI: 2.906-7.906, p < 0.001). AKI patients also had broader lung parenchymal involvement and higher inflammatory markers compared to the NKF group. Patients with prior CKD had higher in-hospital mortality compared to the NKF group (64.0 vs. 18.8%, p < 0.001, OR 4.044, 95%CI: 1.723-9.490, p = 0.013); however, transfers from the HDU to ICU were not more frequent (16.0 vs. 12.9%, p = 0.753). Conclusions: AKI among COVID-19 patients was correlated with more ICU transfers, higher morbidity, and greater markers of severe disease. Patients with CKD had a higher mortality; however, the rate of ICU transfer was not substantially higher due to their poor prognosis.

COVID-19 and cardiovascular disease in patients with chronic kidney disease

Millions of people worldwide have chronic kidney disease (CKD). Affected patients are at high risk for cardiovascular (CV) disease for several reasons. Among various comorbidities, CKD is associated with the more severe forms of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. This is particularly true for patients receiving dialysis or for kidney recipients. From the start of the SARS-CoV-2 pandemic, several CV complications have been observed in affected subjects, spanning acute inflammatory manifestations, CV events, thrombotic episodes and arrythmias. Several pathogenetic mechanisms have been hypothesized, including direct cytopathic viral effects on the myocardium, endothelial damage and hypercoagulability. This spectrum of disease can occur during the acute phase of the infection, but also months after recovery. This review is focussed on the CV complications of coronavirus disease 2019 (COVID-19) with particular interest in their implications for the CKD population.

Evolution of in-hospital patient characteristics and predictors of death in the COVID-19 pandemic across four waves: are they moving targets with implications for patient care?

Objectives

The aim of this work was to study characteristics, outcomes and predictors of all-cause death in inpatients with SARS-CoV-2 infection across the pandemic waves in one large teaching hospital in Italy to optimize disease management.

Methods

All patients with SARS-CoV-2 infection admitted to our center from March 2020 to June 2022 were included in this retrospective observational cohort study. Both descriptive and regression tree analyses were applied to identify factors influencing all-cause mortality.

Results

527 patients were included in the study (65.3% with moderate and 34.7% with severe COVID-19). Significant evolutions of patient characteristics were found, and mortality increased in the last wave with respect to the third wave notwithstanding vaccination. Regression tree analysis showed that in-patients with severe COVID-19 had the greatest mortality across all waves, especially the older adults, while prognosis depended on the pandemic waves in patients with moderate COVID-19: during the first wave, dyspnea was the main predictor, while chronic kidney disease emerged as determinant factor afterwards.

Conclusion

Patients with severe COVID-19, especially the older adults during all waves, as well as those with moderate COVID-19 and concomitant chronic kidney disease during the most recent waves require more attention for monitoring and care. Therefore, our study drives attention towards the importance of co-morbidities and their clinical impact in patients with COVID-19 admitted to hospital, indicating that the healthcare system should adapt to the evolving features of the epidemic.

Long-term renal outcomes of patients with COVID-19: a meta-analysis of observational studies

BACKGROUND

Kidney involvement is common in hospitalized coronavirus disease 2019 (COVID-19) patients during the acute phase, little is known about the long-term impact of COVID-19 on the kidney.

METHODS

This is a systematic review and meta-analysis on long-term renal outcomes among COVID-19 patients. We carried out a systematic literature search in PUBMED, EMBASE, SCOPUS, and Cochrane COVID-19 study register and performed the random-effects meta-analysis of rates. The search was last updated on November 23, 2022.

RESULTS

The study included 12 moderate to high-quality cohort studies involving 6976 patients with COVID-19-associated acute kidney injury and 5223 COVID-19 patients without acute kidney injury. The summarized long-term renal non-recovery rate, dialysis-dependent rate, and complete recovery rate among patients with COVID-19-associated AKI was 22% (12-33%), 6% (2-12%), and 63% (44-81%) during a follow-up of 90-326.5 days. Heterogeneity could be explained by differences in the prevalence of chronic kidney disease and proportion of acute kidney injury requiring renal replacement therapy using meta-regression; patients with more comorbidities or higher renal replacement therapy rate had higher non-recovery rates. The summarized long-term kidney function decrease rate among patients without acute kidney injury was 22% (3-51%) in 90-199 days, with heterogeneity partially explained by severity of infection.

CONCLUSION

Patients with more comorbidities tend to have a higher renal non recovery rate after COVID-19-associated acute kidney injury; for COVID-19 patients without acute kidney injury, decrease in kidney function may occur during long-term follow-up. Regular evaluation of kidney function during the post-COVID-19 follow-up among high-risk patients may be necessary.

Risk of ischemic stroke in patients recovered from COVID-19 infection: A systematic review and meta-analysis

BACKGROUND

Data regarding the risk of ischemic stroke within 1 year after the post-acute phase of COVID-19 remain scant. We assess the risk of ischemic stroke in COVID-19 survivors after SARS-CoV-2 infection by performing a systematic review and meta-analysis of the available data.

METHODS

Following the PRISMA guidelines, we searched Medline and Scopus to locate all articles published up to February 11, 2023, reporting the risk of incident ischemic stroke in adult patients recovered from COVID-19 infection compared to non-infected patients (controls) defined as those who did not experience the infection over the same follow-up period. Ischemic stroke risk was evaluated using the Mantel-Haenszel random effects models with adjusted Hazard ratio (HR) as the effect measure with 95% confidence interval (CI) while heterogeneity was assessed using Higgins I2 statistic.

RESULTS

Overall, 23,559,428 patients (mean age 56, 1 year, 54.3% males), of whom 1,595,984 had COVID-19, were included. Over a mean follow-up of 9.2 months, ischemic stroke occurred in 4.40 [95% CI: 4.36-4.43] out of 1000 patients survived to COVID-19 compared to 3.25 [95% CI:3.21-3.29] out of 1000 controls. Recovered COVID-19 patients presented a higher risk of ischemic stroke ((HR: 2.06, 95% CI: 1.75-2.41, p < 0.0001, I2 = 63.7%) compared to people who did not have COVID-19. COVID-19 patients hospitalized at the time of the infection have a subsequent higher risk of stroke during the follow-up compared to those non-hospitalized.

CONCLUSIONS

Recovered COVID-19 patients have a higher risk of ischemic stroke compared to subjects from the general population within 9 months from the index infection.

Predictors of early and long-term mortality after ICU discharge in critically ill COVID-19 patients: A prospective cohort study

BACKGROUND

To mitigate mortality among critically ill COVID-19 patients, both during their Intensive Care Unit (ICU) stay and following ICU discharge, it is crucial to measure its frequency, identify predictors and to establish an appropriate post-ICU follow-up strategy.

METHODS

In this multicentre, prospective cohort study, we included 586 critically ill COVID-19 patients.

RESULTS

We observed an overall ICU mortality of 20.1% [95%CI: 17.1% to 23.6%] (118/586) and an overall hospital mortality of 25.4% [95%CI: 22.1% to 29.1%] (149/586). For ICU survivors, 30 days (early) post-ICU mortality was 5.3% [95%CI: 3.6% to 7.8%] (25/468) and one-year (late) post-ICU mortality was 7.9% [95%CI: 5.8% to 10.8%] (37/468). Pre-existing conditions/comorbidities were identified as the main independent predictors of mortality after ICU discharge: hypertension and heart failure were independent predictors of early mortality; and hypertension, chronic kidney disease, chronic obstructive pulmonary disease and cancer were independent predictors of late mortality.

CONCLUSION

Early and late post-ICU mortality exhibited an initial surge (in the first 30 days post-ICU) followed by a subsequent decline over time. Close monitoring of critically ill COVID-19 post-ICU survivors, especially those with pre-existing conditions, is crucial to prevent adverse outcomes, reduce mortality and to establish an appropriate follow-up strategy.

COVID-19 and Kidney: The Importance of Follow-Up and Long-Term Screening

Renal involvement and kidney injury are common in COVID-19 patients, and the symptoms are more severe if the patient already has renal impairment. Renal involvement in COVID-19 is multifactorial, and the renal tubule is mainly affected, along with podocyte injury during SARS-CoV-2 infection. Inflammation, complement activation, hypercoagulation, and crosstalk between the kidney and lungs, brain, and heart are contributory factors. Kidney injury during the acute phase, termed acute kidney injury (AKI), may proceed to chronic kidney disease if the patient is discharged with renal impairment. Both AKI and chronic kidney disease (CKD) increase mortality in COVID-19 patients. Further, COVID-19 infection in patients suffering from CKD is more severe and increases the mortality rate. Thus, it is important to address both categories of patients, either developing AKI or CKD after COVID-19 or previously having CKD, with proper management and treatment. This review discusses the pathophysiology involved in AKI and CKD in COVID-19 infection, followed by management and treatment of AKI and CKD. This is followed by a discussion of the importance of screening and treatment of CKD patients infected with COVID-19 and future perspectives to improve treatment in such patients.

Comparison of different prognostic scores in estimating short- and long-term mortality in COVID-19 patients above 60 years old in a university hospital in Belgium

BACKGROUND AND OBJECTIVES

Multiple scoring systems were used for risk stratification in COVID-19 patients. The objective was to determine among 6 scores which performed the best in predicting short-and long-term mortality in hospitalized COVID-19 patients ≥ 60 years.

METHODS

An observational, retrospective cohort study conducted between 21/10/2020 and 20/01/2021. 6 scores were calculated (Clinical Frailty Scale (CFS), Charlson Comorbidity Index (CCI), 4C Mortality Score (4CMS), NEWS score (NEWS), quick-SOFA score (qSOFA), and Quick COVID-19 Severity Index (qCSI)). We included unvaccinated hospitalized patients with COVID-19 ≥ 60 years old in Brugmann hospital, detected by PCR and/or suggestive CT thorax images. Old and nosocomial infections, and patients admitted immediately at the intensive care unit were excluded.

RESULTS

199 patients were included, mean age was 76.2 years (60-99). 47.2% were female. 56 patients (28%) died within 1 year after the first day of hospitalization. The 4CMS predicted the best intrahospital, 30 days and 6 months mortality, with area under the ROC curve (AUROC) 0.695 (0.58-0.81), 0.76 (0.65-0.86) and 0.72 (0.63-0.82) respectively. The CCI came right after with respectively AUROC of 0.69 (0.59-0.79), 0.74 (0.65-0.83) and 0.71 (0.64-0.8). To predict mortality at 12 months after hospitalization, the CCI had the highest AUROC with 0.77 (0.69-0.85), before the 4CMS with 0.69 (0.60-0.79).

DISCUSSION

Among 6 scores, the 4CMS was the best to predict intrahospital, 30-day and 6-month mortality. To predict mortality at 12 months, CCI had the best performance before 4CMS. This reflects the importance of considering comorbidities for short- and long-term mortality after COVID 19.

REGISTRATION

This study was approved by the ethical committee of Brugmann University Hospital (reference CE 2020/228).

Long-term outcomes of COVID-19 survivors with hospital AKI: association with time to recovery from AKI

BACKGROUND

Although coronavirus disease 2019 (COVID-19) patients who develop in-hospital acute kidney injury (AKI) have worse short-term outcomes, their long-term outcomes have not been fully characterized. We investigated 90-day and 1-year outcomes after hospital AKI grouped by time to recovery from AKI.

METHODS

This study consisted of 3296 COVID-19 patients with hospital AKI stratified by early recovery (<48 hours), delayed recovery (2-7 days) and prolonged recovery (>7-90 days). Demographics, comorbidities and laboratory values were obtained at admission and up to the 1-year follow-up. The incidence of major adverse cardiovascular events (MACE) and major adverse kidney events (MAKE), rehospitalization, recurrent AKI and new-onset chronic kidney disease (CKD) were obtained 90-days after COVID-19 discharge.

RESULTS

The incidence of hospital AKI was 28.6%. Of the COVID-19 patients with AKI, 58.0% experienced early recovery, 14.8% delayed recovery and 27.1% prolonged recovery. Patients with a longer AKI recovery time had a higher prevalence of CKD (P < .05) and were more likely to need invasive mechanical ventilation (P < .001) and to die (P < .001). Many COVID-19 patients developed MAKE, recurrent AKI and new-onset CKD within 90 days, and these incidences were higher in the prolonged recovery group (P < .05). The incidence of MACE peaked 20-40 days postdischarge, whereas MAKE peaked 80-90 days postdischarge. Logistic regression models predicted 90-day MACE and MAKE with 82.4 ± 1.6% and 79.6 ± 2.3% accuracy, respectively.

CONCLUSION

COVID-19 survivors who developed hospital AKI are at high risk for adverse cardiovascular and kidney outcomes, especially those with longer AKI recovery times and those with a history of CKD. These patients may require long-term follow-up for cardiac and kidney complications.

Strategies and Trends in COVID-19 Vaccination Delivery: What We Learn and What We May Use for the Future

Vaccination has been the most effective way to control the outbreak of the COVID-19 pandemic. The numbers and types of vaccines have reached considerable proportions, even if the question of vaccine procedures and frequency still needs to be resolved. We have come to learn the necessity of defining vaccination distribution strategies with regard to COVID-19 that could be used for any future pandemics of similar gravity. In fact, vaccine monitoring implies the existence of a strategy that should be measurable in terms of input and output, based on a mathematical model, including death rates, the spread of infections, symptoms, hospitalization, and so on. This paper addresses the issue of vaccine diffusion and strategies for monitoring the pandemic. It provides a description of the importance and take up of vaccines and the links between procedures and the containment of COVID-19 variants, as well as the long-term effects. Finally, the paper focuses on the global scenario in a world undergoing profound social and political change, with particular attention on current and future health provision. This contribution would represent an example of vaccination experiences, which can be useful in other pandemic or epidemiological contexts.

COVID and the Kidney: An Update

Coronavirus disease-2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2, has led to a global pandemic that continues to be responsible for ongoing health issues for people worldwide. Immunocompromised individuals such as kidney transplant recipients and dialysis patients have been and continue to be among the most affected, with poorer outcomes after infection, impaired response to COVID-19 vaccines, and protracted infection. The pandemic also has had a significant impact on patients with underlying chronic kidney disease (CKD), with CKD increasing susceptibility to COVID-19, risk of hospital admission, and mortality. COVID-19 also has been shown to lead to acute kidney injury (AKI) through both direct and indirect mechanisms. The incidence of COVID-19 AKI has been decreasing as the pandemic has evolved, but continues to be associated with adverse patient outcomes correlating with the severity of AKI. There is also increasing evidence examining the longer-term effect of COVID-19 on the kidney demonstrating continued decline in kidney function several months after infection. This review summarizes the current evidence examining the impact of COVID-19 on the kidney, covering both the impact on patients with CKD, including patients receiving kidney replacement therapy, in addition to discussing COVID-19 AKI.

Infections and Acute Kidney Injury: A Global Perspective

Globally, there are an estimated 13.3 million cases of acute kidney injury (AKI) annually. Although infections are a common cause of AKI globally, most infection-associated AKI occurs in low- and lower-middle-income countries. There are marked differences in the etiology of infection-associated AKI across age groups, populations at risk, and geographic location. This article provides a global overview of different infections that are associated commonly with AKI, including severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), human immunodeficiency virus, malaria, dengue, leptospirosis, tick-borne illnesses, and viral hemorrhagic fevers. Further discussion focuses on infectious conditions associated with AKI including sepsis, diarrheal diseases and pregnancy, peripartum and neonatal AKI. This article also discusses the future of infection-associated AKI in the framework of climate change. It explores how increased investment in achieving the sustainable development goals may contribute to the International Society of Nephrology's 0 by 25 objective to curtail avoidable AKI-related fatalities by 2025.

Our Experience with SARS-CoV-2 Infection and Acute Kidney Injury: Results from a Single-Center Retrospective Observational Study

BACKGROUND

Renal failure in COVID-19 patients is reportedly related to multiple factors such as a direct SARS-CoV-2 cytopathic effect, cytokine storm, the association of pulmonary and/or cardiovascular lesions, the presence of thrombotic microangiopathy, endothelial damage, or the use of potentially nephrotoxic medications.

METHODS

We retrospectively analyzed 466 cases of SARS-CoV-2 infection, comparing 233 patients with acute kidney injury (AKI) with 233 patients without AKI in terms of their demographic characteristics, comorbidities, clinical background, laboratory investigations, time of AKI onset, therapy, and outcomes after using univariate analysis and a CART decision-tree approach. The latter was constructed in a reverse manner, starting from the top with the root and branching out until the splitting ceased, interconnecting all the predictors to predict the overall outcome (AKI vs. non-AKI).

RESULTS

There was a statistically significant difference between the clinical form distribution in the two groups, with fewer mild (2 vs. 5) and moderate (54 vs. 133) cases in the AKI group than in the non-AKI group and more severe and critical patients in the AKI cohort (116 vs. 92 and 60 vs. 3). There were four deaths (1.71%) in the non-AKI group and 120 deaths in the AKI group (51.5%) (p-value < 0.001). We noted statistically significant differences between the two study groups in relation to different tissue lesions (LDH), particularly at the pulmonary (CT severity score), hepatic (AST, ALT), and muscular levels (Creatine kinase). In addition, an exacerbated procoagulant and inflammatory profile in the study group was observed. The CART algorithm approach yielded decision paths that helped sort the risk of AKI progression into three categories: the low-risk category (0-40%), the medium-risk category (40-80%), and the high-risk category (>80%). It recognized specific inflammatory and renal biomarker profiles with particular cut-off points for procalcitonin, ferritin, LDH, creatinine, initial urea, and creatinine levels as important predictive factors of AKI outcomes (93.3% overall performance).

CONCLUSIONS

Our study revealed the association between particular risk factors and AKI progression in COVID-19 patients. Diabetes, dyspnea on admission, the need for supplemental oxygen, and admission to the intensive care unit all had a crucial role in producing unfavorable outcomes, with a death rate of more than 50%. Necessary imaging studies (CT scan severity score) and changes in specific biomarker levels (ferritin and C-reactive protein levels) were also noted. These factors should be further investigated in conjunction with the pathophysiological mechanisms of AKI progression in COVID-19 patients.

Real-life comparison of mortality in patients with SARS-CoV-2 infection at risk for clinical progression treated with molnupiravir or nirmatrelvir plus ritonavir during the Omicron era in Italy: a nationwide, cohort study

Background

Comparative data on mortality in COVID-19 patients treated with molnupiravir or with nirmatrelvir plus ritonavir are inconclusive. We therefore compared all-cause mortality in community-dwelling COVID-19 patients treated with these drugs during the Omicron era.

Methods

Data collected in the nationwide, population-based, cohort of patients registered in the database of the Italian Medicines Agency (AIFA) were used. To increase completeness of the recorded deaths and date correctness, a cross-check with the National Death Registry provided by the Ministry of the Interior was performed. We included in this study all patients infected by SARS-CoV-2 treated within 5 days after the test date and symptom onset between February 8 and April 30, 2022. All-cause mortalities by day 28 were compared between the two treatment groups after balancing for baseline characteristics using weights obtained from a gradient boosting machine algorithm.

Findings

In the considered timeframe, 17,977 patients treated with molnupiravir and 11,576 patients with nirmatrelvir plus ritonavir were included in the analysis. Most patients (25,617/29,553 = 86.7%) received a full vaccine course including the booster dose. A higher crude incidence rate of all-cause mortality was found among molnupiravir users (51.83 per 100,000 person-days), compared to nirmatrelvir plus ritonavir users (22.29 per 100,000 person-days). However, molnupiravir-treated patients were older than those treated with nirmatrelvir plus ritonavir and differences between the two populations were found as far as types of co-morbidities were concerned. For this reason, we compared the weight-adjusted cumulative incidences using the Aalen estimator and found that the adjusted cumulative incidence rates were 1.23% (95% CI 1.07%-1.38%) for molnupiravir-treated and 0.78% (95% CI 0.58%-0.98%) for nirmatrelvir plus ritonavir-treated patients (adjusted log rank p = 0.0002). Moreover, the weight-adjusted mixed-effect Cox model including Italian regions and NHS centers as random effects and treatment as the only covariate confirmed a significant reduced risk of death in patients treated with nirmatrelvir plus ritonavir. Lastly, a significant reduction in the risk of death associated with nirmatrelvir plus ritonavir was confirmed in patient subgroups, such as in females, fully vaccinated patients, those treated within day 2 since symptom onset and patients without (haemato)-oncological diseases.

Interpretation

Early initiation of nirmatrelvir plus ritonavir was associated for the first time with a significantly reduced risk of all-cause mortality by day 28 compared to molnupiravir, both in the overall population and in patient subgroups, including those fully vaccinated with the booster dose.

Funding

This study did not receive funding.

Endothelial dysfunction in autoimmune, pulmonary, and kidney systems, and exercise tolerance following SARS-CoV-2 infection

Long COVID is characterized by persistent symptoms beyond 3-months of severe acute respiratory syndrome Coronavirus-2 (SARS-CoV-2) infection that last for at least 2 months and cannot be explained by an alternative diagnosis. Autonomic, immunologic, endothelial, and hypercoagulation are implicated as possible mechanisms of long COVID symptoms. Despite recognition of the public health challenges posed by long COVID, the current understanding of the pathophysiological underpinnings is still evolving. In this narrative review, we explore the long-term effects of SARS-CoV-2 infection on T cell activation such as autoimmune disorders and endothelial cell dysfunction involving vascular impairments within pulmonary and renal architecture. We have described how endothelial dysfunction and vascular abnormalities may underscore findings of exercise intolerance by way of impaired peripheral oxygen extraction in individuals with long COVID.

Kidney Injury in Critically Ill Patients with COVID-19 - From Pathophysiological Mechanisms to a Personalized Therapeutic Model

Acute kidney injury is a common complication of COVID-19, frequently fuelled by a complex interplay of factors. These include tubular injury and three primary drivers of cardiocirculatory instability: heart-lung interaction abnormalities, myocardial damage, and disturbances in fluid balance. Further complicating this dynamic, renal vulnerability to a "second-hit" injury, like a SARS-CoV-2 infection, is heightened by advanced age, chronic kidney disease, cardiovascular diseases, and diabetes mellitus. Moreover, the influence of chronic treatment protocols, which may constrain the compensatory intrarenal hemodynamic mechanisms, warrants equal consideration. COVID-19-associated acute kidney injury not only escalates mortality rates but also significantly affects long-term kidney function recovery, particularly in severe instances. Thus, the imperative lies in developing and applying therapeutic strategies capable of warding off acute kidney injury and decelerating the transition into chronic kidney disease after an acute event. This narrative review aims to proffer a flexible diagnostic and therapeutic strategy that recognizes the multi-faceted nature of COVID-19-associated acute kidney injury in critically ill patients and underlines the crucial role of a tailored, overarching hemodynamic and respiratory framework in managing this complex clinical condition.

Modified Banff Criteria in Assessing SARS-CoV-2-Associated Renal Pathology: An Autopsy Study

Introduction SARS-CoV-2 is an epitheliotropic viral agent with epithelial tropism. Although the clinical significance and severity of affection is the most pronounced in the respiratory system, other organs and systems are also infected and, hence affected, such as the central nervous system, gastrointestinal tract, cardiovascular, and urinary systems. Herein, we set out to evaluate the presence and degree of morphological changes within the renal parenchyma and its relation to disease outcome. Materials and methods A retrospective non-clinical approach was utilized for the means of the study. All patients with real-time reverse transcriptase-polymerase chain reaction proven infection, subject to an autopsy performed in a period of two calendar years, were included in the study. Kidney tissue histopathology samples were analyzed using a modified Banff criteria system for acute onset and chronic changes. The results were compared for statistical significance with overall patient survival from symptom onset to death. Furthermore, SARS-CoV-2 viral presence was evaluated in renal structures by means of immunohistochemistry. Results A total of 40 patients were included in the study. Immunohistochemistry showed viral presence within a myriad of renal structured - endothelial cells, tubular cells, and podocytes. Modified Banff criteria showed significant acute changes within the parenchyma, including endotheliitis, glomerulitis, mesangial matrix expansion, tubulitis, capillaritis, arteritis, thrombosis (including thrombotic microangiopathy in four patients), and hemorrhages. Individual cases also presented with signs of rhabdomyolysis - myoglobulin casts. Signs of chronic injury were also present in most patients. However, when calculated as scores, neither acute nor chronic changes showed a correlation with time from symptom onset to death. Conclusion The results of the present study show both viral presence and a myriad of induced changes in the contents of SARS-CoV-2 infection within the renal parenchyma. The lack of correlation with the degree of changes, when compared to survival, is an encouraging fact that the changes are unlikely to play a role in direct tanatogenesis while having the potential to manifest as chronic kidney disease in the future.

The three facets of the SARS-CoV-2 pandemic during the first two waves in the northern, central, and southern Italy

BACKGROUND

There is a scarcity of information in literature regarding the clinical differences and comorbidities of patients affected by Coronavirus disease 2019 (COVID-19), which could clarify the different prevalence of the outcomes (composite and only death) between several Italian regions.

OBJECTIVE

This study aimed to assess the heterogeneity of clinical features of patients with COVID-19 upon hospital admission and disease outcomes in the northern, central, and southern Italian regions.

METHODS

An observational cohort multicenter retrospective study including 1210 patients who were admitted for COVID-19 in Infectious diseases, Pulmonology, Endocrinology, Geriatrics and Internal Medicine Units in Italian cities stratified between north (263 patients); center (320 patients); and south (627 patients), during the first and second pandemic waves of SARS-CoV-2 (from February 1, 2020 to January 31, 2021). The data, obtained from clinical charts and collected in a single database, comprehended demographic characteristics, comorbidities, hospital and home pharmacological therapies, oxygen therapy, laboratory values, discharge, death and Intensive care Unit (ICU) transfer. Death or ICU transfer were defined as composite outcomes.

RESULTS

Male patients were more frequent in the northern Italian region than in the central and southern regions. Diabetes mellitus, arterial hypertension, chronic pulmonary and chronic kidney diseases were the comorbidities more frequent in the southern region; cancer, heart failure, stroke and atrial fibrillation were more frequent in the central region. The prevalence of the composite outcome was recorded more frequently in the southern region. Multivariable analysis showed a direct association between the combined event and age, ischemic cardiac disease, and chronic kidney disease, in addition to the geographical area.

CONCLUSIONS

Statistically significant heterogeneity was observed in patients with COVID-19 characteristics at admission and outcomes from northern to southern Italy. The higher frequency of ICU transfer and death in the southern region may depend on the wider hospital admission of frail patients for the availability of more beds since the burden of COVID-19 on the healthcare system was less intense in southern region. In any case, predictive analysis of clinical outcomes should consider that the geographical differences that may reflect clinical differences in patient characteristics, are also related to access to health-care facilities and care modalities. Overall, the present results caution against generalizability of prognostic scores in COVID-19 patients derived from hospital cohorts in different settings.

Evaluation of Remdesivir Utilization Pattern in Critically Ill Patients With COVID-19 in Jazan Province

Background Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the virus that causes coronavirus disease 2019 (COVID-19), has spread around the world, spurring the biomedical community to find and create antiviral therapies. The agent remdesivir, which has undergone a protracted and tortuous developmental path, is one potential therapeutic strategy now being assessed in several clinical trials. A broad-spectrum antiviral drug called remdesivir has already shown antiviral effects against filoviruses. Remdesivir was suggested as an exploratory medicine early in the pandemic because in vitro tests showed it to have antiviral effectiveness against SARS-CoV-2. Methods We conducted a retrospective cohort study that examined patient data captured through an electronic medical system at the Abu Arish General Hospital between 2021 and 2022. Data analysis was performed with SPSS version 25.0 (Armonk, NY: IBM Corp.). Results A total of 88 patients were included in this study. With the usage of remdesivir, our risk model is able to forecast adverse events and the case fatality rate. In contrast to D-dimer and c-reactive proteins, we showed that alanine transaminase (ALT), aspartate aminotransferase (AST), serum creatinine, and hemoglobin are relevant variables. Conclusion Our risk model can predict the adverse reactions and case fatality rate with the use of remdesivir. We demonstrated ALT, AST, serum creatinine, and hemoglobin as important variables rather than D-dimer and c-reactive proteins.

Acute kidney injury in Coronavirus disease-19 related pneumonia in the intensive care unit: a retrospective multicenter study, Saudi Arabia

Background

Acute kidney injury (AKI) poses a significant morbidity and mortality risk to critically ill COVID-19 patients. The aim of this study was to investigate the incidence, predictors, and outcomes of AKI in patients admitted to the intensive care unit (ICU) with critically ill COVID-19 pneumonia.

Methods

A multicenter retrospective study in Saudi Arabia of adult patients aged at least 18 years diagnosed with COVID-19 pneumonia and admitted to the intensive care unit between May 2020 and May 2021 was conducted. The occurrence of AKI and associated risk factors, the need for continous renal replacement therapy (CRRT), and the outcome were reported.

Results

The study included 340 patients admitted to the ICU with COVID-19. Their mean age was 66.7±13.4 years, ranging from 49 to 84 years, and most of them were men (63.8%). The most common concomitant diseases were hypertension (71.5%), diabetes (62.4%), IHD (37.6%), CKD (20%), heart failure (19.4%), and 81.2% suffered from ARDS. AKI occurred in 60.3% of patients, 38% were stage 1, 16.6% were stage 2, and 45.4% were stage 3. Approximately, 39% of patients required CRRT, out of which 76.2% were stage 3, which was significantly higher than the other stages (p<0.001). AKI patients suffered significantly from asthma and had lower levels of C-reactive protein (CRP), ferritin, lactate dehydrogenase (LDH), and blood urea nitrogen (BUN) and higher creatinine levels than patients without AKI (p<0.05 all). The overall mortality rate was 39.4%, and the mortality rate was significantly higher in patients with AKI than in patients without AKI (48.3% versus 25.9%; p<0.001).

Conclusion

AKI is common in adults admitted to the ICU with COVID-19 and is associated with an increased risk of death. Early detection of AKI and appropriate treatment can positively impact COVID-19 outcome. CRRT is the preferred dialysis method in critically ill ICU patients with AKI.