SARS-CoV-2 infection causes a decline in renal megalin expression and affects vitamin D metabolism in the kidney of K18-hACE2 mice

Patients with coronavirus disease 2019 (COVID-19) often experience acute kidney injury, linked to disease severity or mortality, along with renal tubular dysfunction and megalin loss in proximal tubules. Megalin plays a crucial role in kidney vitamin D metabolism. However, the impact of megalin loss on vitamin D metabolism during COVID-19 is unclear. This study investigated whether severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection reduces megalin expression in proximal tubules and its subsequent effect on vitamin D metabolism in mice expressing human angiotensin converting enzyme 2 (K18-hACE2 mice). Histological and immunohistochemical staining analyses revealed glomerular and capillary congestion, and elevated renal neutrophil gelatinase-associated lipocalin levels, indicative of acute kidney injury in K18-hACE2 mice. In SARS-CoV-2-infected mice, immunohistochemical staining revealed suppressed megalin protein levels. Decreased vitamin D receptor (VDR) localization in the nucleus and increased mRNA expression of VDR, CYP27B1, and CYP24A1 were observed by quantitative PCR in SARS-CoV-2-infected mice. Serum vitamin D levels remained similar in infected and vehicle-treated mice, but an increase in tumor necrosis factor-alpha and a decrease in IL-4 mRNA expression were observed in the kidneys of the SARS-CoV-2 group. These findings suggest that megalin loss in SARS-CoV-2 infection may impact the local role of vitamin D in kidney immunomodulation, even when blood vitamin D levels remain unchanged.

Acyclovir treatment of varicella-zoster virus meningeal infections and acute kidney injury: a multicentre case series study

BACKGROUND

Systematic treatment with intravenous acyclovir is usually given when varicella zoster virus (VZV) DNA is isolated in cerebrospinal fluid (CSF), indicating central nervous system (CNS) involvement. Our study aimed to describe therapeutic management and acute kidney injury (AKI) occurrence during acyclovir treatment of VZV infection with CNS involvement.

METHODS

Multicentre, retrospective study including all patients from 2010 to 2022 with VZV DNA in CSF. Patient management and outcomes were compared according to clinical presentation and indications for intravenous acyclovir: i) definite (encephalitis, myelitis or stroke, peripheral nervous system (PNS) with ≥ 2 roots, herpes zoster ≥ 3 dermatomes, immunosuppression), ii) questionable (1 or 2 dermatomes) or iii) no indication (other situations).

RESULTS

154 patients were included (median age 66 (interquartile range 43-77), 87 (56%) males); 60 (39%) had encephalitis, myelitis or stroke, 35 (23%) had PNS involvement, 37 (24%) had isolated meningitis, 14 (9%) had isolated cutaneous presentation, and 8 (5%) had other presentations. Overall, 128 (83%) received intravenous acyclovir for more than 72 h. AKI occurred in 57 (37%) patients. Finally, 42 (27%) and 25 (16%) patients had respectively no or a questionable indication for intravenous acyclovir, while 29 (69%) and 23 (92%) of them received it for more than 72 h, with AKI in 13 (35%) and 13 (52%) patients, respectively. In-hospital mortality was 12% (n = 18), and no deaths were reported in isolated meningitis.

CONCLUSIONS

Intravenous acyclovir is widely prescribed when VZV DNA is isolated in CSF, regardless of the clinical presentation, with a high rate of AKI. Further studies are needed to better define the value of intravenous acyclovir in isolated VZV meningitis.

Emerging fatal gout disease in Chinese goslings linked to acute kidney injury induced by novel goose astrovirus infection

A novel goose astrovirus (GAstV) has broken out across China in recent years, causing widespread damage to the poultry industry. In goslings infected with GAstV, the leading cause of death is visceral gout. However, our understanding of the mechanism of gout formation in GAstV infection is largely inadequate. The aim of this study was to examine the pathogenicity of a GAstV strain and explore the molecular mechanisms of visceral gout caused by viral infection in goslings. The virulent GAstV strain HR2105/1 was effectively isolated from the visceral tissue of goslings in gout-affected areas. The whole genome of the HR2105/1 strain was sequenced and analyzed. Subsequently, we established a gosling gout models with experimental GAstV infection. Finally, we conducted a study on the mechanism of GAstV induced acute kidney injury. Phylogenetic analysis of the complete genome sequence showed that it was closely related to the strain circulating in China since 2016, and it was grouped within the GAstV-1 cluster. The clinical signs were reproduced by experimental infection of healthy goslings with the isolated strain and were found to be similar to those reported in clinical cases. Moreover, the virus exhibits strong renal tropism. Infection with the GAstV strain HR2105/1 was found to cause acute kidney injury, as evidenced by increased levels of uric acid and creatinine as well as severe pathological damage. Mechanistic experiments with Masson and Picrosirius Red staining revealed fibrosis in renal tissues after GAstV infection. Furthermore, TUNEL staining revealed that GAstV infection triggered renal cell apoptosis. Additionally, RT-qPCR revealed that GAstV infection caused an excessive inflammatory response by upregulating the expression of IL-1β, IL-6, IL-10, TGF-β, and iNOS in renal tissues. Overall, our findings demonstrate that GAstV infection causes renal damage by inducing renal cell apoptosis, fibrosis, and excessive inflammatory response, which subsequently leads to hyperuricemia and lethal visceral gout formation. This is the first systematic study on the etiology of lethal gout in goslings caused by GAstV infection, and we believe that the findings can guide vaccine development and therapeutic targets for GAstV-associated renal diseases.

Rhabdomyolysis, Acute Kidney Injury, and Mortality in Ebola Virus Disease: Retrospective Analysis of Cases From the Eastern Democratic Republic of the Congo, 2019

BACKGROUND

Skeletal muscle injury in Ebola virus disease (EVD) has been reported, but its association with morbidity and mortality remains poorly defined.

METHODS

This retrospective study included patients admitted to 2 EVD treatment units over an 8-month period in 2019 during an EVD epidemic in the Democratic Republic of the Congo.

RESULTS

An overall 333 patients (median age, 30 years; 58% female) had at least 1 creatine kinase (CK) measurement (n = 2229; median, 5/patient [IQR, 1-11]). Among patients, 271 (81%) had an elevated CK level (>380 U/L); 202 (61%) had rhabdomyolysis (CK >1000 IU/L); and 45 (14%) had severe rhabdomyolysis (≥5000 U/L). Among survivors, the maximum CK level was a median 1600 (IQR, 550-3400), peaking 3.4 days after admission (IQR, 2.3-5.5) and decreasing thereafter. Among fatal cases, the CK rose monotonically until death, with a median maximum CK level of 2900 U/L (IQR, 1500-4900). Rhabdomyolysis at admission was an independent predictor of acute kidney injury (adjusted odds ratio, 2.2 [95% CI, 1.2-3.8]; P = .0065) and mortality (adjusted hazard ratio, 1.7 [95% CI, 1.03-2.9]; P = .037).

CONCLUSIONS

Rhabdomyolysis is associated with acute kidney injury and mortality in patients with EVD. These findings may inform clinical practice by identifying laboratory monitoring priorities and highlighting the importance of fluid management.

Kidney Outcomes and Trajectories of Tubular Injury and Function in Critically Ill Patients With and Without COVID-19

IMPORTANCE

COVID-19 may injure the kidney tubules via activation of inflammatory host responses and/or direct viral infiltration. Most studies of kidney injury in COVID-19 lacked contemporaneous controls or measured kidney biomarkers at a single time point.

OBJECTIVES

To better understand mechanisms of acute kidney injury in COVID-19, we compared kidney outcomes and trajectories of tubular injury, viability, and function in prospectively enrolled critically ill adults with and without COVID-19.

DESIGN, SETTING, AND PARTICIPANTS

The COVID-19 Host Response and Outcomes study prospectively enrolled patients admitted to ICUs in Washington State with symptoms of lower respiratory tract infection, determining COVID-19 status by nucleic acid amplification on arrival.

MAIN OUTCOMES AND MEASURES

We evaluated major adverse kidney events (MAKE) defined as a doubling of serum creatinine, kidney replacement therapy, or death, in 330 patients after inverse probability weighting. In the 181 patients with available biosamples, we determined trajectories of urine kidney injury molecule-1 (KIM-1) and epithelial growth factor (EGF), and urine:plasma ratios of endogenous markers of tubular secretory clearance.

RESULTS

At ICU admission, the mean age was 55 ± 16 years; 45% required mechanical ventilation; and the mean serum creatinine concentration was 1.1 mg/dL. COVID-19 was associated with a 70% greater occurrence of MAKE (relative risk 1.70; 95% CI, 1.05-2.74) and a 741% greater occurrence of KRT (relative risk 7.41; 95% CI, 1.69-32.41). The biomarker cohort had a median of three follow-up measurements. Urine EGF, secretory clearance ratios, and estimated glomerular filtration rate (eGFR) increased over time in the COVID-19 negative group but remained unchanged in the COVID-19 positive group. In contrast, urine KIM-1 concentrations did not significantly change over the course of the study in either group.

CONCLUSIONS

Among critically ill adults, COVID-19 is associated with a more protracted course of proximal tubular dysfunction and reduced eGFR despite similar degrees of kidney injury.

JAK inhibition during the early phase of SARS-CoV-2 infection worsens kidney injury by suppressing endogenous antiviral activity in mice

Coronavirus disease 2019 (COVID-19) induces respiratory dysfunction as well as kidney injury. Although the kidney is considered a target organ of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and affected by the COVID-19-induced cytokine storm, the mechanisms of renal reaction in SARS-CoV-2 infection are unknown. In this study, a murine COVID-19 model was induced by nasal infection with mouse-adapted SARS-CoV-2 (MA10). MA10 infection induced body weight loss along with lung inflammation in mice 4 days after infection. Serum creatinine levels and the urinary albumin/creatinine ratio increased on day 4 after MA10 infection. Measurement of the urinary neutrophil gelatinase-associated lipocalin/creatinine ratio and hematoxylin and eosin staining revealed tubular damage in MA10-infected murine kidneys, indicating kidney injury in the murine COVID-19 model. Interferon (IFN)-γ and interleukin-6 upregulation in the sera of MA10-infected mice, along with the absence of MA10 in the kidneys, implied that the kidneys were affected by the MA10 infection-induced cytokine storm rather than by direct MA10 infection of the kidneys. RNA-sequencing analysis revealed that antiviral genes, such as the IFN/Janus kinase (JAK) pathway, were upregulated in MA10-infected kidneys. Upon administration of the JAK inhibitor baricitinib on days 1-3 after MA10 infection, an antiviral pathway was suppressed, and MA10 was detected more frequently in the kidneys. Notably, JAK inhibition upregulated the hypoxia response and exaggerated kidney injury. These results suggest that endogenous antiviral activity protects against SARS-CoV-2-induced kidney injury in the early phase of infection, providing valuable insights into the pathogenesis of COVID-19-associated nephropathy.NEW & NOTEWORTHY Patients frequently present with acute kidney injury or abnormal urinary findings after severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Here, we investigated how the kidneys respond during SARS-CoV-2 infection using a murine coronavirus disease 2019 (COVID-19) model and showed that Janus kinase-mediated endogenous antiviral activity protects against kidney injury in the early phase of SARS-CoV-2 infection. These findings provide valuable insights into the renal pathophysiology of COVID-19.

Associations between Different Antivirals and Hospital-Acquired Acute Kidney Injury in Adults with Herpes Zoster

Key Points

Among intravenous antivirals, acyclovir was associated with the highest risk of hospital-acquired AKI, followed by penciclovir/ganciclovir and foscarnet. The risk of hospital-acquired AKI was dose dependent for intravenous nucleoside analogs.

Background

To examine the association of use of different antivirals with hospital-acquired AKI among Chinese adults with herpes zoster.

Methods

This study selected 3273 adult patients who received antiviral therapy for herpes zoster during hospitalization from the China Renal Data System. We identified and staged AKI using patient-level serum creatinine data according to the Kidney Disease Improving Global Outcomes criteria. We compared the relative risks of hospital-acquired AKI among patients treated with different antivirals using Cox proportional hazards models.

Results

Among 3273 patients, 1480 (45%), 681 (21%), 489 (15%), and 623 (19%) were treated with acyclovir/valacyclovir, ganciclovir, penciclovir/famciclovir, and foscarnet, respectively. During the follow-up period, a total of 111 cases of hospital-acquired AKI occurred, predominantly classified as AKI stage 1. The cumulative incidences of hospital-acquired AKI were 5%, 3%, 3%, and 1% in the patients receiving acyclovir/valacyclovir, ganciclovir, penciclovir/famciclovir, and foscarnet, respectively. Compared with acyclovir/valacyclovir, penciclovir/famciclovir/ganciclovir and foscarnet were associated with a lower risk of hospital-acquired AKI, with an adjusted hazard ratio of 0.59 (95% confidence interval [CI], 0.37 to 0.94) and 0.27 (95% CI, 0.11 to 0.63), respectively. Compared with intravenous acyclovir, intravenous penciclovir/ganciclovir and foscarnet were associated with a lower risk of hospital-acquired AKI with an adjusted hazard ratio of 0.53 (95% CI, 0.29 to 0.98) and 0.31 (95% CI, 0.12 to 0.76), respectively. The associations were consistent across various subgroups and sensitivity analyses.

Conclusions

Among antiviral therapies for herpes zoster, we found different risks of hospital-acquired AKI among the patients receiving different antivirals, in particular, those administered intravenously. Among intravenous antivirals, acyclovir was associated with the highest risk of hospital-acquired AKI, followed by penciclovir/ganciclovir and foscarnet. Confirmation studies with large samples from other populations are warranted.

Neutrophil-to-lymphocyte ratio is elevated in acute hantavirus infection and correlates with markers of disease severity

Pathogenic Eurasian hantaviruses cause hemorrhagic fever with renal syndrome (HFRS), which is characterized by acute kidney injury. The clinical course shows a broad range of severity and is influenced by direct and immune-mediated effects. The neutrophil-to-lymphocyte ratio (NLR) is a marker of systemic inflammation and predicts severity and outcome in various diseases. Therefore, we examined the role of NLR in HFRS caused by hantavirus Puumala (PUUV) and its association with disease severity and kidney injury. We detected elevated NLR levels on admission (NLRadm: median 3.82, range 1.75-7.59), which increased during acute HFRS. Maximum NLR levels (NLRmax: median 4.19, range 1.75-13.16) were 2.38-fold higher compared to the reference NLR level of 1.76 in the general population. NLR levels on admission correlate with markers of severity (length of hospital stay, serum creatinine) but not with other markers of severity (leukocytes, platelets, C-reactive protein, lactate dehydrogenase, serum albumin, proteinuria). Interestingly, levels of nephrin, which is a specific marker of podocyte damage in kidney injury, are highest on admission and correlate with NLRmax, but not with NLRadm. Together, we observed a correlation between systemic inflammation and the severity of HFRS, but our results also revealed that podocyte damage precedes these inflammatory processes.

Risk of kidney and liver diseases after COVID-19 infection: A systematic review and meta-analysis

COVID-19 is not only associated with substantial acute liver and kidney injuries, but also with an elevated risk of post-acute sequelae involving the kidney and liver system. We aimed to investigate whether COVID-19 exposure increases the long-term risk of kidney and liver disease, and what are the magnitudes of these associations. We searched PubMed, Embase, Web of Science, ClinicalTrials.gov, and the Living Overview of the Evidence COVID-19 Repository for cohort studies estimating the association between COVID-19 and kidney and liver outcomes. Random-effects meta-analyses were performed to combine the results of the included studies. We assessed the certainty of the evidence using the Grading of Recommendations Assessment, Development and Evaluation approach. Fifteen cohort studies with more than 32 million participants were included in the systematic review COVID-19 was associated with a 35% greater risk of kidney diseases (10 more per 1000 persons; low certainty evidence) and 54% greater risk of liver disease (3 more per 1000 persons; low certainty evidence). The absolute increases due to COVID-19 for acute kidney injury, chronic kidney disease, and liver test abnormality were 3, 8, and 3 per 1000 persons, respectively. Subgroup analyses found no differences between different type of kidney and liver diseases. The findings provide further evidence for the association between COVID-19 and incident kidney and liver conditions. The absolute magnitude of the effect of COVID-19 on kidney and liver outcomes was, however, relatively small.

Association of HIV and viral suppression status with hospital acute kidney injury in the era of antiretroviral therapy

In the modern era, it is unknown if people that are virally suppressed with HIV (PWH) are at increased risk for acute kidney injury (AKI) compared to people without HIV and no studies have compared the risk of AKI by viral suppression status. Here, we determined the associations of HIV status and AKI among PWH with and without viral suppression compared to people without HIV. An observational cohort study of PWH and people without HIV hospitalized in a large New York City health system between 2010-2019 was conducted. Multivariable Cox proportional hazards models were used to determine associations between HIV status and risk of AKI, severe AKI and development of chronic kidney disease (CKD). Among 173,884 hospitalized patients, 4,718 had HIV; 2,532 (53.7%) were virally suppressed and 2,186 (46.3%) were not suppressed. Compared to people without HIV, PWH with and without viral suppression were at increased risk of AKI (adjusted hazard ratio 1.27, 95% confidence interval 1.15, 1.40 and 1.73, 1.58, 1.90, respectively) and AKI requiring kidney replacement therapy (1.89, 1.27, 2.84 and 1.87, 1.23, 2.84, respectively). Incremental, graded associations were observed between HIV status and Stage 2 or 3 AKI, and among AKI survivors, and incident CKD. The elevated risk of AKI across ages of PWH was similar in magnitude to older people without HIV. Thus, regardless of virologic control, HIV is an independent risk factor for AKI among hospitalized patients. Future studies should determine the mechanisms by which HIV increases susceptibility to AKI and identify strategies to prevent AKI in PWH.

Clinical characteristics and factors associated with acute kidney injury among patients hospitalized with coronavirus disease: an observational retrospective study

BACKGROUND

Coronavirus disease 19 (COVID-19) is a multisystemic disease with high incidence of acute kidney injury (AKI).

OBJECTIVE

To describe the clinical characteristics and factors associated with AKI among patients hospitalized with COVID-19.

DESIGN AND SETTING

Retrospective cohort conducted at Hospital Civil de Culiacan, Mexico.

METHODS

We included 307 patients hospitalized due to COVID-19. AKI was defined and staged based on serum creatinine levels in accordance with the criteria of the Acute Kidney Injury Network (AKIN). Multivariate logistic regression analysis was used to determine factors associated with AKI.

RESULTS

The patients' age was 56 ± 15 years (64.5% male). The incidence of AKI was 33.6% (n = 103). Overall, 53.4% of patients had community-acquired AKI, and 46.6% had hospital-acquired AKI. Additionally, 15.5% of them presented AKIN stage 1; 34% had AKIN stage 2; and 50.5% had AKIN stage 3. Hemodialysis was required for 10.7% of the patients. The factors associated with AKI were chronic kidney disease (odds ratio, OR: 10.8; P = 0.04), use of norepinephrine (OR: 7.3; P = 0.002), diabetes mellitus (OR: 2.9; P = 0.03), C-reactive protein level (OR: 1.005; P = 0.01) and COVID-19 severity index based on chest tomography (OR: 1.09; statistical trend, P = 0.07). Hospital stay (11 ± 7 days; P < 0.001) and mortality (83.5 versus 31.4%; P < 0.05) were greater among patients with AKI.

CONCLUSION

AKI was a frequent and serious complication in our cohort of patients hospitalized with COVID-19, which was associated with high mortality and long hospital stay.

Renal replacement therapy for critically ill patients with COVID-19-associated acute kidney injury: A review of current knowledge

The outbreak of coronavirus disease 2019 (COVID-19) has rapidly evolved into a global pandemic. A significant proportion of COVID-19 patients develops severe symptoms, which may include acute respiratory distress syndrome and acute kidney injury as manifestations of multi-organ failure. Acute kidney injury (AKI) necessitating renal replacement therapy (RRT) is increasingly prevalent among critically ill patients with COVID-19. However, few studies have focused on AKI treated with RRT. Many questions are awaiting answers as regards AKI in the setting of COVID-19; whether patients with COVID-19 commonly develop AKI, what are the underlying pathophysiologic mechanisms? What is the best evidence regarding treatment approaches? Identification of the potential indications and the preferred modalities of RRT in this context, is based mainly on clinical experience. Here, we review the current approaches of RRT, required for management of critically ill patients with COVID-19 complicated by severe AKI as well as the precautions that should be adopted by health care providers in dealing with these cases. Electronic search was conducted in MEDLINE, PubMed, ISI Web of Science, and Scopus scientific databases. We searched the terms relevant to this review to identify the relevant studies. We also searched the conference proceedings and ClinicalTrials.gov database.

Latin American registry of renal involvement in COVID-19 disease. The relevance of assessing proteinuria throughout the clinical course

The Latin American Society of Nephrology and Hypertension conducted a prospective cohort, multinational registry of Latin American patients with kidney impairment associated to COVID-19 infection with the objective to describe the characteristics of acute kidney disease under these circumstances. The study was carried out through open invitation in order to describe the characteristics of the disease in the region. Eight-hundred and seventy patients from 12 countries were included. Median age was 63 years (54-74), most of patients were male (68.4%) and with diverse comorbidities (87.2%). Acute kidney injury (AKI) was hospital-acquired in 64.7% and non-oliguric in 59.9%. Multiorgan dysfunction syndrome (MODS) due to COVID-19 and volume depletion were the main factors contributing to AKI (59.2% and 35.7% respectively). Kidney replacement therapy was started in 46.2%. Non-recovery of renal function was observed in 65.3%. 71.5% of patients were admitted to ICU and 72.2% underwent mechanical ventilation. Proteinuria at admission was present in 62.4% of patients and proteinuria during hospital-stay occurred in 37.5%. Those patients with proteinuria at admission had higher burden of comorbidities, higher baseline sCr, and MODS was severe. On the other hand, patients with de novo proteinuria had lower incidence of comorbidities and near normal sCr at admission, but showed adverse course of disease. COVID-19 MODS was the main cause of AKI in both groups. All-cause mortality of the general population was 57.4%, and it was associated to age, sepsis as cause of AKI, severity of condition at admission, oliguria, mechanical ventilation, non-recovery of renal function, in-hospital complications and hospital stay. In conclusion, our study contributes to a better knowledge of this condition and highlights the relevance of the detection of proteinuria throughout the clinical course.

The association of hemoglobin drop with in-hospital outcomes in COVID-19 patients

BACKGROUND

Bleeding events can be critical in hospitalized patients with COVID-19, especially those with aggressive anticoagulation therapy.

AIM

We aimed to investigate whether hemoglobin drop was associated with increased risk of acute kidney injury (AKI) and in-hospital mortality among patients with COVID-19.

DESIGN

Retrospective cohort study.

METHODS

This retrospective study was conducted by review of the medical records of 6683 patients with laboratory-confirmed COVID-19 hospitalized in the Mount Sinai Health system between 1st March 2020 and 30th March 2021. We compared patients with and without hemoglobin drop >3 g/dl during hospitalization within a week after admissions, using inverse probability treatment weighted analysis (IPTW). Outcomes of interest were in-hospital mortality and AKI which was defined as serum creatine change of 0.3 mg/dl increase or 1.5 times baseline.

RESULTS

Of the 6683 patients admitted due to COVID-19, 750 (11.2%) patients presented with a marked hemoglobin drop. Patients with hemoglobin drop were more likely to receive therapeutic anticoagulation within 2 days after admissions. Patients with hemoglobin drop had higher crude in-hospital mortality (40.8% vs. 20.0%, P < 0.001) as well as AKI (51.4% vs. 23.9%, P < 0.001) compared to those without. IPTW analysis showed that hemoglobin drop was associated with higher in-hospital mortality compared to those without (odds ratio (OR) [95% confidential interval (CI)]: 2.21 [1.54-2.88], P < 0.001) as well as AKI (OR [95% CI]: 2.79 [2.08-3.73], P < 0.001).

CONCLUSIONS

Hemoglobin drop during COVID-19 related hospitalizations was associated with a higher risk of AKI and in-hospital mortality.

A 67-Year-Old Male Patient With COVID-19 With Worsening Respiratory Function and Acute Kidney Failure

CASE PRESENTATION

A 67-year-old obese man (BMI 38.0) with type 2 diabetes mellitus (DM), chronic atrial fibrillation, and chronic lymphocytic leukemia stage II, stable for 8 years after chemotherapy, and a history of smoking presented to the ED with progressive dyspnea and fever due to SARS-CoV-2 infection. He was admitted to a general ward and treated with dexamethasone (6 mg IV once daily) and oxygen. On day 3 of hospital admission, he became progressively hypoxemic and was admitted to the ICU for invasive mechanical ventilation. Dexamethasone treatment was continued, and a single dose of tocilizumab (800 mg) was administered. On day 9 of ICU admission, voriconazole treatment was initiated after tracheal white plaques at bronchoscopy, suggestive of invasive Aspergillus tracheobronchitis, were noticed. However, his medical situation dramatically deteriorated.

Clinical profile and outcomes of COVID-19 patients with acute kidney injury: a tertiary centre experience from South India

AIM

The rates of development of acute kidney injury (AKI) in COVID-19 have been variably reported from across the world. Prevalence and outcomes of AKI in hospitalised COVID-19 patients in India has not been studied well.

METHODS

This was a retrospective observational study amongst adult hospitalised COVID-19 patients admitted at a tertiary care centre between May 1 and October 31, 2020. We estimated the prevalence of AKI and outcomes including mortality and acute kidney disease (AKD) at the time of discharge. Regression analysis was done to study the factors associated with mortality and AKD.

RESULTS

Out of 2650 hospitalised patients with COVID-19, 190 (7.2%) patients developed AKI. Mean age of patients with AKI was 62.6 years, 81.6% were male. Comorbidities included diabetes mellitus in 72.1%, hypertension in 66.8%, heart disease in 30% and chronic kidney disease (CKD) in 22.6%. Most patients had stage 1 AKI (71.1%). Overall mortality in patients with AKI was 22.1%, 75% in those requiring dialysis and 74.5% in those requiring ICU. Amongst survivors without pre-existing CKD, 40.9% patients had acute kidney disease at the time of discharge. Higher age, stage 3 AKI and need for mechanical ventilation were associated with higher mortality. On multivariable regression, factors associated with AKD at discharge included pre-existing heart disease and severe albuminuria during hospitalisation.

CONCLUSION

In our study population, we found a low prevalence of AKI. Mortality was high in AKI patients requiring ICU care and dialysis. Amongst survivors, a significant percentage had AKD at the time of discharge.

SARS-CoV-2 N Protein Induces Acute Kidney Injury via Smad3-Dependent G1 Cell Cycle Arrest Mechanism

COVID-19 is infected by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and can cause severe multiple organ injury and death. Kidney is one of major target organs of COVID-19 and acute kidney injury (AKI) is common in critically ill COVID-19 patients. However, mechanisms through which COVID-19 causes AKI remain largely unknown and treatment remains unspecific and ineffective. Here, the authors report that normal kidney-specifically overexpressing SARS-CoV-2 N develops AKI, which worsens in mice under ischemic condition. Mechanistically, it is uncovered that SARS-CoV-2 N-induced AKI is Smad3-dependent as SARS-CoV-2 N protein can interact with Smad3 and enhance TGF-β/Smad3 signaling to cause tubular epithelial cell death and AKI via the G1 cell cycle arrest mechanism. This is further confirmed in Smad3 knockout mice and cells in which deletion of Smad3 protects against SARS-CoV-2 N protein-induced cell death and AKI in vivo and in vitro. Most significantly, it is also found that targeting Smad3 with a Smad3 pharmacological inhibitor is able to inhibit SARS-CoV-2 N-induced AKI. In conclusion, the authors identify that SARS-CoV-2 N protein is a key mediator for AKI and induces AKI via the Smad3-dependent G1 cell cycle arrest mechanism. Targeting Smad3 may represent as a novel therapy for COVID-19-asscoaited AKI.

Sex-related differences in mortality, acute kidney injury, and respiratory failure among critically ill patients with COVID-19

Although the number of deaths due to coronavirus disease 2019 (COVID-19) is higher in men than women, prior studies have provided limited sex-stratified clinical data.We evaluated sex-related differences in clinical outcomes among critically ill adults with COVID-19.Multicenter cohort study of adults with laboratory-confirmed COVID-19 admitted to intensive care units at 67 U.S. hospitals from March 4 to May 9, 2020. Multilevel logistic regression was used to evaluate 28-day in-hospital mortality, severe acute kidney injury (AKI requiring kidney replacement therapy), and respiratory failure occurring within 14 days of intensive care unit admission.A total of 4407 patients were included (median age, 62 years; 2793 [63.4%] men; 1159 [26.3%] non-Hispanic White; 1220 [27.7%] non-Hispanic Black; 994 [22.6%] Hispanic). Compared with women, men were younger (median age, 61 vs 64 years, less likely to be non-Hispanic Black (684 [24.5%] vs 536 [33.2%]), and more likely to smoke (877 [31.4%] vs 422 [26.2%]). During median follow-up of 14 days, 1072 men (38.4%) and 553 women (34.3%) died. Severe AKI occurred in 590 men (21.8%), and 239 women (15.5%), while respiratory failure occurred in 2255 men (80.7%) and 1234 women (76.5%). After adjusting for age, race/ethnicity and clinical variables, compared with women, men had a higher risk of death (OR, 1.50, 95% CI, 1.26-1.77), severe AKI (OR, 1.92; 95% CI 1.57-2.36), and respiratory failure (OR, 1.42; 95% CI, 1.11-1.80).In this multicenter cohort of critically ill adults with COVID-19, men were more likely to have adverse outcomes compared with women.

Outcomes of critically ill patients with acute kidney injury in COVID-19 infection: an observational study

BACKGROUND

Early reports indicate that AKI is common during COVID-19 infection. Different mortality rates of AKI due to SARS-CoV-2 have been reported, based on the degree of organic dysfunction and varying from public to private hospitals. However, there is a lack of data about AKI among critically ill patients with COVID-19.

METHODS

We conducted a multicenter cohort study of 424 critically ill adults with severe acute respiratory syndrome (SARS) and AKI, both associated with SARS-CoV-2, admitted to six public ICUs in Brazil. We used multivariable logistic regression to identify risk factors for AKI severity and in-hospital mortality.

RESULTS

The average age was 66.42 ± 13.79 years, 90.3% were on mechanical ventilation (MV), 76.6% were at KDIGO stage 3, and 79% underwent hemodialysis. The overall mortality was 90.1%. We found a higher frequency of dialysis (82.7% versus 45.2%), MV (95% versus 47.6%), vasopressors (81.2% versus 35.7%) (p < 0.001) and severe AKI (79.3% versus 52.4%; p = 0.002) in nonsurvivors. MV, vasopressors, dialysis, sepsis-associated AKI, and death (p < 0.001) were more frequent in KDIGO 3. Logistic regression for death demonstrated an association with MV (OR = 8.44; CI 3.43-20.74) and vasopressors (OR = 2.93; CI 1.28-6.71; p < 0.001). Severe AKI and dialysis need were not independent risk factors for death. MV (OR = 2.60; CI 1.23-5.45) and vasopressors (OR = 1.95; CI 1.12-3.99) were also independent risk factors for KDIGO 3 (p < 0.001).

CONCLUSION

Critically ill patients with SARS and AKI due to COVID-19 had high mortality in this cohort. Mortality was largely determined by the need for mechanical ventilation and vasopressors rather than AKI severity.

[PEDIATRIC NEPHROLOGY IN THE TIME OF CORONA]

Symptomatic coronavirus 2019 (COVID-19) infection usually presents with upper airway symptoms, but may lead to complications, such as pneumonia and involvement of other organs, or even death. Children often have a mild clinical course or may be asymptomatic, however, a severe complication of multisystem inflammatory syndrome has been described in rare cases. In severe COVID-19 infection, acute kidney injury may manifest even in children without comorbidities. The aim of this review is to present available data on renal involvement in pediatric COVID-19, and disease manifestations in children with underlying chronic kidney disease (CKD) or children receiving immunosuppressive medications due to kidney transplantation or glomerular disease. Although it could be assumed that children with CKD, including immunosuppressed patients, might be a high risk group for infection and severity of COVID-19 disease, this is not supported by current available data.

Pathophysiology of COVID-19-associated acute kidney injury

Although respiratory failure and hypoxaemia are the main manifestations of COVID-19, kidney involvement is also common. Available evidence supports a number of potential pathophysiological pathways through which acute kidney injury (AKI) can develop in the context of SARS-CoV-2 infection. Histopathological findings have highlighted both similarities and differences between AKI in patients with COVID-19 and in those with AKI in non-COVID-related sepsis. Acute tubular injury is common, although it is often mild, despite markedly reduced kidney function. Systemic haemodynamic instability very likely contributes to tubular injury. Despite descriptions of COVID-19 as a cytokine storm syndrome, levels of circulating cytokines are often lower in patients with COVID-19 than in patients with acute respiratory distress syndrome with causes other than COVID-19. Tissue inflammation and local immune cell infiltration have been repeatedly observed and might have a critical role in kidney injury, as might endothelial injury and microvascular thrombi. Findings of high viral load in patients who have died with AKI suggest a contribution of viral invasion in the kidneys, although the issue of renal tropism remains controversial. An impaired type I interferon response has also been reported in patients with severe COVID-19. In light of these observations, the potential pathophysiological mechanisms of COVID-19-associated AKI may provide insights into therapeutic strategies.

Abnormal Blood Coagulation and Kidney Damage in Aged Hamsters Infected with Severe Acute Respiratory Syndrome Coronavirus 2

Systemic symptoms have often been observed in patients with coronavirus disease 2019 (COVID-19) in addition to pneumonia, however, the details are still unclear due to the lack of an appropriate animal model. In this study, we investigated and compared blood coagulation abnormalities and tissue damage between male Syrian hamsters of 9 (young) and over 36 (aged) weeks old after intranasal infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Despite similar levels of viral replication and inflammatory responses in the lungs of both age groups, aged but not young hamsters showed significant prolongation of prothrombin time and prominent acute kidney damage. Moreover, aged hamsters demonstrated increased intravascular coagulation time-dependently in the lungs, suggesting that consumption of coagulation factors causes prothrombin time prolongation. Furthermore, proximal urinary tract damage and mesangial matrix expansion were observed in the kidneys of the aged hamsters at early and later disease stages, respectively. Given that the severity and mortality of COVID-19 are higher in elderly human patients, the effect of aging on pathogenesis needs to be understood and should be considered for the selection of animal models. We, thus, propose that the aged hamster is a good small animal model for COVID-19 research.

Association of Inflammatory Biomarkers with Immunosuppression Management and Outcomes in Kidney Transplant Recipients with COVID-19

BACKGROUND

Kidney transplant recipients with coronavirus disease 2019 (COVID-19) are at increased risk for adverse outcomes, such as acute kidney injury (AKI), intensive care unit (ICU) admission, and death. The association of inflammatory biomarkers with outcomes and the impact of changes in immunosuppression on biomarker levels are unknown.

METHODS

We investigated factors associated with a composite of AKI, ICU admission, or death, and whether immunosuppression changes correlated with changes in inflammatory biomarkers and outcomes in kidney transplant recipients with a positive severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) polymerase chain reaction.

RESULTS

Of 59 patients, 50% had estimated glomerular filtration rate (eGFR) <60 mL/min/1.73 m2. Patients who discontinued calcineurin inhibitors (CNIs) had higher peak high-sensitivity C-reactive protein (hs-CRP) than those who maintained the same dose (median, 344; interquartile range [IQR], 145-374 vs median, 41; IQR, 22-116 mg/L, P = .03). Of the patients, 73% were hospitalized, 22% had admissions to the ICU, and 20% died. Of the 56% with AKI, 35% required dialysis. All patients with AKI but without pulmonary manifestations recovered to 10% of baseline creatinine levels. Factors associated with the composite outcome were eGFR <60 mL/min/1.73 m2 (odds ratio [OR], 5.833; 95% confidence interval [CI], 1.880-18.099; P = .002), hs-CRP (OR, 1.011/unit increase; 95% CI, 1.002-1.021; P = .019), white blood cell count (OR, 1.173/unit increase; 95% CI, 1.006-1.368; P = .041), and decreased or discontinued CNI (OR, 4.286; 95% CI, 1.353-13.572; P = .013). eGFR<60 mL/min/1.73 m2 (OR, 11.176; 95% CI, 1.581-79.001; P = .016), and peak hs-CRP (OR, 1.010/unit increase; 95% CI, 1.000-1.020; P = .049) remained associated with the composite in the multivariable model.

CONCLUSIONS

Kidney transplant recipients with COVID-19 have high rates of ICU admissions, AKI, and death. Those with eGFR<60 mL/min/1.73 m2 are at highest risk. CNI reduction is associated with higher inflammatory biomarkers, correlating with worse outcomes. More studies are needed to determine if this association should drive clinical management.